Journal articles: 'Golgo 13'

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Casey, Carol, Paul Thomes, Sonia Manca, and Armen Petrosyan. "Giantin Is Required for Post-Alcohol Recovery of Golgi in Liver Cells." Biomolecules 8, no. 4 (November 16, 2018): 150. http://dx.doi.org/10.3390/biom8040150.

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In hepatocytes and alcohol-metabolizing cultured cells, Golgi undergoes ethanol (EtOH)-induced disorganization. Perinuclear and organized Golgi is important in liver homeostasis, but how the Golgi remains intact is unknown. Work from our laboratories showed that EtOH-altered cellular function could be reversed after alcohol removal; we wanted to determine whether this recovery would apply to Golgi. We used alcohol-metabolizing HepG2 (VA-13) cells (cultured with or without EtOH for 72 h) and rat hepatocytes (control and EtOH-fed (Lieber–DeCarli diet)). For recovery, EtOH was removed and replenished with control medium (48 h for VA-13 cells) or control diet (10 days for rats). Results: EtOH-induced Golgi disassembly was associated with de-dimerization of the largest Golgi matrix protein giantin, along with impaired transport of selected hepatic proteins. After recovery from EtOH, Golgi regained their compact structure, and alterations in giantin and protein transport were restored. In VA-13 cells, when we knocked down giantin, Rab6a GTPase or non-muscle myosin IIB, minimal changes were observed in control conditions, but post-EtOH recovery was impaired. Conclusions: These data provide a link between Golgi organization and plasma membrane protein expression and identify several proteins whose expression is important to maintain Golgi structure during the recovery phase after EtOH administration.

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Loizaga de Castro, Rocío, Fabiana Saporiti, Damián G. Vales, Néstor A. García, Luis Cardona, and Enrique A. Crespo. "Feeding ecology of dusky dolphins Lagenorhynchus obscurus : evidence from stable isotopes." Journal of Mammalogy 97, no. 1 (November 9, 2015): 310–20. http://dx.doi.org/10.1093/jmammal/gyv180.

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Abstract The dusky dolphin Lagenorhynchus obscurus occurs in the Southern Hemisphere, where it is restricted to coastal temperate areas. This study aimed to characterize the feeding ecology of dusky dolphins inhabiting northern and central Patagonia by using δ 13 C and δ 15 N stable isotope ratios in skin samples. We searched for evidence of geographical and seasonal variation in diet and we explored dietary differences between sexes. Significant differences in the stable isotope ratios of dusky dolphins were found among the 4 gulfs under study. Skin samples from Golfo San Matías and Golfo San Jorge were 13 C-enriched and 15 N-depleted compared to those from Golfo Nuevo and Golfo San José. There was no seasonality in the diet at Golfo Nuevo, and no differences in the diet between sexes in any gulf. Furthermore, Bayesian ellipses of males and females were similar in size and the overlap was mostly symmetrical in Golfo San José and Golfo San Jorge, while in the Golfo San Matías and Golfo Nuevo, females had wider ranges of δ 15 N, suggesting the exploitation of a wider trophic niche. Finally, pelagic fishes and demersal pelagic squids were identified as the main prey for this species of dolphin, although the proportion of each prey varied regionally. El delfín oscuro Lagenorhynchus obscurus se distribuye ampliamente en el Hemisferio Sur, donde prefiere áreas templadas costeras. Este estudio tuvo como objetivo caracterizar la ecología trófica de delfines oscuros que habitan en el norte y centro de la Patagonia mediante el uso de isótopos estables de δ 13 C y δ 15 N en muestras de piel. Específicamente, buscamos evidencia de variación geográfica y estacional en la dieta de los delfines y exploramos la diferencia de dieta entre sexos. Se encontraron diferencias significativas en los valores de isótopos estables de los delfines entre los cuatro golfos bajo estudio. Las muestras de piel de Golfo San Matías y Golfo San Jorge se encuentran enriquecidas en 13 C y deprimidas en 15 N en comparación con las muestras del Golfo Nuevo y Golfo San José. No hubo estacionalidad en la dieta en el Golfo Nuevo, y no hay diferencias en la dieta entre sexos en ningún golfo. Además, las elipses bayesianas de machos y hembras fueron similares en tamaño y la superposición fue mayormente simétrica en el Golfo San José y el Golfo San Jorge, mientras que en el Golfo San Matías y el Golfo Nuevo, las hembras tienen rangos más amplios de δ 15 N, lo que sugiere la explotación de un nicho trófico más amplio. Por último, los peces pelágicos y los calamares demersales pelágicos fueron identificados como la presa principal de esta especie de delfín, aunque la contribución de cada presa varió regionalmente.

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Zhou, Z., M. M. Mogensen, P. P. Powell, S. Curry, and T. Wileman. "Foot-and-Mouth Disease Virus 3C Protease Induces Fragmentation of the Golgi Compartment and Blocks Intra-Golgi Transport." Journal of Virology 87, no. 21 (August 28, 2013): 11721–29. http://dx.doi.org/10.1128/jvi.01355-13.

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Sengupta, Prabuddha, Prasanna Satpute-Krishnan, Arnold Y. Seo, Dylan T. Burnette, George H. Patterson, and Jennifer Lippincott-Schwartz. "ER trapping reveals Golgi enzymes continually revisit the ER through a recycling pathway that controls Golgi organization." Proceedings of the National Academy of Sciences 112, no. 49 (November 23, 2015): E6752—E6761. http://dx.doi.org/10.1073/pnas.1520957112.

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Whether Golgi enzymes remain localized within the Golgi or constitutively cycle through the endoplasmic reticulum (ER) is unclear, yet is important for understanding Golgi dependence on the ER. Here, we demonstrate that the previously reported inefficient ER trapping of Golgi enzymes in a rapamycin-based assay results from an artifact involving an endogenous ER-localized 13-kD FK506 binding protein (FKBP13) competing with the FKBP12-tagged Golgi enzyme for binding to an FKBP-rapamycin binding domain (FRB)-tagged ER trap. When we express an FKBP12-tagged ER trap and FRB-tagged Golgi enzymes, conditions precluding such competition, the Golgi enzymes completely redistribute to the ER upon rapamycin treatment. A photoactivatable FRB-Golgi enzyme, highlighted only in the Golgi, likewise redistributes to the ER. These data establish Golgi enzymes constitutively cycle through the ER. Using our trapping scheme, we identify roles of rab6a and calcium-independent phospholipase A2 (iPLA2) in Golgi enzyme recycling, and show that retrograde transport of Golgi membrane underlies Golgi dispersal during microtubule depolymerization and mitosis.

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Jin, Di, Jun Tao, Dan Li, Yanan Wang, Li Li, Zhongdong Hu, Zhenzhen Zhou, Xiuli Chang, Chunfeng Qu, and Hongbing Zhang. "Golgi protein 73 activation of MMP-13 promotes hepatocellular carcinoma cell invasion." Oncotarget 6, no. 32 (September 10, 2015): 33523–33. http://dx.doi.org/10.18632/oncotarget.5590.

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Chao, Daniel S., Jesse C. Hay, Shawn Winnick, Rytis Prekeris, Judith Klumperman, and Richard H. Scheller. "SNARE Membrane Trafficking Dynamics In Vivo." Journal of Cell Biology 144, no. 5 (March 8, 1999): 869–81. http://dx.doi.org/10.1083/jcb.144.5.869.

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The ER/Golgi soluble NSF attachment protein receptor (SNARE) membrin, rsec22b, and rbet1 are enriched in ∼1-μm cytoplasmic structures that lie very close to the ER. These appear to be ER exit sites since secretory cargo concentrates in and exits from these structures. rsec22b and rbet1 fused to fluorescent proteins are enriched at ∼1-μm ER exit sites that remained more or less stationary, but periodically emitted streaks of fluorescence that traveled generally in the direction of the Golgi complex. These exit sites were reused and subsequent tubules or streams of vesicles followed similar trajectories. Fluorescent membrin- enriched ∼1-μm peripheral structures were more mobile and appeared to translocate through the cytoplasm back and forth, between the periphery and the Golgi area. These mobile structures could serve to collect secretory cargo by fusing with ER-derived vesicles and ferrying the cargo to the Golgi. The post-Golgi SNAREs, syntaxin 6 and syntaxin 13, when fused to fluorescent proteins each displayed characteristic patterns of movement. However, syntaxin 13 was the only SNARE whose life cycle appeared to involve interactions with the plasma membrane. These studies reveal the in vivo spatiotemporal dynamics of SNARE proteins and provide new insight into their roles in membrane trafficking.

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Corse, Emily, and Carolyn E. Machamer. "The Cytoplasmic Tail of Infectious Bronchitis Virus E Protein Directs Golgi Targeting." Journal of Virology 76, no. 3 (February 1, 2002): 1273–84. http://dx.doi.org/10.1128/jvi.76.3.1273-1284.2002.

