Zeitschriftenartikel: „Dendritic arborization“

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Schaefer, Andreas T., Matthew E. Larkum, Bert Sakmann und Arnd Roth. „Coincidence Detection in Pyramidal Neurons Is Tuned by Their Dendritic Branching Pattern“. Journal of Neurophysiology 89, Nr. 6 (Juni 2003): 3143–54. http://dx.doi.org/10.1152/jn.00046.2003.

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Neurons display a variety of complex dendritic morphologies even within the same class. We examined the relationship between dendritic arborization and the coupling between somatic and dendritic action potential (AP) initiation sites in layer 5 (L5) neocortical pyramidal neurons. Coupling was defined as the relative reduction in threshold for initiation of a dendritic calcium AP due to a coincident back-propagating AP. Simulations based on reconstructions of biocytin-filled cells showed that addition of oblique branches of the main apical dendrite in close proximity to the soma ( d < 140 μm) increases the coupling between the apical and axosomatic AP initiation zones, whereas incorporation of distal branches decreases coupling. Experimental studies on L5 pyramids in acute brain slices revealed a highly significant ( n = 28, r = 0.63, P < 0.0005) correlation: increasing the fraction of proximal oblique dendrites ( d < 140 μm), e.g., from 30 to 60% resulted on average in an increase of the coupling from approximately 35% to almost 60%. We conclude that variation in dendritic arborization may be a key determinant of variability in coupling (49 ± 17%; range 19–83%; n = 37) and is likely to outweigh the contribution made by variations in active membrane properties. Thus coincidence detection of inputs arriving from different cortical layers is strongly regulated by differences in dendritic arborization.

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Chen, Chiung-Ya, Chia-Wen Lin, Chiung-Ying Chang, Si-Tse Jiang und Yi-Ping Hsueh. „Sarm1, a negative regulator of innate immunity, interacts with syndecan-2 and regulates neuronal morphology“. Journal of Cell Biology 193, Nr. 4 (09.05.2011): 769–84. http://dx.doi.org/10.1083/jcb.201008050.

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Dendritic arborization is a critical neuronal differentiation process. Here, we demonstrate that syndecan-2 (Sdc2), a synaptic heparan sulfate proteoglycan that triggers dendritic filopodia and spine formation, regulates dendritic arborization in cultured hippocampal neurons. This process is controlled by sterile α and TIR motif–containing 1 protein (Sarm1), a negative regulator of Toll-like receptor 3 (TLR3) in innate immunity signaling. We show that Sarm1 interacts with and receives signal from Sdc2 and controls dendritic arborization through the MKK4–JNK pathway. In Sarm1 knockdown mice, dendritic arbors of neurons were less complex than those of wild-type littermates. In addition to acting downstream of Sdc2, Sarm1 is expressed earlier than Sdc2, which suggests that it has multiple roles in neuronal morphogenesis. Specifically, it is required for proper initiation and elongation of dendrites, axonal outgrowth, and neuronal polarization. These functions likely involve Sarm1-mediated regulation of microtubule stability, as Sarm1 influenced tubulin acetylation. This study thus reveals the molecular mechanism underlying the action of Sarm1 in neuronal morphogenesis.

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Mishra, Archana, Boris Knerr, Sónia Paixão, Edgar R. Kramer und Rüdiger Klein. „The Protein Dendrite Arborization and Synapse Maturation 1 (Dasm-1) Is Dispensable for Dendrite Arborization“. Molecular and Cellular Biology 28, Nr. 8 (11.02.2008): 2782–91. http://dx.doi.org/10.1128/mcb.02102-07.

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ABSTRACT The development of a highly branched dendritic tree is essential for the establishment of functional neuronal connections. The evolutionarily conserved immunoglobulin superfamily member, the protein dendrite arborization and synapse maturation 1 (Dasm-1) is thought to play a critical role in dendrite formation of dissociated hippocampal neurons. RNA interference-mediated Dasm-1 knockdown was previously shown to impair dendrite, but not axonal, outgrowth and branching (S. H. Shi, D. N. Cox, D. Wang, L. Y. Jan, and Y. N. Jan, Proc. Natl. Acad. Sci. USA 101:13341-13345, 2004). Here, we report the generation and analysis of Dasm-1 null mice. We find that genetic ablation of Dasm-1 does not interfere with hippocampal dendrite growth and branching in vitro and in vivo. Moreover, the absence of Dasm-1 does not affect the modulation of dendritic outgrowth induced by brain-derived neurotrophic factor. Importantly, the previously observed impairment in dendrite growth after Dasm-1 knockdown is also observed when the Dasm-1 knockdown is performed in cultured hippocampal neurons from Dasm-1 null mice. These findings indicate that the dendrite arborization phenotype was caused by off-target effects and that Dasm-1 is dispensable for hippocampal dendrite arborization.

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Fujishima, Kazuto, Junko Kurisu, Midori Yamada und Mineko Kengaku. „βIII spectrin controls the planarity of Purkinje cell dendrites by modulating perpendicular axon-dendrite interactions“. Development 147, Nr. 24 (24.11.2020): dev194530. http://dx.doi.org/10.1242/dev.194530.

