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Journal articles on the topic 'Germinal vesicle'

Author: Grafiati
Published: 4 June 2021
Last updated: 25 April 2022

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1

Sorensen, R. A., M. S. Cyert, and R. A. Pedersen. "Active maturation-promoting factor is present in mature mouse oocytes." Journal of Cell Biology 100, no. 5 (May 1, 1985): 1637–40. http://dx.doi.org/10.1083/jcb.100.5.1637.

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Cytoplasmic extracts of meiotically mature mouse oocytes were injected into immature Xenopus laevis oocytes, which underwent germinal vesicle breakdown within 2 h. Germinal vesicle breakdown was not inhibited by incubation of the Xenopus oocytes in cycloheximide (20 micrograms/ml). Identically prepared extracts of meiotically immature mouse oocytes, arrested at the germinal vesicle stage by dibutyryl cyclic AMP (100 micrograms/ml), did not induce germinal vesicle breakdown in Xenopus oocytes. The results show that maturation-promoting factor activity appears during the course of oocyte maturation in the mouse.
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2

Wessel, Gary M. "“Origin” of the germinal vesicle." Molecular Reproduction and Development 77, no. 4 (April 2010): NA. http://dx.doi.org/10.1002/mrd.21168.

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3

Wu, Zheng'an, and Joseph G. Gall. "“Micronucleoli” in theXenopus germinal vesicle." Chromosoma 105, no. 7-8 (June 1997): 438–43. http://dx.doi.org/10.1007/bf02510480.

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4

CHIBA, KAZUYOSHI, and MOTONORI HOSHI. "Mass Isolation of Germinal Vesicles from Starfish Oocytes*. (germinal vesicle/nucleus/oocyte/starfish/mass isolation)." Development, Growth and Differentiation 27, no. 3 (June 1985): 277–82. http://dx.doi.org/10.1111/j.1440-169x.1985.00277.x.

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5

Gall, J. "Structure in the amphibian germinal vesicle." Experimental Cell Research 296, no. 1 (May 15, 2004): 28–34. http://dx.doi.org/10.1016/j.yexcr.2004.03.017.

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6

Wu, Zheng'an, and Joseph G. Gall. "”Micronucleoli" in the Xenopus germinal vesicle." Chromosoma 105, no. 7-8 (June 10, 1997): 438–43. http://dx.doi.org/10.1007/s004120050205.

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7

Huo, Li-Jun, Cheng-Guang Liang, Ling-Zhu Yu, Zhi-Sheng Zhong, Zeng-Ming Yang, Heng-Yu Fan, Da-Yuan Chen, and Qing-Yuan Sun. "Inducible nitric oxide synthase-derived nitric oxide regulates germinal vesicle breakdown and first polar body emission in the mouse oocyte." Reproduction 129, no. 4 (April 2005): 403–9. http://dx.doi.org/10.1530/rep.1.0542.

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The present study investigated the subcellular localization of inducible nitric oxide synthase (iNOS) during mouse oocyte meiotic maturation and fertilization using confocal microscopy, and further studied the roles of iNOS-derived NO in oocyte maturation by using an iNOS-specific inhibitor aminoguanidine (AG) and iNOS antibody microinjection. In germinal vesicle-stage oocytes, iNOS immunoreactivity was mainly localized in the germinal vesicle. Shortly after germinal vesicle breakdown, the iNOS immunoreactivity accumulated around the condensed chromosomes. At metaphase I and metaphase II, with the organization of chromosomes to the equatorial plate, iNOS immunoreactivity was concentrated around the aligned chromosomes, putatively the position of the metaphase spindle. The accumulation of iNOS immunoreactivity could not be detected at anaphase I and anaphase II. However, at telophase I and telophase II, the staining of iNOS was concentrated in the region between the separating chromosomes/chromatids. Furthermore, the staining of iNOS also accumulated in the male and female pronuclei in fertilized eggs. Germinal vesicle breakdown and the first polar body emission of the oocytes were significantly blocked by the iNOS-specific inhibitor AG in a dose-dependent manner. The germinal vesicle breakdown in oocytes injected with iNOS antibody was also inhibited. We found that the phosphorylation of mitogen-activated protein kinase in oocytes after germinal vesicle breakdown was inhibited by AG treatment. The control oocytes extruded a normal first polar body, while the AG-treated oocytes exhibited an elongated protrusion or no elongated protrusion. The results of confocal microscopy showed that the AG-treated oocytes were arrested at anaphase I–telophase I. Our results suggest that the iNOS-derived NO pathway plays important roles in mouse oocyte meiotic maturation, especially in germinal vesicle breakdown and the anaphase–telophase transition.
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8

Gavin, A. C., J. C. Cavadore, and S. Schorderet-Slatkine. "Histone H1 kinase activity, germinal vesicle breakdown and M phase entry in mouse oocytes." Journal of Cell Science 107, no. 1 (January 1, 1994): 275–83. http://dx.doi.org/10.1242/jcs.107.1.275.

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Meiotic reinitiation of the mouse oocyte is characterized by a slow entry into metaphase I, beginning with germinal vesicle breakdown and ending with spindle formation. It is accompanied by a cascade of protein kinases and phosphatases increasing protein phosphorylation. The activation of histone H1 kinase and that of the mitogen-activated protein kinase p42 have been compared during spontaneous or okadaic acid-induced meiotic reinitiation. In spontaneously maturing oocytes, histone H1 kinase activity increases before germinal vesicle breakdown (2-fold), in a protein synthesis-independent manner. It is associated with the disappearance of the upper migrating form of p34cdc2, which, in our system, seems to represent the tyrosine phosphorylated form. Following germinal vesicle breakdown, histone H1 kinase activity culminates (8-fold) in metaphase I and requires protein synthesis. Activation by phosphorylation of p42MAPK is observed as a permanent shift upward-migrating form and by its myelin basic protein kinase activity. It occurs after germinal vesicle breakdown and depends on protein synthesis. In contrast, no increase of histone H1 kinase is detectable in oocytes induced to reinitiate meiosis by a transient inhibition of okadaic acid-sensitive phosphatase(s), either before germinal vesicle breakdown or during the following 7 hours of culture. A slight increase is nevertheless evident after 17 hours, when oocytes are arrested with an abnormal metaphase I spindle. The upper migrating form of p34cdc2 is present for 8 hours. The activation of p42MAPK begins before germinal vesicle breakdown.(ABSTRACT TRUNCATED AT 250 WORDS)
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9

Takahashi, Y., C. Goto, and K. K. Kita. "Ultrastructural study of Trichinella spiralis with emphasis on adult male reproductive organs." Journal of Helminthology 68, no. 4 (December 1994): 353–58. http://dx.doi.org/10.1017/s0022149x00001632.