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ABSTRACT We have previously shown that the E protein of the coronavirus infectious bronchitis virus (IBV) is localized to the Golgi complex when expressed exogenously from cDNA. Here, we report that neither the transmembrane domain nor the short lumenal domain of IBV E is required for Golgi targeting. However, an N-terminal truncation containing only the cytoplasmic domain (CTE) was efficiently localized to the Golgi complex, and this domain could retain a reporter protein in the Golgi. Thus, the cytoplasmic tail of the E protein is necessary and sufficient for Golgi targeting. The IBV E protein is palmitoylated on one or two cysteine residues adjacent to its transmembrane domain, but palmitoylation was not required for proper Golgi targeting. Using C-terminal truncations, we determined that the IBV E Golgi targeting information is present between tail amino acids 13 and 63. Upon treatment with brefeldin A, both the E and CTE proteins redistributed to punctate structures that colocalized with the Golgi matrix proteins GM130 and p115 instead of being localized to the endoplasmic reticulum like Golgi glycosylation enzymes. This suggests that IBV E is associated with the Golgi matrix through interactions of its cytoplasmic tail and may have interesting implications for coronavirus assembly in early Golgi compartments.

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WESTERMANN, Peter, Maria KNOBLICH, Olaf MAIER, Carsten LINDSCHAU, and Hermann HALLER. "Protein kinase C bound to the Golgi apparatus supports the formation of constitutive transport vesicles." Biochemical Journal 320, no. 2 (December 1, 1996): 651–58. http://dx.doi.org/10.1042/bj3200651.

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Constitutive secretion of heparan sulphate proteoglycans (HSPGs) was stimulated in human hepatoma HepG2 cells by phorbol 12-myristate 13-acetate (PMA) and inhibited by calphostin C, a specific inhibitor of protein kinase C (PKC). To delineate more closely the site of PKC action, the packaging in vitro of 35SO4-labelled HSPGs into transport vesicles was investigated. Formation of transport vesicles at the trans-Golgi network was stimulated by PMA and inhibited by calphostin C or Ro 31-8220 by using a post-nuclear supernatant. Treatment of either isolated Golgi-enriched membranes or cytosolic proteins with calphostin C provided evidence that membrane-bound PKC forms strongly supported vesicle formation, whereas cytosolic PKC forms showed a marginal effect. The PKC isoforms PKC-α and PKC-ζ were attached to highly purified Golgi membranes, as shown by Western blotting. Both isoforms were localized by confocal immunofluorescence microscopy in the Golgi area of HepG2 cells. Immunoelectron microscopy of ultrathin cryosections of HepG2 cells showed that PKC-ζ predominantly attaches to the trans-Golgi region, whereas PKC-α binds to the cis- and trans-Golgi area.

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9

Tantra, M., L. Guo, J. Kim, N. Zainolabidin, V. Eulenburg, G. J. Augustine, and A. I. Chen. "Conditional deletion of Cadherin 13 perturbs Golgi cells and disrupts social and cognitive behaviors." Genes, Brain and Behavior 17, no. 6 (March 15, 2018): e12466. http://dx.doi.org/10.1111/gbb.12466.

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Johnston, P. A., A. Stieber, and N. K. Gonatas. "A hypothesis on the traffic of MG160, a medial Golgi sialoglycoprotein, from the trans-Golgi network to the Golgi cisternae." Journal of Cell Science 107, no. 3 (March 1, 1994): 529–37. http://dx.doi.org/10.1242/jcs.107.3.529.

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We have reported that MG160, an intrinsic membrane sialoglycoprotein of the Golgi apparatus (GA), resides in the medial cisternae of the organelle (Gonatas et al. (1989) J. Biol. Chem. 264, 646–653). In order to resolve the question whether MG160 acquires sialic acid residues in the trans cisternae or trans-Golgi network (TGN) prior to its retrograde transport, we have examined the effects of brefeldin A (BFA) on the post-translational processing of MG160, and the distribution of internalized wheat germ agglutinin covalently linked with HRP (WGA-HRP), which labels the TGN (Gonatas et al. (1977) J. Cell Biol. 73, 1–13). In BFA-treated PC12 cells, MG160 acquires resistance to endo H, but fails to be sialylated. This effect occurs in parallel with the redistribution of MG160 into an ER compartment dispersed throughout the cytoplasm including the nuclear envelope, and the collapse of the WGA-HRP-labelled TGN into vesicles and tubules surrounding the centriole. These results suggest that MG160 is not sialylated in BFA-treated cells because it is sequestered from the sialyltransferase enzyme(s), presumably located in the TGN, and provide evidence supporting the hypothesis for a retrograde transport pathway that recycles resident GA proteins, including MG160, between the Golgi cisternae and the TGN. To examine further the above hypothesis we studied cells treated with BFA and then allowed to recover from the effect of the drug for various lengths of time. After 15 minutes of recovery, cisternae of the Golgi apparatus, typically found in the pericentriolar region, are labeled by both MG160 and WGA-HRP.(ABSTRACT TRUNCATED AT 250 WORDS)

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Chen, Ji-Long, Raymond V. Fucini, Lynne Lacomis, Hediye Erdjument-Bromage, Paul Tempst, and Mark Stamnes. "Coatomer-bound Cdc42 regulates dynein recruitment to COPI vesicles." Journal of Cell Biology 169, no. 3 (May 2, 2005): 383–89. http://dx.doi.org/10.1083/jcb.200501157.

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Cytoskeletal dynamics at the Golgi apparatus are regulated in part through a binding interaction between the Golgi-vesicle coat protein, coatomer, and the regulatory GTP-binding protein Cdc42 (Wu, W.J., J.W. Erickson, R. Lin, and R.A. Cerione. 2000. Nature. 405:800–804; Fucini, R.V., J.L. Chen, C. Sharma, M.M. Kessels, and M. Stamnes. 2002. Mol. Biol. Cell. 13:621–631). The precise role of this complex has not been determined. We have analyzed the protein composition of Golgi-derived coat protomer I (COPI)–coated vesicles after activating or inhibiting signaling through coatomer-bound Cdc42. We show that Cdc42 has profound effects on the recruitment of dynein to COPI vesicles. Cdc42, when bound to coatomer, inhibits dynein binding to COPI vesicles whereas preventing the coatomer–Cdc42 interaction stimulates dynein binding. Dynein recruitment was found to involve actin dynamics and dynactin. Reclustering of nocodazole-dispersed Golgi stacks and microtubule/dynein-dependent ER-to-Golgi transport are both sensitive to disrupting Cdc42 mediated signaling. By contrast, dynein-independent transport to the Golgi complex is insensitive to mutant Cdc42. We propose a model for how proper temporal regulation of motor-based vesicle translocation could be coupled to the completion of vesicle formation.

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Chen, Esther J., Alison R. Frand, Elizabeth Chitouras, and Chris A. Kaiser. "A Link between Secretion and Pre-mRNA Processing Defects in Saccharomyces cerevisiae and the Identification of a Novel Splicing Gene, RSE1." Molecular and Cellular Biology 18, no. 12 (December 1, 1998): 7139–46. http://dx.doi.org/10.1128/mcb.18.12.7139.

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ABSTRACT Secretory proteins in eukaryotic cells are transported to the cell surface via the endoplasmic reticulum (ER) and the Golgi apparatus by membrane-bounded vesicles. We screened a collection of temperature-sensitive mutants of Saccharomyces cerevisiaefor defects in ER-to-Golgi transport. Two of the genes identified in this screen were PRP2, which encodes a known pre-mRNA splicing factor, and RSE1, a novel gene that we show to be important for pre-mRNA splicing. Both prp2-13 andrse1-1 mutants accumulate the ER forms of invertase and the vacuolar protease CPY at restrictive temperature. The secretion defect in each mutant can be suppressed by increasing the amount ofSAR1, which encodes a small GTPase essential for COPII vesicle formation from the ER, or by deleting the intron from theSAR1 gene. These data indicate that a failure to spliceSAR1 pre-mRNA is the specific cause of the secretion defects in prp2-13 and rse1-1. Moreover, these data imply that Sar1p is a limiting component of the ER-to-Golgi transport machinery and suggest a way that secretory pathway function might be coordinated with the amount of gene expression in a cell.

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Teoule, F., C. Brisac, I. Pelletier, P. O. Vidalain, S. Jegouic, C. Mirabelli, M. Bessaud, et al. "The Golgi Protein ACBD3, an Interactor for Poliovirus Protein 3A, Modulates Poliovirus Replication." Journal of Virology 87, no. 20 (August 7, 2013): 11031–46. http://dx.doi.org/10.1128/jvi.00304-13.

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Kabeiseman, Emily J., Kyle Cichos, Ted Hackstadt, Andrea Lucas, and Elizabeth R. Moore. "Vesicle-Associated Membrane Protein 4 and Syntaxin 6 Interactions at the Chlamydial Inclusion." Infection and Immunity 81, no. 9 (June 24, 2013): 3326–37. http://dx.doi.org/10.1128/iai.00584-13.