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ABSTRACTThe mechanism underlying the geometrical patterning of axon and dendrite wiring remains elusive, despite its crucial importance in the formation of functional neural circuits. The cerebellar Purkinje cell (PC) arborizes a typical planar dendrite, which forms an orthogonal network with granule cell (GC) axons. By using electrospun nanofiber substrates, we reproduce the perpendicular contacts between PC dendrites and GC axons in culture. In the model system, PC dendrites show a preference to grow perpendicularly to aligned GC axons, which presumably contribute to the planar dendrite arborization in vivo. We show that βIII spectrin, a causal protein for spinocerebellar ataxia type 5, is required for the biased growth of dendrites. βIII spectrin deficiency causes actin mislocalization and excessive microtubule invasion in dendritic protrusions, resulting in abnormally oriented branch formation. Furthermore, disease-associated mutations affect the ability of βIII spectrin to control dendrite orientation. These data indicate that βIII spectrin organizes the mouse dendritic cytoskeleton and thereby regulates the oriented growth of dendrites with respect to the afferent axons.

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Troilo, David, Meijuan Xiong, Justin C. Crowley und Barbara L. Finlay. „Factors controlling the dendritic arborization of retinal ganglion cells“. Visual Neuroscience 13, Nr. 4 (Juli 1996): 721–33. http://dx.doi.org/10.1017/s0952523800008609.

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AbstractThe effects of changing retinal ganglion cell (RGC) density and availability of presynaptic sites on the development of RGC dendritic arbor in the developing chick retina were contrasted. Visual form deprivation was used to induce ocular enlargement and expanded retinal area resulting in a 20–30% decrease in RGC density. In these retinas, RGC dendritic arbors increased in a compensatory manner to maintain the inner nuclear layer to RGC convergence ratio in a way that is consistent with simple stretching; RGC dendritic arbors become larger with increased branch lengths, but without change in the total number of branches. In the second manipulation, partial optic nerve section was used to produce areas of RGC depletion of approximately 60% in the central retina. This reduction in density is comparable to the density of locations in the normal peripheral retina. In RGC-depleted retinas, dendritic arbor areas of RGCs in the central retina grow to match the size of normal peripheral arbors. In contrast to the expanded case, two measures of intrinsic arbor structure are changed in RGC-depleted retinas; the branch density of RGC dendrites is greater, and the relative areas of the two arbors of bistratified cells are altered. We discuss the potential roles of retinal growth, local RGC density, and availability of presynaptic terminals in the developmental control of RGC dendritic arbor.

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Jan, Yuh-Nung, und Lily Yeh Jan. „Branching out: mechanisms of dendritic arborization“. Nature Reviews Neuroscience 11, Nr. 5 (Mai 2010): 316–28. http://dx.doi.org/10.1038/nrn2836.

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Kong, Jiming, Vivian W. Y. Tung, John Aghajanian und Zuoshang Xu. „Antagonistic Roles of Neurofilament Subunits NF-H and NF-M Against NF-L in Shaping Dendritic Arborization in Spinal Motor Neurons“. Journal of Cell Biology 140, Nr. 5 (09.03.1998): 1167–76. http://dx.doi.org/10.1083/jcb.140.5.1167.

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Dendrites play important roles in neuronal function. However, the cellular mechanism for the growth and maintenance of dendritic arborization is unclear. Neurofilaments (NFs), a major component of the neuronal cytoskeleton, are composed of three polypeptide subunits, NF-H, NF-M, and NF-L, and are abundant in large dendritic trees. By overexpressing each of the three NF subunits in transgenic mice, we altered subunit composition and found that increasing NF-H and/or NF-M inhibited dendritic arborization, whereas increasing NF-L alleviated this inhibition. Examination of cytoskeletal organization revealed that increasing NF-H and/or NF-M caused NF aggregation and dissociation of the NF network from the microtubule (MT) network. Increasing NF-H or NF-H together with NF-M further reduced NFs from dendrites. However, these changes were reversed by elevating the level of NF-L with either NF-H or NF-M. Thus, NF-L antagonizes NF-H and NF-M in organizing the NF network and maintaining a lower ratio of NF-H and NF-M to NF-L is critical for the growth of complex dendritic trees in motor neurons.

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Keil, Kimberly P., Sunjay Sethi und Pamela J. Lein. „Sex-Dependent Effects of 2,2′,3,5′,6-Pentachlorobiphenyl on Dendritic Arborization of Primary Mouse Neurons“. Toxicological Sciences 168, Nr. 1 (03.11.2018): 95–109. http://dx.doi.org/10.1093/toxsci/kfy277.

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AbstractEarly life exposures to environmental contaminants are implicated in the pathogenesis of many neurodevelopmental disorders (NDDs). These disorders often display sex biases, but whether environmental neurotoxicants act in a sex-dependent manner to modify neurodevelopment is largely unknown. Since altered dendritic morphology is associated with many NDDs, we tested the hypothesis that male and female primary mouse neurons are differentially susceptible to the dendrite-promoting activity of 2,2′,3,5′,6-pentachlorobiphenyl (PCB 95). Hippocampal and cortical neuron-glia co-cultures were exposed to vehicle (0.1% dimethylsulfoxide) or PCB 95 (100 fM–1 μM) from day in vitro 7–9. As determined by Sholl analysis, PCB 95-enhanced dendritic growth in female but not male hippocampal and cortical neurons. In contrast, both male and female neurons responded to bicuculline with increased dendritic complexity. Detailed morphometric analyses confirmed that PCB 95 effects on the number and length of primary and nonprimary dendrites varied depending on sex, brain region and PCB concentration, and that female neurons responded more consistently with increased dendritic growth and at lower concentrations of PCB 95 than their male counterparts. Exposure to PCB 95 did not alter cell viability or the ratio of neurons to glia in cultures of either sex. These results demonstrate that cultured female mouse hippocampal and cortical neurons are more sensitive than male neurons to the dendrite-promoting activity of PCB 95, and suggest that mechanisms underlying PCB 95-induced dendritic growth are sex-dependent. These data highlight the importance of sex in neuronal responses to environmental neurotoxicants.