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AbstractThe ultrastructure of the reproductive system of adult male Trichinella spiralis has been examined, particularly to assist in recent advances such as the localization of target antigens of protective immunity and the mode of immune attack. The male reproductive system consists of a single tube with a hairpin-like bend, composed of a basal lamina, epithelial cells, rachis, circumferential and constrictor muscles, and germinal cells. The organs were surrounded by basal lamina and haemolymph. Germinal cells in different stages of maturation were found on the wall of the testis along its entire length. As the maturation of germinal cells proceeded, the cells moved towards the lumen of the testis. The germinal cells had a row of vesicles (cup-shaped structures) at the cell periphery. The mature sperm, lacking flagella and an acrosome, were stored in the seminal vesicle. The cytoplasm of the epithelial cells of the seminal vesicle and ejaculatory duct was filled with distended rough endoplasmic reticulum (rER) and exocrine granules which appeared homogenous and of medium electron density. The granules appeared to discharge to the lumen.
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10

Inoue, Maki, Kunihiko Naito, Taisuke Nakayama, and Eimei Sato. "Mitogen-Activated Protein Kinase Translocates into the Germinal Vesicle and Induces Germinal Vesicle Breakdown in Porcine Oocytes1." Biology of Reproduction 58, no. 1 (January 1, 1998): 130–36. http://dx.doi.org/10.1095/biolreprod58.1.130.

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11

Terasaki, M. "Redistribution of cytoplasmic components during germinal vesicle breakdown in starfish oocytes." Journal of Cell Science 107, no. 7 (July 1, 1994): 1797–805. http://dx.doi.org/10.1242/jcs.107.7.1797.

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The starfish oocyte is relatively clear optically, and its nucleus, termed the germinal vesicle, is large. These characteristics allowed studies by confocal microscopy of germinal vesicle breakdown during maturation in living oocytes. Three fluorescent probes for cytoplasmic components were used: fluorescein 70 kDa dextran, which does not cross the nuclear pore of immature oocytes and probably behaves in the same way as soluble cytosolic proteins, YOYO-1, which was used to localize ribosomes, and DiI which labels the nuclear envelope and endoplasmic reticulum. The first change observable by transmitted light microscopy during maturation is a wrinkling of the germinal vesicle envelope. Several minutes before the wrinkling, the 70 kDa dextran began to enter the germinal vesicle; the ribosomes did not enter during this period. The dextran is likely to be passing through nuclear pores whose size limit has increased but which still exclude ribosomes. At the time of the wrinkling of the germinal vesicle envelope, both 70 kDa dextran and ribosomes entered as a massive wave. The characteristics of this entry indicate that the permeability barrier of the nuclear envelope bilayer has been disrupted. The disruption of the permeability barrier occurred in a local region rather than around the entire periphery. Also, the disruption was observed more often on the animal pole side of the germinal vesicle (26/34 oocytes). The endoplasmic reticulum entered the nuclear region more slowly. Cytochalasin B inhibited this movement and also inhibited characteristic endoplasmic reticulum movements seen at high magnification. The effects of cytochalasin indicate that mixing of endoplasmic reticulum with nuclear space is an active process involving actin filaments.
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12

Papaioannidou, P. G., A. Borini, S. Garetti, M. A. Bonu, and C. Flamigni. "In vitro maturation of germinal vesicle oocytes." Fertility and Sterility 76, no. 3 (September 2001): S231. http://dx.doi.org/10.1016/s0015-0282(01)02689-9.

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13

Takeuchi, Takumi, Zev Rosenwaks, and Gianpiero D. Palermo. "Preimplantation development of germinal vesicle recipient oocytes." Fertility and Sterility 78 (September 2002): S102—S103. http://dx.doi.org/10.1016/s0015-0282(02)03651-8.

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14

Bar-Joseph, Hadas, Irit Ben-Aharon, Salomon M. Stemmer, Moran Tzabari, and Ruth Shalgi. "Doxorubicin-Induced Apoptosis in Germinal Vesicle Oocytes." Biology of Reproduction 81, Suppl_1 (July 1, 2009): 83. http://dx.doi.org/10.1093/biolreprod/81.s1.83.

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15

Liu, Yong, Hong-Shu Sui, Hui-Li Wang, Ji-Hong Yuan, Ming-Jiu Luo, Ping Xia, and Jing-He Tan. "Germinal vesicle chromatin configurations of bovine oocytes." Microscopy Research and Technique 69, no. 10 (August 2, 2006): 799–807. http://dx.doi.org/10.1002/jemt.20349.

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16

Liu, Ji-Long, Michael Buszczak, and Joseph G. Gall. "Nuclear bodies in the Drosophila germinal vesicle." Chromosome Research 14, no. 4 (May 2006): 465–75. http://dx.doi.org/10.1007/s10577-006-1062-5.

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17

Galas, S., H. Barakat, M. Dorée, and A. Picard. "A nuclear factor required for specific translation of cyclin B may control the timing of first meiotic cleavage in starfish oocytes." Molecular Biology of the Cell 4, no. 12 (December 1993): 1295–306. http://dx.doi.org/10.1091/mbc.4.12.1295.