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ABSTRACTThe predominant players in membrane fusion events are thesolubleN-ethylmaleimide-sensitive factorattachment proteinreceptor (SNARE) family of proteins. We hypothesize that SNARE proteins mediate fusion events at the chlamydial inclusion and are important for chlamydial lipid acquisition. We have previously demonstrated thattrans-Golgi SNARE syntaxin 6 localizes to the chlamydial inclusion. To investigate the role of syntaxin 6 at the chlamydial inclusion, we examined the localization and function of anothertrans-Golgi SNARE and syntaxin 6-binding partner, vesicle-associated membrane protein 4 (VAMP4), at the chlamydial inclusion. In this study, we demonstrate that syntaxin 6 and VAMP4 colocalize to the chlamydial inclusion and interact at the chlamydial inclusion. Furthermore, in the absence of VAMP4, syntaxin 6 is not retained at the chlamydial inclusion. Small interfering RNA (siRNA) knockdown of VAMP4 inhibited chlamydial sphingomyelin acquisition, correlating with a log decrease in infectious progeny. VAMP4 retention at the inclusion was shown to be dependent onde novochlamydial protein synthesis, but unlike syntaxin 6, VAMP4 recruitment is observed in a species-dependent manner. Notably, VAMP4 knockdown inhibits sphingomyelin trafficking only to inclusions in which it localizes. These data support the hypothesis that VAMP proteins play a central role in mediating eukaryotic vesicular interactions at the chlamydial inclusion and, thus, support chlamydial lipid acquisition and chlamydial development.

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Schaub, Beat E., Bea Berger, Eric G. Berger, and Jack Rohrer. "Transition of Galactosyltransferase 1 from Trans-Golgi Cisterna to the Trans-Golgi Network Is Signal Mediated." Molecular Biology of the Cell 17, no. 12 (December 2006): 5153–62. http://dx.doi.org/10.1091/mbc.e06-08-0665.

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The Golgi apparatus (GA) is the organelle where complex glycan formation takes place. In addition, it is a major sorting site for proteins destined for various subcellular compartments or for secretion. Here we investigate β1,4-galactosyltransferase 1 (galT) and α2,6-sialyltransferase 1 (siaT), two trans-Golgi glycosyltransferases, with respect to their different pathways in monensin-treated cells. Upon addition of monensin galT dissociates from siaT and the GA and accumulates in swollen vesicles derived from the trans-Golgi network (TGN), as shown by colocalization with TGN46, a specific TGN marker. We analyzed various chimeric constructs of galT and siaT by confocal fluorescence microscopy and time-lapse videomicroscopy as well as Optiprep density gradient fractionation. We show that the first 13 amino acids of the cytoplasmic tail of galT are necessary for its localization to swollen vesicles induced by monensin. We also show that the monensin sensitivity resulting from the cytoplasmic tail can be conferred to siaT, which leads to the rapid accumulation of the galT–siaT chimera in swollen vesicles upon monensin treatment. On the basis of these data, we suggest that cycling between the trans-Golgi cisterna and the trans-Golgi network of galT is signal mediated.

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Wilkinson, J., J. A. Higgins, P. H. E. Groot, E. Gherardi, and D. E. Bowyer. "Determination of the intracellular distribution and pool sizes of apolipoprotein B in rabbit liver." Biochemical Journal 288, no. 2 (December 1, 1992): 413–19. http://dx.doi.org/10.1042/bj2880413.

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We have investigated the intracellular distribution of apolipoprotein B (apo B) in rabbit liver by immunoblotting, radioimmunoassay (r.i.a.) and enzyme-linked immunoassay (e.l.i.s.a.). Apo B100 was detected in total microsomes, rough microsomes, smooth microsomes, trans-enriched Golgi and cis-enriched Golgi and membrane and cisternal-content subfractions prepared from these fractions. There was also evidence of degradation of apo B100 in the Golgi membrane fractions. The amount of apo B in the subcellular fractions detected by competitive r.i.a. or e.l.i.s.a. ranged from 1.5 micrograms/mg of protein in the rough endoplasmic reticulum to 13 micrograms/mg of protein in the trans-Golgi fraction. Using internal standards (NADPH-cytochrome c reductase for the endoplasmic reticulum and galactosyltransferase for the Golgi membranes) it was calculated that all the apo B of liver is recovered within the secretory compartment, with 63% of the total apo B in the endoplasmic reticulum and the remainder in the Golgi. When the subcellular fractions were separated into membranes and cisternal contents, 60%, 50%, 60% and 30% of the total apo B was recovered in the membrane of the rough microsomes, smooth microsomes, cis-Golgi and trans-Golgi respectively. Using competitive e.l.i.s.a. we found that the membrane-bound form of the apo B was exposed at the cytosolic surface of the intact subcellular fractions. These observations are consistent with a model for assembly of very-low-density lipoproteins (VLDL) in which newly synthesized apo B is incorporated into a membrane-bound pool and a lumenal pool. The membrane-bound pool not used for VLDL assembly may be degraded, possibly in the Golgi region.

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Dahm, Thorsten, Jamie White, Stephan Grill, Joachim Füllekrug, and Ernst H. K. Stelzer. "Quantitative ER ↔ Golgi Transport Kinetics and Protein Separation upon Golgi Exit Revealed by Vesicular Integral Membrane Protein 36 Dynamics in Live Cells." Molecular Biology of the Cell 12, no. 5 (May 2001): 1481–98. http://dx.doi.org/10.1091/mbc.12.5.1481.

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To quantitatively investigate the trafficking of the transmembrane lectin VIP36 and its relation to cargo-containing transport carriers (TCs), we analyzed a C-terminal fluorescent-protein (FP) fusion, VIP36-SP-FP. When expressed at moderate levels, VIP36-SP-FP localized to the endoplasmic reticulum, Golgi apparatus, and intermediate transport structures, and colocalized with epitope-tagged VIP36. Temperature shift and pharmacological experiments indicated VIP36-SP-FP recycled in the early secretory pathway, exhibiting trafficking representative of a class of transmembrane cargo receptors, including the closely related lectin ERGIC53. VIP36-SP-FP trafficking structures comprised tubules and globular elements, which translocated in a saltatory manner. Simultaneous visualization of anterograde secretory cargo and VIP36-SP-FP indicated that the globular structures were pre-Golgi carriers, and that VIP36-SP-FP segregated from cargo within the Golgi and was not included in post-Golgi TCs. Organelle-specific bleach experiments directly measured the exchange of VIP36-SP-FP between the Golgi and endoplasmic reticulum (ER). Fitting a two-compartment model to the recovery data predicted first order rate constants of 1.22 ± 0.44%/min for ER → Golgi, and 7.68 ± 1.94%/min for Golgi → ER transport, revealing a half-time of 113 ± 70 min for leaving the ER and 1.67 ± 0.45 min for leaving the Golgi, and accounting for the measured steady-state distribution of VIP36-SP-FP (13% Golgi/87% ER). Perturbing transport with AlF4−treatment altered VIP36-SP-GFP distribution and changed the rate constants. The parameters of the model suggest that relatively small differences in the first order rate constants, perhaps manifested in subtle differences in the tendency to enter distinct TCs, result in large differences in the steady-state localization of secretory components.

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Snoek, G. T., J. Westerman, F. S. Wouters, and K. W. A. Wirtz. "Phosphorylation and redistribution of the phosphatidylinositol-transfer protein in phorbol 12-myristate 13-acetate- and bombesin-stimulated Swiss mouse 3T3 fibroblasts." Biochemical Journal 291, no. 2 (April 15, 1993): 649–56. http://dx.doi.org/10.1042/bj2910649.

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By immunofluorescence microscopy it was shown that the phosphatidylinositol-transfer protein (PI-TP) becomes associated with the Golgi membranes when confluent (quiescent) Swiss mouse 3T3 fibroblast cells are stimulated with phorbol 12-myristate 13-acetate (PMA) and bombesin. Dibutyryl cyclic AMP or dexamethasone had no effect on the intracellular redistribution of PI-TP. In exponentially growing cells and in serum-starved (semi-quiescent) cells, PI-TP is already associated with Golgi structures. Stimulation of semi-quiescent cells by PMA resulted in a rapid redistribution of PI-TP. A similar yet slower response was observed after stimulation with bombesin. Stimulation of semi-quiescent 3T3 cells by PMA significantly increased the phosphorylation of PI-TP, as shown by immunoprecipitation of PI-TP from pre-labelled cells. No significant increase in phosphorylation of PI-TP was observed after stimulation of these cells by bombesin. Purified PI-TP was shown to be a substrate for protein kinase C in vitro. The possibility that the phosphorylation of PI-TP after activation of protein kinase C is involved in the observed redistribution of PI-TP is discussed.

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Lu, Ling, Yuh-Ru Julie Lee, Ruiqin Pan, Julin N. Maloof, and Bo Liu. "An Internal Motor Kinesin Is Associated with the Golgi Apparatus and Plays a Role in Trichome Morphogenesis in Arabidopsis." Molecular Biology of the Cell 16, no. 2 (February 2005): 811–23. http://dx.doi.org/10.1091/mbc.e04-05-0400.