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Keeler, Austin B., Dietmar Schreiner und Joshua A. Weiner. „Protein Kinase C Phosphorylation of a γ-Protocadherin C-terminal Lipid Binding Domain Regulates Focal Adhesion Kinase Inhibition and Dendrite Arborization“. Journal of Biological Chemistry 290, Nr. 34 (02.07.2015): 20674–86. http://dx.doi.org/10.1074/jbc.m115.642306.

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The γ-protocadherins (γ-Pcdhs) are a family of 22 adhesion molecules with multiple critical developmental functions, including the proper formation of dendritic arbors by forebrain neurons. The γ-Pcdhs bind to and inhibit focal adhesion kinase (FAK) via a constant C-terminal cytoplasmic domain shared by all 22 proteins. In cortical neurons lacking the γ-Pcdhs, aberrantly high activity of FAK and of PKC disrupts dendrite arborization. Little is known, however, about how γ-Pcdh function is regulated by other factors. Here we show that PKC phosphorylates a serine residue situated within a phospholipid binding motif at the shared γ-Pcdh C terminus. Western blots using a novel phospho-specific antibody against this site suggest that a portion of γ-Pcdh proteins is phosphorylated in the cortex in vivo. We find that PKC phosphorylation disrupts both phospholipid binding and the γ-Pcdh inhibition of (but not binding to) FAK. Introduction of a non-phosphorylatable (S922A) γ-Pcdh construct into wild-type cortical neurons significantly increases dendrite arborization. This same S922A construct can also rescue dendrite arborization defects in γ-Pcdh null neurons cell autonomously. Consistent with these data, introduction of a phosphomimetic (S/D) γ-Pcdh construct or treatment with a PKC activator reduces dendrite arborization in wild-type cortical neurons. Together, these data identify a novel mechanism through which γ-Pcdh control of a signaling pathway important for dendrite arborization is regulated.

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SCHIERWAGEN, ANDREAS K., und JAAP VAN PELT. „SHAPING NEURONAL DENDRITES: INTERPLAY OF TOPOLOGICAL AND METRICAL PARAMETERS“. Journal of Biological Systems 03, Nr. 04 (Dezember 1995): 1193–200. http://dx.doi.org/10.1142/s0218339095001076.

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The functional role of a neuron within a network is influenced by the geometry of its dendrites. In the present study we have used a new model of dendritic arborization to analyze how metrical and topological parameters interact to shape a certain dendritic tree. One of the specific questions addressed is how to change topological variability in a systematic way while preserving the metrical features. The second problem concerns the effect of topology on the relationship between dendritic size and the distribution of dendritic surface area with radial distance from soma. The simulation results reproduce features of dendritic architecture found in neocortical pyramidal cells and cat superior colliculus neurons.

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Grueber, Wesley B., Lily Y. Jan und Yuh Nung Jan. „Tiling of the Drosophila epidermis by multidendritic sensory neurons“. Development 129, Nr. 12 (15.06.2002): 2867–78. http://dx.doi.org/10.1242/dev.129.12.2867.

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Insect dendritic arborization (da) neurons provide an opportunity to examine how diverse dendrite morphologies and dendritic territories are established during development. We have examined the morphologies of Drosophila da neurons by using the MARCM (mosaic analysis with a repressible cell marker) system. We show that each of the 15 neurons per abdominal hemisegment spread dendrites to characteristic regions of the epidermis. We place these neurons into four distinct morphological classes distinguished primarily by their dendrite branching complexities. Some class assignments correlate with known proneural gene requirements as well as with central axonal projections. Our data indicate that cells within two morphological classes partition the body wall into distinct, non-overlapping territorial domains and thus are organized as separate tiled sensory systems. The dendritic domains of cells in different classes, by contrast, can overlap extensively. We have examined the cell-autonomous roles of starry night (stan) (also known as flamingo (fmi)) and sequoia (seq) in tiling. Neurons with these genes mutated generally terminate their dendritic fields at normal locations at the lateral margin and segment border, where they meet or approach the like dendrites of adjacent neurons. However, stan mutant neurons occasionally send sparsely branched processes beyond these territories that could potentially mix with adjacent like dendrites. Together, our data suggest that widespread tiling of the larval body wall involves interactions between growing dendritic processes and as yet unidentified signals that allow avoidance by like dendrites.

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Jan, Yuh-Nung, und Lily Yeh Jan. „Erratum: Branching out: mechanisms of dendritic arborization“. Nature Reviews Neuroscience 11, Nr. 6 (Juni 2010): 449. http://dx.doi.org/10.1038/nrn2854.