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In most animals, the rate of cyclin B synthesis increases after nuclear envelope breakdown during the first meiotic cell cycle. We have found that cyclin B-cdc2 kinase activity drops earlier in emetine-treated than in control starfish oocytes, although the protein synthesis inhibitor does not activate the cyclin degradation pathway prematurely. Moreover, protein synthesis is required to prevent meiotic cleavage to occur prematurely, sometimes before chromosomes have segregated on the metaphase plate. In normal conditions, increased synthesis of cyclin B after germinal vesicle breakdown (GVBD) balances cyclin degradation and increases the time required for cyclin B-cdc2 kinase to drop below the level that inhibits cleavage. Taken together, these results point to cyclin B as a possible candidate that could explain the need for increased protein synthesis during meiosis I. Although direct experimental evidence was not provided in the present work, cyclin B synthesis after GVBD may be important for correct segregation of homologous chromosomes at the end of first meiotic metaphase, as shown by a variety of cytological disorders that accompany premature cleavage. Although the overall stimulation of protein synthesis because of cdc2 kinase activation is still observed in oocytes from which the germinal vesicle has been removed before hormonal stimulation, the main increase of cyclin B synthesis normally observed after germinal vesicle breakdown is suppressed. The nuclear factor required for specific translation of cyclin B after GVBD is not cyclin B mRNA, as shown by using a highly sensitive reverse transcription followed by polymerase chain reaction procedure that failed to detect any cyclin B mRNA in isolated germinal vesicles.
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18

Marshall, William S., Hamid R. Habibi, and Charles A. Lessman. "Electrophysiology of oocytes during meiotic maturation and after ovulation in brook trout (Salvelinus fontinalis)." Canadian Journal of Zoology 63, no. 8 (August 1, 1985): 1904–8. http://dx.doi.org/10.1139/z85-283.

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Brook trout oocytes were stripped of their follicular layers and were impaled with both voltage-measuring and current-passing microelectrodes. The membrane resting potential (Vm) was −46 ± 1.2 mV (mean ± SE, n = 50, bath grounded) in control denuded oocytes with an intact germinal vesicle. Vm was reduced to −38 ± 1.8 mV (n = 16) in eggs that had ovulated in vivo. Accompanying the potential drop was a marked increase in membrane resistance (Rm) from 26 ± 1.7 in denuded oocytes to 1640 ± 150 kΩ∙cm2 in ovulated eggs and a reduction in membrane current (Im) from 2380 ± 260 to 25 ± 2.6 nA∙cm2. The increased resistance in ovulated eggs was in part the result of reduced Na+ and K+ membrane conductances; there was no significant change in Cl− conductance. Treatment of denuded oocytes with 17α-20β-dihydroxyprogesterone produced germinal vesicle dissolution; in denuded oocytes that had undergone germinal vesicle dissolution in vitro, Rm increased and Im decreased, comparable at least qualitatively to the changes seen after ovulation in vivo. The results indicate that major electrophysiological changes accompany germinal vesicle dissolution and ovulation in brook trout oocytes.
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19

Kiessling, A. A., and S. Markoulaki. "Inhibiting Phosphodiesterase Activity to Maintain Germinal Vesicle Stage Arrest Inhibits DNA Strand Breaks in Germinal Vesicle Stage Mouse Oocytes." Fertility and Sterility 74, no. 3 (September 2000): S4. http://dx.doi.org/10.1016/s0015-0282(00)00733-0.

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20

Kim, Nam-Hyung, Seong Koo Cho, Seok Hwa Choi, Eun Young Kim, Se Pill Park, and Jin Ho Lim. "The distribution and requirements of microtubules and microfilaments in bovine oocytes during in vitro maturation." Zygote 8, no. 1 (February 2000): 25–32. http://dx.doi.org/10.1017/s0967199400000794.

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Microtubules and microfilaments are major cytoskeletal components and important modulators for chromosomal movement and cellular division in mammalian oocytes. In this study we observed microtubule and microfilament organisation in bovine oocytes by laser scanning confocal microscopy, and determined requirements of their assembly during in vitro maturation. After germinal vesicle breakdown, small microtubular asters were observed near the condensed chromatin. The asters appeared to elongate and encompass condensed chromatin particles. At the metaphase stage, microtubules were observed in the second meiotic spindle at the metaphase stage. The meiotic spindle was a symmetrical, barrel-shaped structure containing anastral broad poles, located peripherally and radially oriented. Treatment with nocodazole did not inhibit germinal vesicle breakdown. However, progression to metaphase failed to occur in oocytes treated with nocodazole. In contrast, microfilaments were observed as a relatively thick uniform area around the cell cortex and overlying chromatin following germinal vesicle breakdown. Treatment with cytochalasin B inhibited microfilament polymerisation but did not prevent either germinal vesicle breakdown or metaphase formation. However, movement of chromatin to the proper position was inhibited in oocytes treated with cytochalasin B. These results suggest that both microtubules and microfilaments are closely associated with reconstruction and proper positioning of chromatin during meiotic maturation in bovine oocytes.
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21

Memili, E., D. Peddinti, L. A. Shack, B. Nanduri, F. McCarthy, H. Sagirkaya, and S. C. Burgess. "Bovine germinal vesicle oocyte and cumulus cell proteomics." Reproduction 133, no. 6 (June 2007): 1107–20. http://dx.doi.org/10.1530/rep-06-0149.

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Germinal vesicle (GV) breakdown is fundamental for maturation of fully grown, developmentally competent, mammalian oocytes. Bidirectional communication between oocytes and surrounding cumulus cells (CC) is essential for maturation of a competent oocyte. However, neither the factors involved in this communication nor the mechanisms of their actions are well defined. Here, we define the proteomes of GV oocytes and their surrounding CC, including membrane proteins, using proteomics in a bovine model. We found that 4395 proteins were expressed in the CC and 1092 proteins were expressed in oocytes. Further, 858 proteins were common to both the CC and the oocytes. This first comprehensive proteome analysis of bovine oocytes and CC not only provides a foundation for signaling and cell physiology at the GV stage of oocyte development, but are also valuable for comparative studies of other stages of oocyte development at the molecular level. Furthermore, some of these proteins may represent molecular biomarkers for developmental potential of oocytes.
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22

Gable, T. L., and G. L. Woods. "Confocal microscopy of germinal vesicle-stage equine oocytes." Theriogenology 55, no. 7 (April 2001): 1417–30. http://dx.doi.org/10.1016/s0093-691x(01)00491-5.

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23

Bar-Joseph, Hadas, Irit Ben-Aharon, Shulamith Rizel, Salomon M. Stemmer, Moran Tzabari, and Ruth Shalgi. "Doxorubicin-induced apoptosis in germinal vesicle (GV) oocytes☆." Reproductive Toxicology 30, no. 4 (December 2010): 566–72. http://dx.doi.org/10.1016/j.reprotox.2010.07.003.