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Members of the kinesin superfamily are microtubule-based motor proteins that transport molecules/organelles along microtubules. We have identified similar internal motor kinesins, Kinesin-13A, from the cotton Gossypium hirsutum and Arabidopsis thaliana. Their motor domains share high degree of similarity with those of internal motor kinesins of animals and protists in the MCAK/Kinesin13 subfamily. However, no significant sequence similarities were detected in sequences outside the motor domain. In Arabidopsis plants carrying the T-DNA knockout kinesin-13a-1 and kinesin-13a-2 mutations at the Kinesin-13A locus, >70% leaf trichomes had four branches, whereas wild-type trichomes had three. Immunofluorescent results showed that AtKinesin-13A and GhKinesin-13A localized to entire Golgi stacks. In both wild-type and kinesin-13a mutant cells, the Golgi stacks were frequently associated with microtubules and with actin microfilaments. Aggregation/clustering of Golgi stacks was often observed in the kinesin-13a mutant trichomes and other epidermal cells. This suggested that the distribution of the Golgi apparatus in cell cortex might require microtubules and Kinesin-13A, and the organization of Golgi stacks could play a regulatory role in trichome morphogenesis. Our results also indicate that plant kinesins in the MCAK/Kinesin-13 subfamily have evolved to take on different tasks than their animal counterparts.

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Wu, Y. N., M. Gadina, J. H. Tao-Cheng, and R. J. Youle. "Retinoic acid disrupts the Golgi apparatus and increases the cytosolic routing of specific protein toxins." Journal of Cell Biology 125, no. 4 (May 15, 1994): 743–53. http://dx.doi.org/10.1083/jcb.125.4.743.

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All-trans retinoic acid can specifically increase receptor mediated intoxication of ricin A chain immunotoxins more than 10,000 times, whereas fluid phase endocytosis of ricin A chain alone or ricin A chain immunotoxins was not influenced by retinoic acid. The immunotoxin activation by retinoic acid does not require RNA or protein synthesis and is not a consequence of increased receptor binding of the immunotoxin. Vitamin D3 and thyroid hormone T3, that activate retinoic acid receptor (RAR) cognates, forming heterodimers with retinoid X receptor (RXR), do not affect the potency of immunotoxins. Among other retinoids tested, 13-cis retinoic acid, which binds neither RAR nor RXR, also increases the potency of the ricin A chain immunotoxin. Therefore, retinoic acid receptor activation does not appear to be necessary for immunotoxin activity. Retinoic acid potentiation of immunotoxins is prevented by brefeldin A (BFA) indicating that in the presence of retinoic acid, the immunotoxin is efficiently routed through the Golgi apparatus en route to the cytoplasm. Directly examining cells with a monoclonal antibody (Mab) against mannosidase II, a Golgi apparatus marker enzyme, demonstrates that the Golgi apparatus changes upon treatment with retinoic acid from a perinuclear network to a diffuse aggregate. Within 60 min after removal of retinoic acid the cell reassembles the perinuclear Golgi network indistinguishable with that of normal control cells. C6-NBD-ceramide, a vital stain for the Golgi apparatus, shows that retinoic acid prevents the fluorescent staining of the Golgi apparatus and eliminates fluorescence of C6-NBD-ceramide prestained Golgi apparatus. Electron microscopy of retinoic acid-treated cells demonstrates the specific absence of any normal looking Golgi apparatus and a perinuclear vacuolar structure very similar to that seen in monensin-treated cells. This vacuolization disappears after removal of the retinoic acid and a perinuclear Golgi stacking reappears. These results indicate that retinoic acid alters intracellular routing, probably through the Golgi apparatus, potentiating immunotoxin activity indepedently of new gene expression. Retinoic acid appears to be a new reagent to manipulate the Golgi apparatus and intracellular traffic. As retinoic acid and immunotoxins are both in clinical trials for cancer therapy, their combined activity in vivo would be interesting to examine.

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de Figueiredo, P., and W. J. Brown. "A role for calmodulin in organelle membrane tubulation." Molecular Biology of the Cell 6, no. 7 (July 1995): 871–87. http://dx.doi.org/10.1091/mbc.6.7.871.

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Membrane tubules of uniform diameter (60-80 nm) and variable lengths have been seen to extend from the main bodies of the Golgi complex, trans Golgi network (TGN), and endosomes. In the case of endosomes, these tubules appear to mediate membrane and receptor recycling events. Brefeldin A (BFA) is a potent drug that completely blocks coated vesicle formation from the Golgi complex and TGN, but at the same time causes the enhanced formation of membrane tubules from these same organelles. Recently, experiments have shown that calmodulin antagonists inhibit the transport of receptors out of endosomes, perhaps by inhibiting the formation of recycling tubules. Using the potent calmodulin-specific antagonists N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide (W-13), and N-(4-aminobutyl)-5-chloro-1-naphthalenesulfonamide (C-1), we found that the recycling of transferrin from endosomes to the cell surface was significantly inhibited, resulting in the formation of enlarged endosomal vacuoles. In addition, these same calmodulin antagonists also potently inhibited the formation of BFA-stimulated membrane tubules from the Golgi complex, TGN, and endosomes. In the case of the Golgi complex, failure to form tubules resulted in the inhibition of BFA-stimulated retrograde transport to the endoplasmic reticulum. These results suggest that calmodulin is a general regulator of membrane tubulation and is capable of influencing the morphology of several organelles.

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Bertolotti-Ciarlet, Andrea, Jonathan Smith, Karin Strecker, Jason Paragas, Louis A. Altamura, Jeanne M. McFalls, Natalia Frias-Stäheli, Adolfo García-Sastre, Connie S. Schmaljohn, and Robert W. Doms. "Cellular Localization and Antigenic Characterization of Crimean-Congo Hemorrhagic Fever Virus Glycoproteins." Journal of Virology 79, no. 10 (May 15, 2005): 6152–61. http://dx.doi.org/10.1128/jvi.79.10.6152-6161.2005.

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ABSTRACT Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the genus Nairovirus of the family Bunyaviridae, causes severe disease with high rates of mortality in humans. The CCHFV M RNA segment encodes the virus glycoproteins GN and GC. To understand the processing and intracellular localization of the CCHFV glycoproteins as well as their neutralization and protection determinants, we produced and characterized monoclonal antibodies (MAbs) specific for both GN and GC. Using these MAbs, we found that GN predominantly colocalized with a Golgi marker when expressed alone or with GC, while GC was transported to the Golgi apparatus only in the presence of GN. Both proteins remained endo-β-N-acetylglucosaminidase H sensitive, indicating that the CCHFV glycoproteins are most likely targeted to the cis Golgi apparatus. Golgi targeting information partly resides within the GN ectodomain, because a soluble version of GN lacking its transmembrane and cytoplasmic domains also localized to the Golgi apparatus. Coexpression of soluble versions of GN and GC also resulted in localization of soluble GC to the Golgi apparatus, indicating that the ectodomains of these proteins are sufficient for the interactions needed for Golgi targeting. Finally, the mucin-like and P35 domains, located at the N terminus of the GN precursor protein and removed posttranslationally by endoproteolysis, were required for Golgi targeting of GN when it was expressed alone but were dispensable when GC was coexpressed. In neutralization assays on SW-13 cells, MAbs to GC, but not to GN, prevented CCHFV infection. However, only a subset of GC MAbs protected mice in passive-immunization experiments, while some nonneutralizing GN MAbs efficiently protected animals from a lethal CCHFV challenge. Thus, neutralization of CCHFV likely depends not only on the properties of the antibody, but on host cell factors as well. In addition, nonneutralizing antibody-dependent mechanisms, such as antibody-dependent cell-mediated cytotoxicity, may be involved in the in vivo protection seen with the MAbs to GC.

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Vorbroker, D. K., W. F. Voorhout, T. E. Weaver, and J. A. Whitsett. "Posttranslational processing of surfactant protein C in rat type II cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 269, no. 6 (December 1, 1995): L727—L733. http://dx.doi.org/10.1152/ajplung.1995.269.6.l727.

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Pulmonary surfactant consists of phospholipids and proteins that form a stable monolayer at the surface of the alveoli to prevent lung collapse. Surfactant protein C (SP-C) is a hydrophobic 4-kDa palmitoylated protein derived from a 21-kDa precursor. We determined the membrane insertion, proteolytic processing, and subcellular location of 21-kDa proSP-C. In vitro, proSP-C associated with canine microsomes, and the NH2-terminal of proSP-C was protected from digestion with proteinase K, suggesting that proSP-C was inserted in a type III transmembrane configuration. Treatment of freshly isolated rat type II cells with cerulenin blocked acylation of the 21-kDa precursor. Pulse-chase labeling of type II cells demonstrated proSP-C processing intermediates of 19, 16, and 13 kDa that contained the NH2-terminal of proSP-C. Proteolytic processing of proSP-C was inhibited by incubation at 20 degrees C, suggesting that processing of proSP-C begins in a late Golgi or post-Golgi compartment. Immunogold labeling of rat lung with an antiserum to the NH2-terminal of proSP-C identified proSP-C in the trans-Golgi and multivesicular bodies but not in lamellar bodies. These findings suggest that proSP-C processing takes place in the trans-Golgi and multivesicular bodies before SP-C is incorporated into lamellar bodies.

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Sandvig, K., K. Prydz, M. Ryd, and B. van Deurs. "Endocytosis and intracellular transport of the glycolipid-binding ligand Shiga toxin in polarized MDCK cells." Journal of Cell Biology 113, no. 3 (May 1, 1991): 553–62. http://dx.doi.org/10.1083/jcb.113.3.553.