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Xiao, Lan. „Different Influences of Lipofection and Electrotransfection on In Vitro Gene Delivery to Primary Cultured Cortex Neurons“. March 2016 3;19, Nr. 3;3 (14.03.2016): 189–96. http://dx.doi.org/10.36076/ppj/2019.19.189.

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Background: Many pain states are linked to central nervous system (CNS) diseases involving the dysfunction of dendritic arborization, making restoration a promising therapeutic strategy. Transfection of primary cortex neurons offers the possibility to study mechanisms which are important for the restoration of proper arborization. Its progress is, however, limited at present due to the lack of suitable gene transfer techniques. Objective: To obtain better insight into the transfection potential of currently used techniques, 2 non-viral transfection methods, lipofection and gene electrotransfer (GET), were compared. Study Design: This is a comparison study performed on cultured cells. Methods: The transfection efficiency and neuronal viability, as well as the neuronal dendritic arborization after lipofection or GET, were compared. Primary cultured cortex neurons were transfected with the pEGFP-N1 plasmid, either using Lipofectamine 2000 (2, 3, or 4μL) or with electroporation, with our previously optimized protocol (200V/25 ms). Results: Transfection efficiency and cell viability were inversely proportional for lipofection. The appropriate ratio of Lipofectamine and plasmid DNA provides optimal conditions for lipofection. Although GET offered higher transfection efficiency, it could not induce complex dendritic arborization, which made it unsuitable for in vitro gene transfer into cortex neurons. Limitations: Limitations include species variability and translational applicability for CNS diseases and pain states related to potential toxicity. Conclusions: Based on these findings, lipofection might be advantageous for in vitro application to primary cultured cortex neurons. Pain states, stress mediated pathogenesis, and certain CNS diseases might potentially utilize this important technique in the future as a therapeutic modality. Key words: Lipofection, gene electrotransfer, CNS diseases, pain states, dendritic arborization, transfection of primary cortex neurons

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Amthor, Franklin R., Norberto M. Grzywacz und David K. Merwine. „Extra-receptive-field motion facilitation in on-off directionally selective ganglion cells of the rabbit retina“. Visual Neuroscience 13, Nr. 2 (März 1996): 303–9. http://dx.doi.org/10.1017/s0952523800007549.

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AbstractThe excitatory receptive-field centers of On-Off directionally selective (DS) ganglioncells of the rabbit retina correspond closely to the lateral extent of their dendritic arborizations. Some investigators have hypothesized from this that theories for directionalselectivity that entail a lateral spread of excitation from outside the ganglion cell dendritic tree, such as from starburst amacrine cells, are therefore untenable. We show herethat significant motion facilitation is conducted from well outside the classical excitatory receptive-field center (and, therefore, dendritic arborization) of On-Off DS ganglioncells for preferred-direction, but not null-direction moving stimuli. These results are consistent with a role in directional selectivity for cells with processes lying beyond the On-Off ganglion cell's excitatory receptive-field center. These results also highlight the fundamental distinction in retinal ganglion cell receptive-field organization between classical excitatory mechanisms and those that facilitate other excitation without producing directly observable excitation by themselves.

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Alizzi, Rebecca A., Derek Xu, Conrad M. Tenenbaum, Wei Wang und Elizabeth R. Gavis. „The ELAV/Hu protein Found in neurons regulates cytoskeletal and ECM adhesion inputs for space-filling dendrite growth“. PLOS Genetics 16, Nr. 12 (28.12.2020): e1009235. http://dx.doi.org/10.1371/journal.pgen.1009235.

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Dendritic arbor morphology influences how neurons receive and integrate extracellular signals. We show that the ELAV/Hu family RNA-binding protein Found in neurons (Fne) is required for space-filling dendrite growth to generate highly branched arbors of Drosophila larval class IV dendritic arborization neurons. Dendrites of fne mutant neurons are shorter and more dynamic than in wild-type, leading to decreased arbor coverage. These defects result from both a decrease in stable microtubules and loss of dendrite-substrate interactions within the arbor. Identification of transcripts encoding cytoskeletal regulators and cell-cell and cell-ECM interacting proteins as Fne targets using TRIBE further supports these results. Analysis of one target, encoding the cell adhesion protein Basigin, indicates that the cytoskeletal defects contributing to branch instability in fne mutant neurons are due in part to decreased Basigin expression. The ability of Fne to coordinately regulate the cytoskeleton and dendrite-substrate interactions in neurons may shed light on the behavior of cancer cells ectopically expressing ELAV/Hu proteins.

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Li, Haimin, Gang Chen, Bing Zhou und Shumin Duan. „Actin Filament Assembly by Myristoylated, Alanine-rich C Kinase Substrate–Phosphatidylinositol-4,5-diphosphate Signaling Is Critical for Dendrite Branching“. Molecular Biology of the Cell 19, Nr. 11 (November 2008): 4804–13. http://dx.doi.org/10.1091/mbc.e08-03-0294.