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24

Hiradate, Yuuki, Jun Ohtake, Yumi Hoshino, Kentaro Tanemura, and Eimei Sato. "Adrenomedullin: A possible regulator of germinal vesicle breakdown." Biochemical and Biophysical Research Communications 415, no. 4 (December 2011): 691–95. http://dx.doi.org/10.1016/j.bbrc.2011.10.139.

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25

Kalmbach, K., and D. L. Keefe. "Telomere attrition in germinal vesicle arrested human oocytes." Fertility and Sterility 104, no. 3 (September 2015): e199. http://dx.doi.org/10.1016/j.fertnstert.2015.07.617.

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26

Benc, Michal, Josef Jr Fulka, František Strejček, Martin Morovič, Matej Murín, Stanislava Martínková, Dominika Jettmarová, and Jozef Laurinčík. "Enucleolation and nucleolus transfer in mammalian oocytes and zygotes." International Journal of Developmental Biology 63, no. 3-4-5 (2019): 253–58. http://dx.doi.org/10.1387/ijdb.190002mb.

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The oocyte GV/GVs (germinal vesicle/germinal vesicles) and zygot PN/PNs (pronucleus/pronuclei) of some mammals contain clearly visible nucleoli which exhibit an atypical morphological structure. These nucleoli (NCLs) can be relatively easily manipulated, i.e. removed from GVs/PNs or eventually transferred into another oocyte/zygote. Thus, with the help of micromanipulation techniques it was possible to uncover the real function(s) they play in processes of oocyte maturation and early embryonic development. The purpose of our review is to describe briefly the micromanipulation techniques that can be used for oocyte/zygote nucleoli manipulation. Moreover, we present some examples of results that were obtained in nucleolus manipulation experiments.
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27

Herlands, Louis, and Gerd G. Maul. "Characterization of a Major Nucleoplasmin-like Germinal Vesicle Protein Which Is Rapidly Phosphorylated before Germinal Vesicle Breakdown in Spisula solidissima." Developmental Biology 161, no. 2 (February 1994): 530–37. http://dx.doi.org/10.1006/dbio.1994.1051.

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28

Ohan, N., Y. Agazie, C. Cummings, R. Booth, M. Bayaa, and X. J. Liu. "RHO-associated protein kinase alpha potentiates insulin-induced MAP kinase activation in Xenopus oocytes." Journal of Cell Science 112, no. 13 (July 1, 1999): 2177–84. http://dx.doi.org/10.1242/jcs.112.13.2177.

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We recently identified Xenopus Rho-associated protein kinase alpha (xROKalpha) as a Xenopus insulin receptor substrate-1 binding protein and demonstrated that the non-catalytic carboxyl terminus of xROKalpha binds Xenopus insulin receptor substrate-1 and blocks insulin-induced MAP kinase activation and germinal vesicle breakdown in Xenopus oocytes. In the current study we further examined the role of xROKalpha in insulin signal transduction in Xenopus oocytes. We demonstrate that injection of mRNA encoding the xROKalpha kinase domain or full length xROKalpha enhanced insulin-induced MAP kinase activation and germinal vesicle breakdown. In contrast, injection of a kinase-dead mutant of xROKalpha or pre-incubation of oocytes with an xROKalpha inhibitor significantly reduced insulin-induced MAP kinase activation. To further dissect the mechanism by which xROKalpha may participate in insulin signalling, we explored a potential function of xROKalpha in regulating cellular Ras function, since insulin-induced MAP kinase activation and germinal vesicle breakdown is known to be a Ras-dependent process. We demonstrate that whereas injection of mRNA encoding c-H-Ras alone induced xMAP kinase activation and GVBD in a very low percentage (about 10%) of injected oocytes, co-injection of mRNA encoding xROKalpha and c-H-Ras induced xMAP kinase activation and germinal vesicle breakdown in a significantly higher percentage (50-60%) of injected oocytes. These results suggest a novel function for xROKalpha in insulin signal transduction upstream of cellular Ras function.
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29

Berg, L. K., and G. M. Wessel. "Cortical granules of the sea urchin translocate early in oocyte maturation." Development 124, no. 9 (May 1, 1997): 1845–50. http://dx.doi.org/10.1242/dev.124.9.1845.

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Cortical granules are secretory vesicles poised at the cortex of an egg that, upon stimulation by sperm contact at fertilization, secrete their contents. These contents modify the extracellular environment and block additional sperm from reaching the egg. The role of cortical granules in blocking polyspermy is conserved throughout much of phylogeny. In the sea urchin, cortical granules accumulate throughout the cytoplasm during oogenesis, but in mature eggs the cortical granules are attached to the plasma membrane, having translocated to the cortex at some earlier time. To study the process of cortical granule translocation to the cell surface we have devised a procedure for maturation of sea urchin oocytes in vitro. Using this procedure, we examined the rate of oocyte maturation by observing the movement and breakdown of the germinal vesicle, the formation of polar bodies and the formation of the egg pronucleus. We find that oocyte maturation takes approximately 9 hours in the species used here (Lytechinus variegatus), from the earliest indication of maturation (germinal vesicle movement) to formation of a distinct pronucleus. We then observed the translocation of cortical granules in these cells by immunolocalization using a monoclonal antibody to hyalin, a protein packaged specifically in cortical granules. We found that the translocation of cortical granules in in vitro-matured oocytes begins with the movement of the germinal vesicle to the oocyte cell surface, and is 50% complete 1 hour after germinal vesicle breakdown. In the in vitro-matured egg, 99% of the cortical granules are at the cortex, indistinguishable from translocation in oocytes that mature in vivo. We have also found that eggs that mature in vitro are functionally identical to eggs that mature in vivo by four criteria. (1) The matured cells undergo a selective turnover of mRNA encoding cortical granule contents. (2) The newly formed pronucleus begins transcription of histone messages. (3) Cortical granules that translocate in vitro are capable of exocytosis upon activation by the calcium ionophore, A23187. (4) The mature egg is fertilizable and undergoes normal cleavage and development. In vitro oocyte maturation enables us to examine the mechanism of cortical granule translocation and other processes that had previously only been observed in static sections of fixed ovaries.
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30

Rubin, E. J., D. M. Gill, P. Boquet, and M. R. Popoff. "Functional modification of a 21-kilodalton G protein when ADP-ribosylated by exoenzyme C3 of Clostridium botulinum." Molecular and Cellular Biology 8, no. 1 (January 1988): 418–26. http://dx.doi.org/10.1128/mcb.8.1.418.