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The glycolipid-binding cytotoxin produced by Shigella dysenteriae 1, Shiga toxin, binds to MDCK cells (strain 1) only after treatment with short-chain fatty acids like butyric acid or with the tumor promoter 12-O-tetradecanoylphorbol 13-acetate. The induced binding sites were found to be functional with respect to endocytosis and translocation of toxin to the cytosol. Glycolipids that bind Shiga toxin appeared at both the apical and the basolateral surface of polarized MDCK cells grown on filters, and Shiga toxin was found to be endocytosed from both sides of the cells. This was demonstrated by EM of cells incubated with Shiga-HRP and by subcellular fractionation of cells incubated with 125I-labeled Shiga toxin. The data indicated that toxin molecules are endocytosed from coated pits, and that some internalized Shiga toxin is transported to the Golgi apparatus. Fractionation of polarized cells incubated with 125I-Shiga toxin showed that the transport of toxin to the Golgi apparatus was equally efficient from both poles of the cells. After 1-h incubation at 37 degrees C approximately 10% of the internalized toxin was found in the Golgi fractions. The results thus suggest that glycolipids can be efficiently transported to the Golgi apparatus from both sides of polarized MDCK cell monolayers.

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Pocognoni, Cristian A., Ekaterina G. Viktorova, John Wright, Justyna M. Meissner, Garrett Sager, Eunjoo Lee, George A. Belov, and Elizabeth Sztul. "Highly conserved motifs within the large Sec7 ARF guanine nucleotide exchange factor GBF1 target it to the Golgi and are critical for GBF1 activity." American Journal of Physiology-Cell Physiology 314, no. 6 (June 1, 2018): C675—C689. http://dx.doi.org/10.1152/ajpcell.00221.2017.

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Cellular life requires the activation of the ADP-ribosylation factors (ARFs) by Golgi brefeldin A-resistant factor 1 (GBF1), a guanine nucleotide exchange factor (GEF) with a highly conserved catalytic Sec7 domain (Sec7d). In addition to the Sec7d, GBF1 contains other conserved domains whose functions remain unclear. Here, we focus on HDS2 (homology downstream of Sec7d 2) domain because the L1246R substitution within the HDS2 α-helix 5 of the zebrafish GBF1 ortholog causes vascular hemorrhaging and embryonic lethality (13). To dissect the structure/function relationships within HDS2, we generated six variants, in which the most conserved residues within α-helices 1, 2, 4, and 6 were mutated to alanines. Each HDS2 mutant was assessed in a cell-based “replacement” assay for its ability to support cellular functions normally supported by GBF1, such as maintaining Golgi homeostasis, facilitating COPI recruitment, supporting secretion, and sustaining cellular viability. We show that cells treated with the pharmacological GBF1 inhibitor brefeldin A (BFA) and expressing a BFA-resistant GBF1 variant with alanine substitutions of RDR1168 or LF1266 are compromised in Golgi homeostasis, impaired in ARF activation, unable to sustain secretion, and defective in maintaining cellular viability. To gain insight into the molecular mechanism of this dysfunction, we assessed the ability of each GBF1 mutant to target to Golgi membranes and found that mutations in RDR1168 and LF1266 significantly decrease targeting efficiency. Thus, these residues within α-helix 2 and α-helix 6 of the HDS2 domain in GBF1 are novel regulatory determinants that support GBF1 cellular function by impacting the Golgi-specific membrane association of GBF1.

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Deretic, D., L. A. Huber, N. Ransom, M. Mancini, K. Simons, and D. S. Papermaster. "rab8 in retinal photoreceptors may participate in rhodopsin transport and in rod outer segment disk morphogenesis." Journal of Cell Science 108, no. 1 (January 1, 1995): 215–24. http://dx.doi.org/10.1242/jcs.108.1.215.

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Small GTP-binding protein rab8 regulates transport from the TGN to the basolateral plasma membrane in epithelial cells and to the dendritic plasma membrane in cultured hippocampal neurons. In our approach to identify proteins involved in rhodopsin transport and sorting in retinal photoreceptors, we have found, using [32P]GTP overlays of 2D gel blots, that six small GTP-binding proteins are tightly bound to the post-Golgi membranes immunoisolated with a mAb to the cytoplasmic domain of frog rhodopsin. We report here that one of these proteins is rab8. About 50% of photoreceptor rab8 is membrane associated and approximately 13% is tightly bound to the post-Golgi vesicles. By confocal microscopy, antibody to rab8 specifically labels calycal processes and the actin bundles of the photoreceptor inner segment that extend inward to the junctional complexes that comprise the outer limiting membrane. Anti-rab8 shows a striking periodicity of high density labeling at 1 +/- 0.12 microns intervals along the actin bundles. Rhodopsin-bearing post-Golgi membranes cluster around the base of the cilium where rab8 and actin are also co-localized, as revealed by confocal microscopy of retinal sections double labeled with anti-rab8 and phalloidin. Microfilaments have been implicated in rod outer segment (ROS) disk morphogenesis. Our data suggest that rab6, which we have previously localized to the post-Golgi compartment, and rab8 associate with the post-Golgi membranes sequentially at different stages of transport. rab8 may mediate later steps that involve interaction of transport membranes with actin filaments and may participate in microfilament-dependent ROS disk morphogenesis.

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Turner, Nancy A., Leticia Nolasco, Zaverio M. Ruggeri, and Joel L. Moake. "Endothelial cell ADAMTS-13 and VWF: production, release, and VWF string cleavage." Blood 114, no. 24 (December 3, 2009): 5102–11. http://dx.doi.org/10.1182/blood-2009-07-231597.

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Abstract Human umbilical vein endothelial cell (HUVEC)–released ADAMTS-13 (a disintegrin and metalloprotease with thrombospondin repeats) and HUVEC-secreted von Willebrand factor (VWF) strings were investigated under static conditions that allow the accumulation and analysis of ADAMTS-13. The latter was released constitutively from HUVECs and cleaved the secreted and cell-anchored VWF strings progressively during 15 minutes in Ca2+/Zn2+-containing buffer. HUVEC ADAMTS13 mRNA expression was approximately 1:100 of VWF monomeric subunit expression. In contrast to multimeric VWF stored within Weibel-Palade bodies and secreted rapidly in response to cell stimulation, ADAMTS-13 was released directly from the Golgi to the cell exterior without an organelle storage site. The constitutive release of ADAMTS-13 continued at the same slow rate regardless of the presence or absence of histamine stimulation of HUVECs. Consequently, the percentage of VWF strings cleaved by ADAMTS-13 at VWF Y1605-M1606 decreased as the rate of VWF string secretion was increased by cell stimulation. Blockade of HUVEC ADAMTS-13 activity by antibodies to different ADAMTS-13 domains made it possible to detect the attachment of ADAMTS-13 all along the lengths of HUVEC-secreted VWF strings. Constitutive ADAMTS-13 released from endothelial cells may contribute to the maintenance of cell surfaces free of hyperadhesive VWF multimeric strings.

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Coonrod, Emily M., and Tom H. Stevens. "The Yeast vps Class E Mutants: The Beginning of the Molecular Genetic Analysis of Multivesicular Body Biogenesis." Molecular Biology of the Cell 21, no. 23 (December 2010): 4057–60. http://dx.doi.org/10.1091/mbc.e09-07-0603.

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In 1992, Raymond et al. published a compilation of the 41 yeast vacuolar protein sorting (vps) mutant groups and described a large class of mutants (class E vps mutants) that accumulated an exaggerated prevacuolar endosome-like compartment. Further analysis revealed that this “class E compartment” contained soluble vacuolar hydrolases, vacuolar membrane proteins, and Golgi membrane proteins unable to recycle back to the Golgi complex, yet these class E vps mutants had what seemed to be normal vacuoles. The 13 class E VPS genes were later shown to encode the proteins that make up the complexes required for formation of intralumenal vesicles in late endosomal compartments called multivesicular bodies, and for the sorting of ubiquitinated cargo proteins into these internal vesicles for eventual delivery to the vacuole or lysosome.

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Fitriani, Fitriani, Yulida Amri, Syamsul Bahri, and Fara Nadilla. "Response of Seed Bioinvoguration with Plant Growth Promoting Rhizobacteria (PGPR) on Growth and Productivity of Rice gogo." BIOEDUSCIENCE 5, no. 1 (April 23, 2021): 57–61. http://dx.doi.org/10.22236/j.bes/515739.

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Background: Gogo rice is a type of rice that can be cultivated on dry land with a yield productivity level of 2.57 tons / Ha. So it is necessary to make efforts to increase the growth and productivity of gogo rice through seed bio-inviguration using PGPR. The purpose of this study was to determine the effect of beni bioinviguration techniques using PGPR on the growth and productivity of gogo rice. Method: This study used a RAK consisting of 7 treatments and 5 replications. Data analysis used ANOVA at the 5% confidence level and continued with the BNT test. Result: The results showed that the use of biomatriconditioning medium integrated with PGPR could increase the stem height of upland rice by 104.2 cm, 117 cm, and 133.3, the number of tillers were 7, 13 and 15 at the age of 8, 10, and 12 MST. In addition, it can also increase the number of panicles, the length and weight of 100 grains of 14, 22.6 cm and 2.1 grams. Conclusion: the use of biomatriconditioning medium integrated with PGPR can increase the growth and productivity of gogo rice.