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Dendrites undergo extensive growth and branching at early stages, but relatively little is known about the molecular mechanisms underlying these processes. Here, we show that increasing the level of myristoylated, alanine-rich C kinase substrate (MARCKS), a prominent substrate of protein kinase C and a phosphatidylinositol-4,5-diphosphate [PI(4,5)P2] sequestration protein highly expressed in the brain, enhanced branching and growth of dendrites both in vitro and in vivo. Conversely, knockdown of endogenous MARCKS by RNA interference reduced dendritic arborization. Results from expression of different mutants indicated that membrane binding is essential for MARCKS-induced dendritic morphogenesis. Furthermore, MARCKS increased the number and length of filamentous actin-based filopodia along neurites, as well as the motility of filopodia, in a PI(4,5)P2-dependent manner. Time-lapse imaging showed that MARCKS increased frequency of filopodia initiation but did not affect filopodia longevity, suggesting that MARCKS may increase dendritic branching through its action on filopodia initiation. These findings demonstrate a critical role for MARCKS–PI(4,5)P2 signaling in regulating dendrite development.

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Tsuyama, Taiichi, Asako Tsubouchi, Tadao Usui, Hiromi Imamura und Tadashi Uemura. „Mitochondrial dysfunction induces dendritic loss via eIF2α phosphorylation“. Journal of Cell Biology 216, Nr. 3 (16.02.2017): 815–34. http://dx.doi.org/10.1083/jcb.201604065.

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Mitochondria are key contributors to the etiology of diseases associated with neuromuscular defects or neurodegeneration. How changes in cellular metabolism specifically impact neuronal intracellular processes and cause neuropathological events is still unclear. We here dissect the molecular mechanism by which mitochondrial dysfunction induced by Prel aberrant function mediates selective dendritic loss in Drosophila melanogaster class IV dendritic arborization neurons. Using in vivo ATP imaging, we found that neuronal cellular ATP levels during development are not correlated with the progression of dendritic loss. We searched for mitochondrial stress signaling pathways that induce dendritic loss and found that mitochondrial dysfunction is associated with increased eIF2α phosphorylation, which is sufficient to induce dendritic pathology in class IV arborization neurons. We also observed that eIF2α phosphorylation mediates dendritic loss when mitochondrial dysfunction results from other genetic perturbations. Furthermore, mitochondrial dysfunction induces translation repression in class IV neurons in an eIF2α phosphorylation-dependent manner, suggesting that differential translation attenuation among neuron subtypes is a determinant of preferential vulnerability.

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Narayanan, Rishikesh, Anusha Narayan und Sumantra Chattarji. „A Probabilistic Framework for Region-Specific Remodeling of Dendrites in Three-Dimensional Neuronal Reconstructions“. Neural Computation 17, Nr. 1 (01.01.2005): 75–96. http://dx.doi.org/10.1162/0899766052530811.

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Dendritic arborization is an important determinant of single-neuron function as well as the circuitry among neurons. Dendritic trees undergo remodeling during development, aging, and many pathological conditions, with many of the morphological changes being confined to certain regions of the dendritic tree. In order to analyze the functional consequences of such region-specific dendritic remodeling, it is essential to develop techniques that can systematically manipulate three-dimensional reconstructions of neurons. Hence, in this study, we develop an algorithm that uses statistics from precise morphometric analyses to systematically remodel neuronal reconstructions. We use the distribution function of the ratio of two normal distributed random variables to specify the probabilities of remodeling along various regions of the dendritic arborization. We then use these probabilities to drive an iterative algorithm for manipulating the dendritic tree in a region-specific manner. As a test, we apply this framework to a well-characterized example of dendritic remodeling: stress-induced dendritic atrophy in hippocampal CA3 pyramidal cells. We show that our pruning algorithm is capable of eliciting atrophy that matches biological data from rodent models of chronic stress.

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Yong, Hyo-Jeong, Jong-Ik Hwang und Jae-Young Seong. „Alterations in Dendritic Spine Maturation and Neurite Development Mediated by FAM19A1“. Cells 10, Nr. 8 (23.07.2021): 1868. http://dx.doi.org/10.3390/cells10081868.

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Neurogenesis and functional brain activity require complex associations of inherently programmed secretory elements that are regulated precisely and temporally. Family with sequence similarity 19 A1 (FAM19A1) is a secreted protein primarily expressed in subsets of terminally differentiated neuronal precursor cells and fully mature neurons in specific brain substructures. Several recent studies have demonstrated the importance of FAM19A1 in brain physiology; however, additional information is needed to support its role in neuronal maturation and function. In this study, dendritic spine morphology in Fam19a1-ablated mice and neurite development during in vitro neurogenesis were examined to understand the putative role of FAM19A1 in neural integrity. Adult Fam19a1-deficient mice showed low dendritic spine density and maturity with reduced dendrite complexity compared to wild-type (WT) littermates. To further explore the effect of FAM19A1 on neuronal maturation, the neurite outgrowth pattern in primary neurons was analyzed in vitro with and without FAM19A1. In response to FAM19A1, WT primary neurons showed reduced neurite complexity, whereas Fam19a1-decifient primary neurons exhibited increased neurite arborization, which was reversed by supplementation with recombinant FAM19A1. Together, these findings suggest that FAM19A1 participates in dendritic spine development and neurite arborization.

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Watanabe, Kaori, Yuki Furumizo, Tadao Usui, Yukako Hattori und Tadashi Uemura. „Nutrient-dependent increased dendritic arborization of somatosensory neurons“. Genes to Cells 22, Nr. 1 (21.11.2016): 105–14. http://dx.doi.org/10.1111/gtc.12451.

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Milošević, Nebojša T., und Dušan Ristanović. „Fractality of dendritic arborization of spinal cord neurons“. Neuroscience Letters 396, Nr. 3 (April 2006): 172–76. http://dx.doi.org/10.1016/j.neulet.2005.11.031.