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Exoenzyme C3 from Clostridium botulinum types C and D specifically ADP-ribosylated a 21-kilodalton cellular protein, p21.bot. Guanyl nucleotides protected the substrate against denaturation, which implies that p21.bot is a G protein. When introduced into the interior of cells, purified exoenzyme C3 ADP-ribosylated intracellular p21.bot and changed its function. NIH 3T3, PC12, and other cells rapidly underwent temporary morphological alterations that were in certain respects similar to those seen after microinjection of cloned ras proteins. When injected into Xenopus oocytes, C3 induced migration of germinal vesicles and potentiated the cholera toxin-sensitive augmentation of germinal vesicle breakdown by progesterone, also as caused by ras proteins. Nevertheless, p21.bot was immunologically distinct from p21ras.
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31

Rubin, E. J., D. M. Gill, P. Boquet, and M. R. Popoff. "Functional modification of a 21-kilodalton G protein when ADP-ribosylated by exoenzyme C3 of Clostridium botulinum." Molecular and Cellular Biology 8, no. 1 (January 1988): 418–26. http://dx.doi.org/10.1128/mcb.8.1.418-426.1988.

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Exoenzyme C3 from Clostridium botulinum types C and D specifically ADP-ribosylated a 21-kilodalton cellular protein, p21.bot. Guanyl nucleotides protected the substrate against denaturation, which implies that p21.bot is a G protein. When introduced into the interior of cells, purified exoenzyme C3 ADP-ribosylated intracellular p21.bot and changed its function. NIH 3T3, PC12, and other cells rapidly underwent temporary morphological alterations that were in certain respects similar to those seen after microinjection of cloned ras proteins. When injected into Xenopus oocytes, C3 induced migration of germinal vesicles and potentiated the cholera toxin-sensitive augmentation of germinal vesicle breakdown by progesterone, also as caused by ras proteins. Nevertheless, p21.bot was immunologically distinct from p21ras.
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32

Jantsch, M. F., and J. G. Gall. "Assembly and localization of the U1-specific snRNP C protein in the amphibian oocyte." Journal of Cell Biology 119, no. 5 (December 1, 1992): 1037–46. http://dx.doi.org/10.1083/jcb.119.5.1037.

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To study the intranuclear localization of the U1-specific snRNP C protein and its assembly into U1 snRNPs, we injected transcripts encoding a myc-tagged C protein into amphibian oocytes. The distribution of protein translated from the injected RNA was essentially the same in continuous and pulse-label experiments. In both cases the C protein localized within the germinal vesicle in those structures known to contain U1 snRNPs, namely the lampbrush chromosome loops and hundreds of extrachromosomal granules called snurposomes. Oocytes were also injected with an antisense oligodeoxynucleotide that caused truncation of U1 snRNA at the 5' end. In these oocytes, myc-tagged C protein localized normally in the germinal vesicle and could be immunoprecipitated together with truncated U1 snRNA. These experiments suggest that the C protein can enter the germinal vesicle on its own and there associate with previously assembled U1 snRNPs. In transfected tissue culture cells, the myc-tagged C protein localized within the nucleus in a speckled pattern similar to that of endogenous U1 snRNPs.
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33

Carotenuto, R., G. Maturi, V. Infante, T. Capriglione, T. C. Petrucci, and C. Campanella. "A novel protein cross-reacting with antibodies against spectrin is localised in the nucleoli of amphibian oocytes." Journal of Cell Science 110, no. 21 (November 1, 1997): 2683–90. http://dx.doi.org/10.1242/jcs.110.21.2683.

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Cytoskeletal proteins such as actin and myosin are important constituents of the nucleoplasm. Spectrin is an actin binding protein typically related to plasma membrane; recently, it has been found that it is widespread and forms distinct membrane protein domains in such organelles as the Golgi. In this paper, the large germinal vesicle of amphibian oocytes was chosen as a particularly suitable system to investigate the presence and location of spectrin in the nucleus. We manually isolated the germinal vesicles of both Discoglossus pictus and Xenopus laevis oocytes, and processed them for SDS-PAGE, immunoblotting and immunoprecipitation. By the use of an antibody against the general form of brain beta spectrin (betaIIsigma1) and of an anti-alpha brain spectrin (alphaIIsigma*), a band of 230 kDa was identified as a nuclear spectrin-like molecule. Moreover the 230 kDa protein was extracted from the nuclei by 1 M KCl, similarly to spectrin in other systems. In oocyte sections and nuclear spreads incubated with anti-alphaIIsigma* and/or anti-betaIIsigma1 antibodies, the immunostain was localised in the nucleoplasm and in the outer shell of the round bodies abundantly present in the germinal vesicle. Sections of the same oocytes, stained with a monoclonal antibody against nucleolar fibrillarin and anti-alphaIIsigma*, showed co-localisation of the two antibodies. It was concluded that, in the germinal vesicle of amphibian oocytes, a spectrin-like molecule is a part of the outer shell of nucleoli. It is hypothesised that spectrin, together with actin, might be instrumental in keeping nucleoli attached to the inner nuclear membrane, as nucleoli migrate during oogenesis to the inner aspect of the nuclear envelope, where they are stably kept until the end of their growth. Furthermore, these results strongly suggest that the 230 kDa band might comprise both an alpha and a beta chain of the same apparent molecular mass, thus constituting a novel form of a spectrin-like molecule.
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34

Cruz-Landim, C., and K. Patrício. "Nuclear activity in Apis mellifera L. (Hymenoptera, Apidae) queen ovary cells demonstrated by silver nitrate impregnation and ultrastructure." Brazilian Journal of Biology 70, no. 4 (November 2010): 1069–73. http://dx.doi.org/10.1590/s1519-69842010000500023.