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Brandon, Elizabeth, Tomasz Szul, Cecilia Alvarez, Robert Grabski, Ronald Benjamin, Ryoichi Kawai, and Elizabeth Sztul. "On and Off Membrane Dynamics of the Endoplasmic Reticulum–Golgi Tethering Factor p115 In Vivo." Molecular Biology of the Cell 17, no. 7 (July 2006): 2996–3008. http://dx.doi.org/10.1091/mbc.e05-09-0862.

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The mechanisms regulating membrane recruitment of the p115 tethering factor in vivo are unknown. Here, we describe cycling of p115 between membranes and cytosol and document the effects of Golgi matrix proteins, Rab1, and soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein (SNAP) receptors (SNAREs) on this process. Rapid membrane/cytosol exchange is shown by swift (t1/2 ∼20 s) loss of Golgi-localized p115-green fluorescent protein (GFP) after repeated photobleaching of cell periphery and rapid (t1/2 ∼13 s) fluorescence recovery after photobleaching Golgi-localized p115-GFP. p115 mutant missing the GM130/giantin binding site exhibits analogous fluorescence recovery after photobleaching (FRAP) (t1/2 ∼13 s), suggesting that GM130 and giantin are not major determinants of p115 membrane dynamics. In contrast, p115-GFP exchanges more rapidly (t1/2 ∼8 s) in cells expressing the inactive Rab1/N121I mutant, indicating that p115 cycling is influenced by Rab1. p115-GFP dynamics is also influenced by the assembly status of SNAREs. In cells expressing an ATPase-deficient NSF/E329Q mutant that inhibits SNARE complex disassembly, the cycling kinetics of p115-GFP are significantly slower (t1/2 ∼21 s). In contrast, in cells incubated at reduced temperature (10°C) that inhibits vesicular traffic, the cycling kinetics of p115-GFP are faster (t1/2 ∼7 s). These data suggest that p115-binding sites on the membrane are provided by unassembled SNAREs. In agreement, biochemical studies show increased p115 recruitment to membranes in the presence of NSF and α-SNAP. Our data support a model in which recruitment of tethers is directly regulated by the assembly status of SNAREs.

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Sotnikov, Oleg, Tat'yana Kokurina, and Galina Rybakova. "Golgi black reaction and the history of the study of living axons." MORPHOLOGICAL NEWSLETTER 25, no. 3 (September 30, 2017): 8–13. http://dx.doi.org/10.20340/mv-mn.17(25).03.8-13.

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32

Romero Fereira, Patricia, Dwight Arrieche, Vanessa Acosta, Luis Perez, and Cesar Lodeiros. "Ciclo gametogenico de la ostra Pinctada imbricata en cultivo suspendido en el Golfo de Cariaco, Venezuela." Latin American Journal of Aquatic Research 45, no. 1 (March 10, 2017): 139–48. http://dx.doi.org/10.3856/vol45-issue1-fulltext-13.

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Frescas, David, Manos Mavrakis, Holger Lorenz, Robert DeLotto, and Jennifer Lippincott-Schwartz. "The secretory membrane system in the Drosophila syncytial blastoderm embryo exists as functionally compartmentalized units around individual nuclei." Journal of Cell Biology 173, no. 2 (April 24, 2006): 219–30. http://dx.doi.org/10.1083/jcb.200601156.

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Drosophila melanogaster embryogenesis begins with 13 nuclear division cycles within a syncytium. This produces >6,000 nuclei that, during the next division cycle, become encased in plasma membrane in the process known as cellularization. In this study, we investigate how the secretory membrane system becomes equally apportioned among the thousands of syncytial nuclei in preparation for cellularization. Upon nuclear arrival at the cortex, the endoplasmic reticulum (ER) and Golgi were found to segregate among nuclei, with each nucleus becoming surrounded by a single ER/Golgi membrane system separate from adjacent ones. The nuclear-associated units of ER and Golgi across the syncytial blastoderm produced secretory products that were delivered to the plasma membrane in a spatially restricted fashion across the embryo. This occurred in the absence of plasma membrane boundaries between nuclei and was dependent on centrosome-derived microtubules. The emergence of secretory membranes that compartmentalized around individual nuclei in the syncytial blastoderm is likely to ensure that secretory organelles are equivalently partitioned among nuclei at cellularization and could play an important role in the establishment of localized gene and protein expression patterns within the early embryo.

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Radau, Boris, Albrecht Otto, Eva-Christina Müller, and Peter Westermann. "Protein kinase Cα-dependent phosphorylation of Golgi proteins." Electrophoresis 21, no. 13 (July 1, 2000): 2684–87. http://dx.doi.org/10.1002/1522-2683(20000701)21:13<2684::aid-elps2684>3.0.co;2-g.

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Banton, M. C., K. L. Inder, E. Valk, C. E. Rudd, and H. Schneider. "Rab8 Binding to Immune Cell-Specific Adaptor LAX Facilitates Formation of trans-Golgi Network-Proximal CTLA-4 Vesicles for Surface Expression." Molecular and Cellular Biology 34, no. 8 (February 10, 2014): 1486–99. http://dx.doi.org/10.1128/mcb.01331-13.

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Zhang, Rui, Zhi Zhu, Wenzhuang Shen, Xingrui Li, Deenraj Kush Dhoomun, and Yao Tian. "Golgi Membrane Protein 1 (GOLM1) Promotes Growth and Metastasis of Breast Cancer Cells via Regulating Matrix Metalloproteinase-13 (MMP13)." Medical Science Monitor 25 (January 29, 2019): 847–55. http://dx.doi.org/10.12659/msm.911667.

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37

Sano, Toshiaki, Kalman Kovacs, Sylvia L. Asa, Shozo Yamada, Naoko Sanno, Shunichi Yokoyama, and Hiroshi Takami. "Pituitary Adenoma with "Honeycomb Golgi" Appearance Showing a Phenotypic Change at Recurrence from Clinically Nonfunctioning to Typical Cushing Disease." Endocrine Pathology 13, no. 2 (2002): 125–30. http://dx.doi.org/10.1385/ep:13:2:125.

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38

Sørensen, Jakob B. "Ride the wave: Retrograde trafficking becomes Ca2+ dependent with BAIAP3." Journal of Cell Biology 216, no. 7 (June 16, 2017): 1887–89. http://dx.doi.org/10.1083/jcb.201706007.

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The functions of four of the five proteins in the mammalian uncoordinated-13 (Munc13) family have been identified as priming factors in SNARE-dependent exocytosis. In this issue, Zhang et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201702099) show that the fifth member, BAIAP3 (brain-specific angiogenesis inhibitor I–associated protein 3), acts in retrograde trafficking by returning secretory vesicle material to the trans-Golgi network. In its absence, secretory vesicle formation is impaired, leading to accumulation of immature vesicles, or lysosomal vesicle degradation.

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Weise, F., Y. D. Stierhof, C. Kuhn, M. Wiese, and P. Overath. "Distribution of GPI-anchored proteins in the protozoan parasite Leishmania, based on an improved ultrastructural description using high-pressure frozen cells." Journal of Cell Science 113, no. 24 (December 15, 2000): 4587–603. http://dx.doi.org/10.1242/jcs.113.24.4587.

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The cellular distribution of two glycosyl-phosphatidylinositol (GPI)-anchored proteins and a trans-membrane protein and the compartments involved in their trafficking were investigated in the insect stage of Leishmania mexicana, which belongs to the phylogenetically old protozoan family Trypanosomatidae. Electron microscopy of sections from high-pressure frozen and freeze-substituted cells allowed a detailed description of exo- and endocytic structures located in the vesicle-rich, densely packed anterior part of the spindle-shaped cell. A complex of tubular clusters/translucent vesicles is the prominent structure between the trans-side of the single Golgi apparatus and the flagellar pocket, the only site of endo- and exocytosis. A tubulovesicular compartment lined by one or two distinct microtubules and extending along the length of the cell is proposed to be a post-Golgi and probably late endosomal/lysosomal compartment. Using biotinylation experiments, FACS analysis and quantitative immunoelectron microscopy it was found that, at comparable expression levels, 73–75% of the two GPI-anchored proteins but only 13% of the trans-membrane protein are located on the cell surface. The tubulovesicular compartment contains 46%, the ER 5%, the Golgi complex 1.9% and the tubular cluster/translucent vesicle complex 3.6% of the intracellular fraction of the GPI-anchored protease, GP63. The density of GP63 was found to be 23-fold higher on the plasma/flagellar pocket membrane than on the ER and about tenfold higher than on membranes of the Golgi complex or of endo- or exocytic vesicles. These results indicate that there is a considerable concentration gradient of GPI-anchored proteins between the plasma/flagellar pocket membrane and the ER as well as structures involved in exo- or endocytosis. Possible mechanisms how this concentration gradient is established are discussed.