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Czöndör, Katalin, Kornelia Ellwanger, Yannick F. Fuchs, Sylke Lutz, Márton Gulyás, Isabelle M. Mansuy, Angelika Hausser, Klaus Pfizenmaier und Katalin Schlett. „Protein Kinase D Controls the Integrity of Golgi Apparatus and the Maintenance of Dendritic Arborization in Hippocampal Neurons“. Molecular Biology of the Cell 20, Nr. 7 (April 2009): 2108–20. http://dx.doi.org/10.1091/mbc.e08-09-0957.

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Protein kinase D (PKD) is known to participate in various cellular functions, including secretory vesicle fission from the Golgi and plasma membrane-directed transport. Here, we report on expression and function of PKD in hippocampal neurons. Expression of an enhanced green fluorescent protein (EGFP)-tagged PKD activity reporter in mouse embryonal hippocampal neurons revealed high endogenous PKD activity at the Golgi complex and in the dendrites, whereas PKD activity was excluded from the axon in parallel with axonal maturation. Expression of fluorescently tagged wild-type PKD1 and constitutively active PKD1S738/742E (caPKD1) in neurons revealed that both proteins were slightly enriched at the trans-Golgi network (TGN) and did not interfere with its thread-like morphology. By contrast, expression of dominant-negative kinase inactive PKD1K612W (kdPKD1) led to the disruption of the neuronal Golgi complex, with kdPKD1 strongly localized to the TGN fragments. Similar findings were obtained from transgenic mice with inducible, neuron-specific expression of kdPKD1-EGFP. As a prominent consequence of kdPKD1 expression, the dendritic tree of transfected neurons was reduced, whereas caPKD1 increased dendritic arborization. Our results thus provide direct evidence that PKD activity is selectively involved in the maintenance of dendritic arborization and Golgi structure of hippocampal neurons.

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Mohandas Rao, K. G., S. Muddanna Rao und S. Gurumadhva Rao. „Enhancement of Amygdaloid Neuronal Dendritic Arborization by Fresh Leaf Juice ofCentella asiatica(Linn) during Growth Spurt Period in Rats“. Evidence-Based Complementary and Alternative Medicine 6, Nr. 2 (2009): 203–10. http://dx.doi.org/10.1093/ecam/nem079.

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Centella asiatica(CeA) is a creeping herb, growing in moist places in India and other Asian Countries. Ayurvedic system of medicine, an alternate system of medicine in India, uses leaves of CeA for memory enhancement. Here, we have investigated the role of CeA fresh leaf juice treatment during growth spurt period of rats on dendritic morphology of amygdaloid neurons, one of the regions concerned with learning and memory. The present study was conducted on neonatal rat pups. The rat pups (7-days-old) were fed with 2, 4 and 6 ml/kg body of fresh leaf juice of CeA for 2, 4 and 6 weeks. After the treatment period, the rats were killed, brains removed and amygdaloid neurons impregnated with Silver nitrate (Golgi staining). Amygdaloid neurons were traced using camera lucida and dendritic branching points (a measure of dendritic arborization) and intersections (a measure dendritic length) quantified. These data were compared with those of age-matched control rats. The results showed a significant increase in dendritic length (intersections) and dendritic branching points along the length of dendrites of the amygdaloid neurons of rats treated with 4 and 6 ml/kg body weight/day of CeA for longer periods of time (i.e. 4 and 6 weeks). We conclude that constituents/active principles present in CeA fresh leaf juice has neuronal dendritic growth stimulating property; hence it can be used for enhancing neuronal dendrites in stress and other neurodegenerative and memory disorders.

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Gan, Kathlyn J., und Thomas C. Südhof. „Specific factors in blood from young but not old mice directly promote synapse formation and NMDA-receptor recruitment“. Proceedings of the National Academy of Sciences 116, Nr. 25 (03.06.2019): 12524–33. http://dx.doi.org/10.1073/pnas.1902672116.

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Aging drives a progressive decline in cognition and decreases synapse numbers and synaptic function in the brain, thereby increasing the risk for neurodegenerative disease. Pioneering studies showed that introduction of blood from young mice into aged mice reversed age-associated cognitive impairments and increased synaptic connectivity in brain, suggesting that young blood contains specific factors that remediate age-associated decreases in brain function. However, whether such factors in blood from young animals act directly on neurons to enhance synaptic connectivity, or whether they act by an indirect mechanism remains unknown. Moreover, which factors in young blood mediate cognitive improvements in old mice is incompletely understood. Here, we show that serum extracted from the blood of young but not old mice, when applied to neurons transdifferentiated from human embryonic stem cells, directly increased dendritic arborization, augmented synapse numbers, doubled dendritic spine-like structures, and elevated synaptic N-methyl-d-aspartate (NMDA) receptors, thereby increasing synaptic connectivity. Mass spectrometry revealed that thrombospondin-4 (THBS4) and SPARC-like protein 1 (SPARCL1) were enriched in serum from young mice. Strikingly, recombinant THBS4 and SPARCL1 both increased dendritic arborization and doubled synapse numbers in cultured neurons. In addition, SPARCL1 but not THBS4 tripled NMDA receptor-mediated synaptic responses. Thus, at least two proteins enriched in young blood, THBS4 and SPARCL1, directly act on neurons as synaptogenic factors. These proteins may represent rejuvenation factors that enhance synaptic connectivity by increasing dendritic arborization, synapse formation, and synaptic transmission.