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The present paper shows through conventional light microscopy, silver nitrate impregnation and Transmission Electron Microscopy, the changes in nuclear activity that occurs in the ovary cells during vitellogenesis of Apis mellifera (Linnaeus, 1758). The material impregnated by silver nitrate was detected in nurse cells, oocyte germinal vesicle and follicular cells, whose amounts are greater in phases corresponding to ovarian cells more intense activity. The silver impregnation permitted to demonstrate that the oocyte germinal vesicle synthezises ribonucleoproteins (RNP) during the beginning of the vitellogenesis. The ultrastructure show nucleolar-like material corresponding to nuclear sites impregnated by silver.
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35

Ming, TengXiao, HansIngolf Nielsen, and ZhiQin Chen. "Maturation arrest of human oocytes at germinal vesicle stage." Journal of Human Reproductive Sciences 3, no. 3 (2010): 153. http://dx.doi.org/10.4103/0974-1208.74161.

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36

Brunet, Stéphane, and Bernard Maro. "Germinal vesicle position and meiotic maturation in mouse oocyte." Reproduction 133, no. 6 (June 2007): 1069–72. http://dx.doi.org/10.1530/rep-07-0036.

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During meiotic maturation, mammalian oocytes undergo an asymmetric division which is crucial for the formation of a functional gamete. In various organisms, accurate positioning of the nucleus before M-phase plays a major role in asymmetric cell divisions. However, the role of the position of the nucleus (or germinal vesicle, GV) during the prophase I arrest has not been investigated in mammalian oocytes. Here, we show that incompetent mouse oocytes possess a peripheral GV, while competent oocytes mainly exhibit a central position of the GV. At that time, the position of the GV correlates with the ability of the oocyte to complete meiotic maturation. Moreover, a lower efficiency in GV centering and a reduced ability to progress through meiosis are observed in oocytes from old mice. Thus, the position of the GV could be used as a simple morphological marker of oocyte quality.
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37

Abeydeera, Lalantha R., Kiyoshi Okuda, and Koji Niwa. "Activation of bovine oocytes penetrated after germinal vesicle breakdown." Zygote 2, no. 4 (November 1994): 273–79. http://dx.doi.org/10.1017/s0967199400002094.

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SummaryThe present study was designed to examine the ability of bovine oocytes, after germinal vesicle breakdown (GVBD), to be activated by sperm penetration and the sequence of sperm nuclear transformation. Bovine oovytes cultured for 8 h in maturation medium (tissue culture medium TCM-199 containing 10% fetal calf serum) were inseminated in Brackett and Oilphant's medium supplemented with bovine serum albumin (10 mg/ml), caffeine (5mM) and heparin (10 μg/ml). When oocytes were transferrred to the maturation medium 8 h after insemination and additionally cultured for 5−40 h at 39°C in 5% CO2 in air, 71−76% of oocytes were penetrated and polyspermy (67–75%) was common. The proportions of penetrated oocytes that were activated significantly increased with the lapse of the additional culture time, reaching 88% and 87% by 25 and 40 h after additional culture, respectively. When compared with unpenetrated oocytes, signifcantly higher proportions of penetrated oocytes, reached metaphase II or beyond 15 and 25 h after additional culture. After penetration, sperm nuclei were transformed into metaphase chromosomes and then to telophase chromomes before the formation of male pronuclei. These results provide evidence that bovine oocytes acquire the ability to respond to sperm-mediated activation soon after GVBD.
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38

Haberle, M., Ph Scheurer, K. Lauerer, M. Flacher, and M. K. Hohl. "Can germinal vesicle oocytes from stimulated cycles mature spontaneously?" Human Reproduction 13, suppl 4 (December 1, 1998): 286. http://dx.doi.org/10.1093/humrep/13.suppl_4.286.

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39

Tan, J. H., H. L. Wang, X. S. Sun, Y. Liu, H. S. Sui, and J. Zhang. "Chromatin configurations in the germinal vesicle of mammalian oocytes." Molecular Human Reproduction 15, no. 1 (November 18, 2008): 1–9. http://dx.doi.org/10.1093/molehr/gan069.

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40

Canesin, H. S., I. Ortiz, J. G. Brom-de-Luna, Y. H. Choi, and K. Hinrichs. "43 MASS VITRIFICATION OF GERMINAL-VESICLE STAGE EQUINE OOCYTES." Reproduction, Fertility and Development 28, no. 2 (2016): 151. http://dx.doi.org/10.1071/rdv28n2ab43.

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Oocyte cryopreservation has the potential to preserve female genetics. In addition, equine oocytes are not readily available in some areas, and vitrification could be used to accumulate oocytes at remote locations to provide material for research. To preserve large numbers of oocytes, a method for rapid vitrification of multiple oocytes is needed. First, we determined whether immature equine oocytes could be held overnight before vitrification, and we tested the use of a mesh+capillary-action media-removal vitrification platform. Oocytes were collected via ultrasound-guided transvaginal follicle aspiration and randomly allotted to either immediate vitrification or overnight holding (24 to 27 h in 40% M199-Earle’s salts, 40% M199-Hanks’ salts, 20% fetal bovine serum, and 0.3 mM pyruvate) then vitrification. Oocytes were vitrified using different times (1 or 4 min) in vitrification solution and first warming solution: 1v1w, 1v4w, 4v1w, and 4v4w. The base solution was MH (80% M199-Hanks’ salts and 20% fetal bovine serum). Cryoprotectant concentration (vol/vol) was increased in 3 steps until reaching 7.5% dimethyl sulfoxide and 7.5% ethylene glycol. The oocytes were then held in vitrification solution (MH with 15% dimethyl sulfoxide, 15% ethylene glycol, and 0.5 M sucrose) for either 1 or 4 min, according to treatment, and 3 to 10 oocytes were transferred to a 75-μm sterile stainless steel mesh. The mesh was placed on sterile paper to absorb excess medium, then plunged in LN. The oocytes were warmed in MH solution with 1.25 M sucrose for either 1 or 4 min, then placed in 0.62 M and 0.31 M sucrose solutions for 5 min each and undetermined time in MH. After warming, oocytes were cultured for maturation (in vitro maturation) in M199-Earle’s salts, 5 mU mL–1 FSH, and 10% fetal bovine serum. After 30 to 36 h, the oocytes were denuded and stained with Hoechst 33258. Data were analysed by Fisher’s exact test. There were no significant differences (P > 0.05) in rates of meiotic resumption among timing treatments (35, 24, 26, and 39% for 1v1w, 1v4w, 4v1w, and 4v4w, respectively), nor between immediately vitrified (17/55, 31%) and overnight held-vitrified groups (18/56, 32%). In the second experiment, all oocytes were held overnight. They were vitrified and warmed using only the 1v1w and 4v4w schedules, then subjected to in vitro maturation, intracytoplasmic sperm injection, and embryo culture. The MII rate of the control group (27/37, 73%) was higher (P < 0.05) than that for 1v1w (12/33, 36%) or 4v4w treatments (10/35, 29%). The cleavage rate for control (25/27, 93%) was higher than that for 1v1w (5/9, 56%) but not than that for 4v4w (6/9, 67%). Blastocyst rates were 19% (5/27), 11% (1/9), and 0% (0/9) for control, 1v1w, and 4v4w, respectively (P > 0.05). These results indicate that blastocysts may be produced from equine immature oocytes vitrified en masse; however, both the maturation and blastocyst production rates were relatively low. Additional studies are required to improve the efficiency of this technique. This work was supported by the Clinical Equine ICSI Program, Texas A&M University.
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41