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Yoshimura, Shin-ichiro, Andreas Gerondopoulos, Andrea Linford, Daniel J. Rigden, and Francis A. Barr. "Family-wide characterization of the DENN domain Rab GDP-GTP exchange factors." Journal of Cell Biology 191, no. 2 (October 11, 2010): 367–81. http://dx.doi.org/10.1083/jcb.201008051.

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A key requirement for Rab function in membrane trafficking is site-specific activation by GDP-GTP exchange factors (GEFs), but the majority of the 63 human Rabs have no known GEF. We have performed a systematic characterization of the 17 human DENN domain proteins and demonstrated that they are specific GEFs for 10 Rabs. DENND1A/1B localize to clathrin patches at the plasma membrane and activate Rab35 in an endocytic pathway trafficking Shiga toxin to the trans-Golgi network. DENND2 GEFs target to actin filaments and control Rab9-dependent trafficking of mannose-6-phosphate receptor to lysosomes. DENND4 GEFs target to a tubular membrane compartment adjacent to the Golgi, where they activate Rab10, which suggests a function in basolateral polarized sorting in epithelial cells that compliments the non-DENN GEF Sec2 acting on Rab8 in apical sorting. DENND1C, DENND3, DENND5A/5B, MTMR5/13, and MADD activate Rab13, Rab12, Rab39, Rab28, and Rab27A/27B, respectively. Together, these findings provide a basis for future studies on Rab regulation and function.

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Santos, P. R. S., M. F. Oliveira, M. A. M. Arroyo, A. R. Silva, R. E. G. Rici, M. A. Miglino, and A. C. Assis Neto. "Ultrastructure of spermatogenesis in Spix's yellow-toothed cavy (Galea spixii)." REPRODUCTION 147, no. 1 (January 2014): 13–19. http://dx.doi.org/10.1530/rep-13-0452.

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This was a pioneer study of the spermatogenic process from the onset of puberty in Spix's yellow-toothed cavies (SYC,Galea spixii) bred in captivity. The study aimed to characterize fine structure of spermatogenesis. Twelve testes from pubertal and post-pubertal SYC males were studied using transmission electron microscopy. Spermatogenesis can be divided into three phases: proliferation, meiosis, and spermiogenesis. In proliferation phase, three types of spermatogonia were identified and characterized as Adark, Apale, and B. In the second phase, spermatocytes (2n) undergo meiotic divisions that generate spermatids (n); the process begins in spermatocytes in the preleptotene stage when they increase their nuclear size, differentiating into spermatocytes in the leptotene stage when cell division is initiated. In addition, we found chromatin condensation, and formation of a structure composed of proteins that formed a central shaft and two lateral bars associated with pairing of homologous chromosomes. During spermiogenesis, the following main events occurred: condensation of nuclear chromatin, formation of acrosome with perfuratorium, elimination of residual cytoplasm, and development of the flagellum. The sperm head is different from that of other rodents. The endoplasmic reticulum and the Golgi complex are the two main organelles demonstrated during this process. These organelles collaborate through synthesis of proteins and hormones for the development of germ cells during spermatogenesis in SYC.

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Yamaoka, Tomomi, Kazuki Imada, Kana Fukunishi, Yuriko Yamasaki, Chikashi Shimoda, and Taro Nakamura. "The Fission Yeast Synaptobrevin Ortholog Syb1 Plays an Important Role in Forespore Membrane Formation and Spore Maturation." Eukaryotic Cell 12, no. 9 (May 24, 2013): 1162–70. http://dx.doi.org/10.1128/ec.00061-13.

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ABSTRACTSynaptobrevin, also called vesicle-associated membrane protein (VAMP), is a component of the plasma membrane N-methylmaleimide-sensitive factor attachment protein receptor (SNARE) complex, which plays a key role in intracellular membrane fusion. Previous studies have revealed that, similar to synaptobrevin in other organisms, the fission yeast synaptobrevin ortholog Syb1 associates with post-Golgi secretory vesicles and is essential for cytokinesis and cell elongation. Here, we report that Syb1 has a role in sporulation. After nitrogen starvation, green fluorescent protein (GFP)-Syb1 is found in intracellular dots. As meiosis proceeds, GFP-Syb1 accumulates around the nucleus and then localizes at the forespore membrane (FSM). We isolated asyb-S1mutant, which exhibits a defect in sporulation. Insyb1-S1mutants, the FSM begins to form but fails to develop a normal morphology. Electron microscopy shows that an abnormal spore wall is often formed insyb1-S1mutant spores. Although mostsyb1-S1mutant spores are germinated, they are less tolerant to ethanol than wild-type spores. Thesyb1-S1allele carries a missense mutation, resulting in replacement of a conserved cysteine residue adjacent to the transmembrane domain, which reduces the stability and abundance of the Syb1 protein. Taken together, these results indicate that Syb1 plays an important role in both FSM assembly and spore wall formation.

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Devarajan, P., P. R. Stabach, A. S. Mann, T. Ardito, M. Kashgarian, and J. S. Morrow. "Identification of a small cytoplasmic ankyrin (AnkG119) in the kidney and muscle that binds beta I sigma spectrin and associates with the Golgi apparatus." Journal of Cell Biology 133, no. 4 (May 15, 1996): 819–30. http://dx.doi.org/10.1083/jcb.133.4.819.

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Ankyrins are a family of large, membrane-associated proteins that mediate the linkage of the cytoskeleton to a variety of membrane transport and receptor proteins. A repetitive 33-residue motif characteristic of domain I of ankyrin has also been identified in proteins involved with cell cycle control and development. We have cloned and characterized a novel ankyrin isoform, AnkG119 (GenBank accession No. U43965), from the human kidney which lacks part of this repetitive domain and associates in MDCK cells with beta I sigma spectrin and the Golgi apparatus, but not the plasma membrane. Sequence comparison reveals this ankyrin to be an alternative transcript of AnkG, a much larger ankyrin recently cloned from brain. AnkG119 has a predicted size of 119,201 D, and contains a 47-kD domain I consisting of 13 ankyrin repeat units, a 67-kD domain II with a highly conserved spectrin-binding motif, and a truncated 5-kD putative regulatory domain. An AnkG119 cDNA probe hybridized to a 6.0-kb message in human and rat kidney, placenta, and skeletal muscle. An antibody raised to AnkG119 recognized an apparent 116-kD peptide in rat kidney cortical tissue and MDCK cell lysates, and did not react with larger isoforms of ankyrin at 190 and 210 kD in these tissues, nor in bovine brain, nor with ankyrin from human erythrocytes. AnkG119 remains extractable in 0.5% Triton X-100, and assumes a punctuate cytoplasmic distribution in mature MDCK cells, in contrast to the Triton-stable plasma membrane localization of all previously described renal ankyrins. AnkG119 immunocreativity in subconfluent MDCK cells distributes with the Golgi complex in a pattern coincident with beta -COP and beta I sigma spectrin immunoreactivity. A fusion peptide containing residues 669-860 of AnkG119 interacts with beta I sigma 1 spectrin in vitro with a Kd = 4.2 +/- 4.0 ( +/- 2 SD) nM, and avidly binds the beta spectrin in MDCK cell lysates. Collectively, these data identify AnkG119 as a novel small ankyrin that binds and colocalizes with beta I sigma spectrin in the ER and Golgi apparatus, and possible on a subset of endosomes during the early stages of polarity development. We hypothesize that AnkG119 and beta I spectrin form a vesicular Golgi-associated membrane skeleton, promote the organization of protein microdomains within the Golgi and trans-Golgi networks, and contribute to polarized vesicle transport.

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BREEDY, ODALISCA, and HECTOR M. GUZMAN. "A new species of Leptogorgia (Cnidaria: Anthozoa: Octocorallia) from Golfo Dulce, Pacific, Costa Rica." Zootaxa 3182, no. 1 (February 3, 2012): 65. http://dx.doi.org/10.11646/zootaxa.3182.1.7.

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The description of this single species is necessary to facilitate the publication of ongoing research conducted by Rita Vargas at the Museum of Zoology, University of Costa Rica, dealing with the associated microfauna. Presently 24 species of Leptogorgia have been reported for the eastern Pacific, 13 of which have been found in Costa Rica (Breedy & Cortés 2011). Although octocoral surveys have been conducted as part of biodiversity studies, there is no published information regarding the occurrence of this taxon in Golfo Dulce. Here we describe a new species of Leptogorgia and compare it with other Leptogorgia species with similar characteristics. Golfo Dulce is a bay located on the southern Pacific coast of Costa Rica. It is about 50 km long, 10–15 km wide, and covers an area of approximately 680 km². The inner part of Golfo Dulce has a maximum depth of slightly over 200 m with a 60 m deep sill at the opening to the Pacific Ocean (Cortés 1999). It has been considered a tropical fjord because of the bathymetry and the presence of anoxic deep waters (Cortés 1999, Svendsen et al. 2006). Specimens were collected by Scuba diving, preserved in 70% ethanol or air dried, and treated and identified following the current methodology (Breedy & Guzman 2002). The holotype and paratypes are deposited in the Museo de Zoología, Universidad de Costa Rica (MZUCR, formerly UCR), San José, P.O. Box 11501-2060, Costa Rica.