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Cowan, R. L., und C. J. Wilson. „Spontaneous firing patterns and axonal projections of single corticostriatal neurons in the rat medial agranular cortex“. Journal of Neurophysiology 71, Nr. 1 (01.01.1994): 17–32. http://dx.doi.org/10.1152/jn.1994.71.1.17.

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1. Spontaneous fluctuations of membrane potential, patterns of spontaneous firing, dendritic branching patterns, and intracortical and striatal axonal arborizations were compared for two types of corticostriatal neurons in the medial agranular cortex of urethan-anesthetized rats: 1) pyramidal tract (PT) cells identified by antidromic activation from the medullary pyramid and 2) crossed corticostriatal (CST) neurons identified by antidromic activation from the contralateral neostriatum. The ipsilateral corticostriatal projections of intracellularly stained PT neurons as well as contralateral corticostriatal neurons were confirmed after labeling by intracellular injection of biocytin. 2. All well-stained PT neurons had intracortical and intrastriatal collaterals. The more common type (6 of 8) was a large, deep layer V neuron that had an extensive intracortical axon arborization but a limited axon arborization in the neostriatum. The less common type of PT neuron (2 of 8) was a medium-sized, superficial layer V neuron that had a limited intracortical axon arborization but a larger and more dense intrastriatal axonal arborization. Both subclasses of PT neurons had anatomic and physiological properties associated with slow PT cells in cats and monkeys and conduction velocities < 10 m/s. All of the PT cells but one were regular spiking cells. The exception cell fired intrinsic bursts. 3. Intracellularly stained CST neurons were located in the superficial half of layer V and the deep part of layer III. Their layer I apical dendrites were few and sparsely branched. Their axons gave rise to an extensive arbor of local axon collaterals that distributed in the region of the parent neuron, frequently extending throughout the more superficial layers, including layer I. Axon collaterals were also traced to the corpus callosum, as expected from their contralateral projections, and they contributed axon collaterals to the ipsilateral neostriatum. In the neostriatum, these axons formed extended arborizations sparsely occupying a large volume of striatal tissue. All CST neurons were regular spiking cells. 4. Both types of cells displayed spontaneous membrane fluctuations consisting of a polarized state (-60 to -90 mV) that was interrupted by 0.1- to 3.0-s periods of depolarization (-55 to -45 mV) accompanied by action potentials. The membrane potential was relatively constant in each state, and transitions between the depolarized and hyperpolarized states were sometimes periodic with a frequency of 0.3–1.5 Hz. A much faster (30-45 Hz) subthreshold oscillation of the membrane potential was observed only in the depolarized state and triggered action potentials that locked to the depolarizing peaks of this rhythm.(ABSTRACT TRUNCATED AT 400 WORDS)

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Mohandas Rao, K. G., S. Muddanna Rao und S. Gurumadhva Rao. „Centella asiatica (L.) Leaf Extract Treatment During the Growth Spurt Period Enhances Hippocampal CA3 Neuronal Dendritic Arborization in Rats“. Evidence-Based Complementary and Alternative Medicine 3, Nr. 3 (2006): 349–57. http://dx.doi.org/10.1093/ecam/nel024.

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Centella asiatica(CeA) is a creeping plant growing in damp places in India and other Asian countries. The leaves of CeA are used for memory enhancement in the Ayurvedic system of medicine, an alternative system of medicine in India. In this study, we have investigated the effect during the rat growth spurt period of CeA fresh leaf extract treatment on the dendritic morphology of hippocampal CA3 neurons, one of the regions of the brain concerned with learning and memory. Neonatal rat pups (7 days old) were fed with 2, 4 or 6 ml kg−1 body weight of fresh leaf extract of CeA for 2, 4 or 6 weeks. After the treatment period the rats were killed, their brains were removed and the hippocampal neurons were impregnated with silver nitrate (Golgi staining). Hippocampal CA3 neurons were traced using a camera lucida, and dendritic branching points (a measure of dendritic arborization) and intersections (a measure of dendritic length) were quantified. These data were compared with data for age-matched control rats. The results showed a significant increase in the dendritic length (intersections) and dendritic branching points along the length of both apical and basal dendrites in rats treated with 4 and 6 ml kg−1 body weight per day of CeA for longer periods of time (i.e. 4 and 6 weeks). We conclude that the constituents/active principles present in CeA fresh leaf extract have a neuronal dendritic growth stimulating property; hence, the extract can be used for enhancing neuronal dendrites in stress and neurodegenerative and memory disorders.

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MANGRUM, WELLS I., JOHN E. DOWLING und ETHAN D. COHEN. „A morphological classification of ganglion cells in the zebrafish retina“. Visual Neuroscience 19, Nr. 6 (November 2002): 767–79. http://dx.doi.org/10.1017/s0952523802196076.