Moor, R. M., and I. M. Crosby. "Protein requirements for germinal vesicle breakdown in ovine oocytes." Development 94, no. 1 (June 1, 1986): 207–20. http://dx.doi.org/10.1242/dev.94.1.207.

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The regulation of the cell cycle during the transition from prophase to metaphase I was studied by analysing protein changes and introducing protein blocks during the transition phase. The results show that the progression to metaphase in ovine oocytes is totally dependent on new protein synthesis. By delaying the addition of the inhibitor, cycloheximide, for progressively longer periods after the resumption of meiosis it was established that the required synthesis occurs in the 1–2 h immediately preceding germinal vesicle breakdown (GVBD). The action of cycloheximide was fully reversible: removal of the drug resulted in GVBD between 3 and 4h later. The synthesis and modification of proteins during these first few hours of maturation were studied by short-term radiolabelling of oocytes with [35S]methionine and [32P]phosphate followed by rapid assessment of their precise nuclear configuration. Changes in phosphorylation of two polypeptides were detected 4–5 h after the beginning of culture, but these changes were not dependent upon protein synthesis. The earliest change in synthesis was the appearance of a new polypeptide 6–8 h after explantation, immediately before GVBD. This polypeptide (Mr 47×103, pI 5·8) was not significantly phosphorylated and was relatively stable. Oocytes released from cycloheximide treatment began to synthesize this molecule 3–4 h later, again coinciding with GVBD. Synthesis of the polypeptide was suppressed by inhibition of transcription with α-amanitin.
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42

Yan, Li-Ying, Jun-Cheng Huang, Zi-Yu Zhu, Zi-Li Lei, Li-Hong Shi, Chang-Long Nan, Zhen-Jun Zhao, et al. "NuMA distribution and microtubule configuration in rabbit oocytes and cloned embryos." Reproduction 132, no. 6 (December 2006): 869–76. http://dx.doi.org/10.1530/rep.1.01224.

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The assembly of microtubules and the distribution of NuMA were analyzed in rabbit oocytes and early cloned embryos. α-Tubulin was localized around the periphery of the germinal vesicle (GV). After germinal vesicle breakdown (GVBD), multi-arrayed microtubules were found tightly associated with the condensed chromosomes and assembled into spindles. After the enucleated oocyte was fused with a fibroblast, microtubules were observed around the introduced nucleus in most reconstructed embryos and formed a transient spindle 2–4 h post-fusion (hpf). A mass of microtubules surrounded the swollen pseudo-pronucleus 5 hpf and a normal spindle was formed 13 hpf in cloned embryos. NuMAwas detected in the nucleus in germinal vesicle-stage oocytes, and it was concentrated at the spindle poles in both meiotic and mitotic metaphase. In both donor cell nucleus and enucleated oocyte cytoplasm, NuMA was not detected, while NuMA reappeared in pseudo-pronucleus as reconstructed embryo development proceeded. However, no evident NuMA staining was observed in the poles of transient spindle and first mitotic spindle in nuclear transfer eggs. These results indicate that NuMA localization and its spindle pole tethering function are different during rabbit oocyte meiosis and cloned embryo mitosis.
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43

Zhang, Ze, Baobao Chen, Haoliang Cui, Haixu Gao, Ming Gao, and Chenyu Tao. "Dynamic alterations in H4K12 acetylation during meiotic maturation and after parthenogenetic activation of mouse oocytes." Zygote 28, no. 5 (July 23, 2020): 367–70. http://dx.doi.org/10.1017/s0967199420000192.

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SummaryThe aim of the study was to investigate the continuous changing pattern of H4K12 acetylation, and the expression levels of histone acetyltransferases (HATs) and histone deacetyltransferases (HDACs) in mouse oocytes during meiosis and after parthenogenetic activation (PA). The immunofluorescence results showed hyperacetylation of lysine-12 on histone H4 (H4K12) in the germinal vesicle (GV) oocytes that then decreased during germinal vesicle breakdown (GVBD), and disappeared in metaphase II (MII). However, it reappeared in the early 1-cell embryos derived after 4 h of PA. The expression levels of some selected HATs and HDACs also validated the changing pattern of H4K12 acetylation during meiosis and PA. In conclusion, H4K12 is deacetylated in GVBD and MII, and re-hyperacetylated after PA.
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44

Gibbs, J. B., M. D. Schaber, T. L. Schofield, E. M. Scolnick, and I. S. Sigal. "Xenopus oocyte germinal-vesicle breakdown induced by [Val12]Ras is inhibited by a cytosol-localized Ras mutant." Proceedings of the National Academy of Sciences 86, no. 17 (September 1989): 6630–34. http://dx.doi.org/10.1073/pnas.86.17.6630.