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Zhang, Junbing, Jinchao Liu, Anne Norris, Barth D. Grant, and Xiaochen Wang. "A novel requirement for ubiquitin-conjugating enzyme UBC-13 in retrograde recycling of MIG-14/Wntless and Wnt signaling." Molecular Biology of the Cell 29, no. 17 (August 15, 2018): 2098–112. http://dx.doi.org/10.1091/mbc.e17-11-0639.

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After endocytosis, transmembrane cargoes such as signaling receptors, channels, and transporters enter endosomes where they are sorted to different destinations. Retromer and ESCRT (endosomal sorting complex required for transport) are functionally distinct protein complexes on endosomes that direct cargo sorting into the recycling retrograde transport pathway and the degradative multivesicular endosome pathway (MVE), respectively. Cargoes destined for degradation in lysosomes are decorated with K63-linked ubiquitin chains, which serve as an efficient sorting signal for entry into the MVE pathway. Defects in K63-linked ubiquitination disrupt MVE sorting and degradation of membrane proteins. Here, we unexpectedly found that UBC-13, the E2 ubiquitin-conjugating enzyme that generates K63-linked ubiquitin chains, is essential for retrograde transport of multiple retromer-dependent cargoes including MIG-14/Wntless. Loss of ubc-13 disrupts MIG-14/Wntless trafficking from endosomes to the Golgi, causing missorting of MIG-14 to lysosomes and impairment of Wnt-dependent processes. We observed that retromer-associated SNX-1 and the ESCRT-0 subunit HGRS-1/Hrs localized to distinct regions on a common endosome in wild type but overlapped on ubc-13(lf) endosomes, indicating that UBC-13 is important for the separation of retromer and ESCRT microdomains on endosomes. Our data suggest that cargo ubiquitination mediated by UBC-13 plays an important role in maintaining the functionally distinct subdomains to ensure efficient cargo segregation on endosomes.

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Griffiths, G., and H. Hoppeler. "Quantitation in immunocytochemistry: correlation of immunogold labeling to absolute number of membrane antigens." Journal of Histochemistry & Cytochemistry 34, no. 11 (November 1986): 1389–98. http://dx.doi.org/10.1177/34.11.3534077.

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Baby hamster kidney cells infected with Semliki Forest virus were used as a model system for quantitative immunocytochemical labeling studies. In this system, a well-characterized membrane protein complex is present in different concentrations in three separate locations. Using immunogold labeling of cryosections, we compared the number of gold particles labeling the membranes of endoplasmic reticulum, Golgi stack, and fully formed virions at the plasma membrane to the biochemically determined concentrations. The efficiency of labeling was 40, 13, and 14% for the three structures, respectively. In a comparative study, Lowicryl K4M sections were found to give significantly lower levels of labeling.

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Rizzo, Juliana, Débora L. Oliveira, Luna S. Joffe, Guanggan Hu, Felipe Gazos-Lopes, Fernanda L. Fonseca, Igor C. Almeida, Susana Frases, James W. Kronstad, and Marcio L. Rodrigues. "Role of the Apt1 Protein in Polysaccharide Secretion by Cryptococcus neoformans." Eukaryotic Cell 13, no. 6 (December 13, 2013): 715–26. http://dx.doi.org/10.1128/ec.00273-13.

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ABSTRACTFlippases are key regulators of membrane asymmetry and secretory mechanisms. Vesicular polysaccharide secretion is essential for the pathogenic mechanisms ofCryptococcus neoformans. On the basis of the observations that flippases are required for polysaccharide secretion in plants and the putative Apt1 flippase is required for cryptococcal virulence, we analyzed the role of this enzyme in polysaccharide release byC. neoformans, using a previously characterizedapt1Δ mutant. Mutant and wild-type (WT) cells shared important phenotypic characteristics, including capsule morphology and dimensions, glucuronoxylomannan (GXM) composition, molecular size, and serological properties. Theapt1Δ mutant, however, produced extracellular vesicles (EVs) with a lower GXM content and different size distribution in comparison with those of WT cells. Our data also suggested a defective intracellular GXM synthesis in mutant cells, in addition to changes in the architecture of the Golgi apparatus. These findings were correlated with diminished GXM production duringin vitrogrowth, macrophage infection, and lung colonization. This phenotype was associated with decreased survival of the mutant in the lungs of infected mice, reduced induction of interleukin-6 (IL-6) cytokine levels, and inefficacy in colonization of the brain. Taken together, our results indicate that the lack ofAPT1caused defects in both GXM synthesis and vesicular export to the extracellular milieu byC. neoformansvia processes that are apparently related to the pathogenic mechanisms used by this fungus during animal infection.

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Liu, Yaoping, Norma V. Solis, Clemens J. Heilmann, Quynh T. Phan, Aaron P. Mitchell, Frans M. Klis, and Scott G. Filler. "Role of Retrograde Trafficking in Stress Response, Host Cell Interactions, and Virulence of Candida albicans." Eukaryotic Cell 13, no. 2 (December 20, 2013): 279–87. http://dx.doi.org/10.1128/ec.00295-13.

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ABSTRACTInSaccharomyces cerevisiae, the vacuolar protein sorting complexes Vps51/52/53/54 and Vps15/30/34/38 are essential for efficient endosome-to-Golgi complex retrograde transport. Here we investigated the function of Vps15 and Vps51, representative members of these complexes, in the stress resistance, host cell interactions, and virulence ofCandida albicans. We found thatC. albicansvps15Δ/Δ andvps51Δ/Δ mutants had abnormal vacuolar morphology, impaired retrograde protein trafficking, and dramatically increased susceptibility to a variety of stressors. These mutants also had reduced capacity to invade and damage oral epithelial cellsin vitroand attenuated virulence in the mouse model of oropharyngeal candidiasis. Proteomic analysis of the cell wall of thevps51Δ/Δ mutant revealed increased levels of the Crh11 and Utr2 transglycosylases, which are targets of the calcineurin signaling pathway. The transcript levels of the calcineurin pathway membersCHR11,UTR2,CRZ1,CNA1, andCNA2were elevated in thevps15Δ/Δ andvps51Δ/Δ mutants. Furthermore, these strains were highly sensitive to the calcineurin-specific inhibitor FK506. Also, deletion ofCHR11andUTR2further increased the stress susceptibility of these mutants. In contrast, overexpression ofCRH11andUTR2partially rescued their defects in stress resistance, but not host cell interactions. Therefore, intact retrograde trafficking inC. albicansis essential for stress resistance, host cell interactions, and virulence. Aberrant retrograde trafficking stimulates the calcineurin signaling pathway, leading to the increased expression of Chr11 and Utr2, which enablesC. albicansto withstand environmental stress.

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Tokuda, Emi, Toshiki Itoh, Junya Hasegawa, Takeshi Ijuin, Yukiko Takeuchi, Yasuhiro Irino, Miki Fukumoto, and Tadaomi Takenawa. "Phosphatidylinositol 4-Phosphate in the Golgi Apparatus Regulates Cell–Cell Adhesion and Invasive Cell Migration in Human Breast Cancer." Cancer Research 74, no. 11 (April 4, 2014): 3054–66. http://dx.doi.org/10.1158/0008-5472.can-13-2441.

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Piper, Robert C., Nia J. Bryant, and Tom H. Stevens. "The Membrane Protein Alkaline Phosphatase Is Delivered to the Vacuole by a Route That Is Distinct from the VPS-dependent Pathway." Journal of Cell Biology 138, no. 3 (August 11, 1997): 531–45. http://dx.doi.org/10.1083/jcb.138.3.531.

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Membrane trafficking intermediates involved in the transport of proteins between the TGN and the lysosome-like vacuole in the yeast Saccharomyces cerevisiae can be accumulated in various vps mutants. Loss of function of Vps45p, an Sec1p-like protein required for the fusion of Golgi-derived transport vesicles with the prevacuolar/endosomal compartment (PVC), results in an accumulation of post-Golgi transport vesicles. Similarly, loss of VPS27 function results in an accumulation of the PVC since this gene is required for traffic out of this compartment. The vacuolar ATPase subunit Vph1p transits to the vacuole in the Golgi-derived transport vesicles, as defined by mutations in VPS45, and through the PVC, as defined by mutations in VPS27. In this study we demonstrate that, whereas VPS45 and VPS27 are required for the vacuolar delivery of several membrane proteins, the vacuolar membrane protein alkaline phosphatase (ALP) reaches its final destination without the function of these two genes. Using a series of ALP derivatives, we find that the information to specify the entry of ALP into this alternative pathway to the vacuole is contained within its cytosolic tail, in the 13 residues adjacent to the transmembrane domain, and loss of this sorting determinant results in a protein that follows the VPS-dependent pathway to the vacuole. Using a combination of immunofluorescence localization and pulse/chase immunoprecipitation analysis, we demonstrate that, in addition to ALP, the vacuolar syntaxin Vam3p also follows this VPS45/27-independent pathway to the vacuole. In addition, the function of Vam3p is required for membrane traffic along the VPS-independent pathway.

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Journal articles on the topic 'Golgo 13'

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