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The GTPase-activating protein (GAP) has been postulated to function either as a negative regulator or as a possible target protein of Ras in mammalian cells and Xenopus oocytes. Ras must be localized in the plasma membrane of vertebrate cells to function, but GAP is localized in the cytosol. To test whether Ras function depends on a cytosolic factor such as GAP, we microinjected into Xenopus oocytes a form of Saccharomyces cerevisiae RAS1 ([Leu68]RAS1 terminated at residue 185, called [Leu68]RAS1(term.] that lacks the consensus membrane localization site, does not respond to GAP in a GTPase assay, but binds to GAP 100-fold more tightly than [Val12]Ras. [Leu68]RAS1(term.) alone did not stimulate oocyte germinal-vesicle breakdown. Instead, [Leu68]RAS1(term.) was observed to inhibit the action of insulin-like growth factor 1 or microinjected [Val12]Ras but not the action of progesterone as monitored by germinal-vesicle breakdown. Coinjection of purified mammalian GAP with [Leu68]RAS1(term.) reduced the inhibition of [Val12]Ras-stimulated germinal-vesicle breakdown. The results raise the possibility that a cytosolic factor is required for the action of [Val12]Ras in Xenopus oocytes and that this factor is either GAP or another protein with which GAP can compete for binding to [Leu68]RAS1(term.).
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45

Laidlaw, M., and G. M. Wessel. "Cortical granule biogenesis is active throughout oogenesis in sea urchins." Development 120, no. 5 (May 1, 1994): 1325–33. http://dx.doi.org/10.1242/dev.120.5.1325.

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Cortical granules are secretory vesicles formed in the eggs of most animals and are essential for the prevention of polyspermy in these organisms. We have studied the biogenesis of cortical granules in sea urchin oocytes by identifying cDNA clones that encode proteins targeted selectively to the cortical granules. These cDNA clones were identified by an immunoscreen of a cDNA library using antibodies to proteins of the fertilization envelope. Four different mRNAs were identified, ranging from 4 kb to 13 kb in length, that encoded proteins targeted specifically to cortical granules. Accumulation of these mRNAs began very early in oogenesis, in oocytes approximately 10–15 microns in diameter, and continued throughout oogenesis. The mRNAs reached peak abundance (on a per cell basis) in germinal vesicle stage oocytes, and the accumulation of each mRNA was linear with respect to oocyte growth. During breakdown of the germinal vesicle these mRNAs were degraded so that in eggs the mRNA signals were at background levels. Antibodies generated to recombinant proteins made from each of these cDNA clones showed that in the oocyte each cognate protein appeared early in oogenesis. These proteins accumulated only in cortical granules: no accumulation was seen in the cytoplasm, in Golgi, or in other vesicles, and no heterogeneity of the contents was seen within the population of cortical granules. Using these antibodies we show that cortical granules accumulated linearly throughout oogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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46

Oosaki, Eriko, Manabu Sugii, and Masahiro Fujishima. "Purification of germinal-vesicle-breakdown-inducing proteins from Tetrahymena pyriformis." European Journal of Protistology 36, no. 4 (December 2000): 459–64. http://dx.doi.org/10.1016/s0932-4739(00)80052-8.

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47

De La Fuente, Rabindranath. "Chromatin modifications in the germinal vesicle (GV) of mammalian oocytes." Developmental Biology 292, no. 1 (April 2006): 1–12. http://dx.doi.org/10.1016/j.ydbio.2006.01.008.

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48

Grabarek, Joanna B., Berenika Płusa, Jacek A. Modliński, and Jolanta Karasiewicz. "Reconstruction of enucleated mouse germinal vesicle oocytes with blastomere nuclei." Zygote 12, no. 2 (May 2004): 163–72. http://dx.doi.org/10.1017/s0967199404002746.

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We have investigated the possibility that mitotic nuclei originating from preimplantation stage embryos and placed in the oocyte cytoplasm can undergo remodelling that allows them to undergo meiosis in the mouse. To address this question, we have used enucleated germinal vesicle (GV) ooplasts as recipients and blastomeres from the 2-, 4- or 8-cell stage as nuclear donors. We employed two methods to obtain ooplasts from GV oocytes: cutting and enucleation. Although efficiency of the reconstruction process was higher after enucleation than after cutting (90% and 70% respectively), the developmental potential of the oocytes was independent of how they had been produced. Nuclei from the 2-, 4-, or 8-cell stage embryos supported maturation in about 35%, 55% and 60% of cases, respectively. The time between nuclear envelope breakdown and the first meiotic division was shortened by up to 5 h in reconstructed oocytes, a period equivalent to the mitotic division of control blastomeres. About one-third of oocytes reconstituted with blastomere nuclei divided symmetrically instead of extruding a polar body; however, in the majority of them metaphase plates were found, suggesting that reconstructed oocytes (cybrids) underwent a meiotic rather than mitotic division. The highest percentage of asymmetric divisions accompanied by metaphase plates was found in cybrids with 8-cell-stage blastomere nuclei, suggesting that the nuclei from this stage appear to conform best to the cytoplasmic environment of GV ooplasts. Our results indicate that the oocyte cytoplasm is capable of remodelling blastomere nuclei, allowing them to follow the path of the meiotic cell cycle.
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49

Bucci, Stefania, Letizia Giani, Giorgio Mancino, Mario Pellegrino, and Matilde Ragghianti. "TAFII70 protein in Cajal bodies of the amphibian germinal vesicle." Genome 44, no. 6 (December 1, 2001): 1100–1103. http://dx.doi.org/10.1139/g01-111.

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The localization of the TATA-binding protein (TBP) associated factor II70 (TAFII70) in the germinal vesicle (GV) of newt oocytes was investigated. In spreads of GV content, anti-hTAFII70 monoclonal antibody (mAb) stained Cajal bodies (CBs) that were either attached to specific sites on the lampbrush chromosomes or free in the nucleoplasm. To confirm this localization the PwTAFII70 cDNA was cloned and myc-tagged transcripts injected into the oocyte cytoplasm. Newly translated PwTAFII70 protein was detected a few hours later in the Cajal bodies. These data support the hypothesis that Cajal bodies are the assembly sites of the transcription machinery of the oocyte nucleus. TAFII70 protein can play a role in lampbrush transcription; alternatively TAFII70 can be considered a component in the subset of TFIID complexes that do not function during oogenesis, but are accumulated in the oocyte for later use during early development.Key words: TAFII70, Cajal body, lampbrush chromosomes, RNA transcription and processing, newts, Pleurodeles.
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50

Comoglio, F., F. Moffa, H. Liu, J. A. Grifo, L. C. Krey, and J. Zhang. "Germinal Vesicle Transfer Between Fresh and Cryopreserved Immature Mouse Oocytes." Fertility and Sterility 74, no. 3 (September 2000): S47—S48. http://dx.doi.org/10.1016/s0015-0282(00)00847-5.

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