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We examined the distribution and morphological types of ganglion cells in the retina of the zebrafish, a model vertebrate genetic organism. Using cresyl violet and methylene blue staining, a prominent central area was observed in the ventral temporal retina. The density of ganglion cell layer neurons averaged from ∼12,000/mm2 in the dorsal-nasal retina to a peak of ∼37,000/mm2 in the ventral-temporal retina. Individual zebrafish ganglion cells were labeled by backfilling with DiI through the optic nerve followed by reconstruction using confocal microscopy. The dendritic stratification and branching pattern of each labeled ganglion cell was examined in relation to the borders of the inner plexiform layer (IPL). We identified 11 different morphological types of ganglion cell. The most commonly labeled ganglion cells were two types termed Type III or IV, which displayed highly stratified dendritic arborizations in their respective ON-, OFF-sublaminae of the IPL. Their dendritic branching patterns were highly asymmetric with many thorn-like varicosities that profusely filled the area of arborization. In contrast, Type V cells formed a small simply branching dendritic field in the innermost portion of the ON-sublamina of the IPL. Two large ganglion cell types (Types I and II) with wide monostratified dendritic fields were found in both the ON- and OFF-sublamina of the IPL. Three different types of multistratified/bistratified ganglion cells were found (Types, IX, X, and XI.) whose dendrites occupied different regions of the IPL. The multistratified dendrites of IX cells occupied the whole width of the IPL, while the dendrites of Type XI cells formed vertical claw-like endings in only the ON-sublamina of the IPL. We conclude that zebrafish ganglion cells display a rich variety of types and branching patterns. This study establishes a series of baseline measurements of zebrafish ganglion cells to facilitate examination of genes playing a role in the specification and stratification of ganglion cell types.

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P., Devi N., und J. K. Mukkadan. „EFFECT OF ROTATORY VESTIBULAR STIMULATION ON LEARNING AND MEMORY IN RATS-STANDARDIZATION OF A NOVEL METHOD“. International Journal of Pharmacy and Pharmaceutical Sciences 9, Nr. 1 (31.12.2016): 145. http://dx.doi.org/10.22159/ijpps.2017v9i1.14940.

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Objective: To find out the effect of rotatory vestibular stimulation in cognition in rats through examining the behavioural patterns, the alterations in dendritic arborization and changes in AChE activity.Methods: Rotatory vestibular stimulation was provided in a rotatory vestibular apparatus at a rate of 50 rpm for 5 min, for 30 d for rats. 0.3 mg/kg of physostigmine also administered to rats of another group as a standard drug. No rotatory vestibular stimulation or physostigmine is provided to the control rats. Behavioural analysis, Neuromorphological and biochemical studies were done after vestibular stimulation.Results: No. of trails for acquisition and retention reduced significantly in treated rats when compared with the control rats. In all the treated rats the dendritic arborization increased significantly, and activity of AChE decreased significantly when compare with the control.Conclusion: Rotatory vestibular stimulation enhances learning and memory via increasing dendritic arborization and inhibiting acetyl-cholinesterase activity in rats.

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Avery, Adam W., David D. Thomas und Thomas S. Hays. „β-III-spectrin spinocerebellar ataxia type 5 mutation reveals a dominant cytoskeletal mechanism that underlies dendritic arborization“. Proceedings of the National Academy of Sciences 114, Nr. 44 (16.10.2017): E9376—E9385. http://dx.doi.org/10.1073/pnas.1707108114.

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A spinocerebellar ataxia type 5 (SCA5) L253P mutation in the actin-binding domain (ABD) of β-III-spectrin causes high-affinity actin binding and decreased thermal stability in vitro. Here we show in mammalian cells, at physiological temperature, that the mutant ABD retains high-affinity actin binding. Significantly, we provide evidence that the mutation alters the mobility and recruitment of β-III-spectrin in mammalian cells, pointing to a potential disease mechanism. To explore this mechanism, we developed a Drosophila SCA5 model in which an equivalent mutant Drosophila β-spectrin is expressed in neurons that extend complex dendritic arbors, such as Purkinje cells, targeted in SCA5 pathogenesis. The mutation causes a proximal shift in arborization coincident with decreased β-spectrin localization in distal dendrites. We show that SCA5 β-spectrin dominantly mislocalizes α-spectrin and ankyrin-2, components of the endogenous spectrin cytoskeleton. Our data suggest that high-affinity actin binding by SCA5 β-spectrin interferes with spectrin-actin cytoskeleton dynamics, leading to a loss of a cytoskeletal mechanism in distal dendrites required for dendrite stabilization and arbor outgrowth.

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Schwartz, P. M., R. L. Levy, P. R. Borghesani und R. A. Segal. „Purkinje cell dendritic arborization is defective in BDNF −/− mice“. Molecular Psychiatry 3, Nr. 2 (März 1998): 119–20. http://dx.doi.org/10.1038/sj.mp.4000367.

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Shrestha, Brikha R., und Wesley B. Grueber. „Neuronal Morphogenesis: Worms Get an EFF in Dendritic Arborization“. Current Biology 20, Nr. 16 (August 2010): R673—R675. http://dx.doi.org/10.1016/j.cub.2010.06.053.

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Khaleel, Nagarchi, Ravindranath Roopa, Jangama S. M. Smitha und Chittaranjan Andrade. „Electroconvulsive Therapy Attenuates Dendritic Arborization in the Basolateral Amygdala“. Journal of ECT 29, Nr. 3 (September 2013): 156–57. http://dx.doi.org/10.1097/yct.0b013e318282a6b1.

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Nanda, Sumit, Ravi Das, Shatabdi Bhattacharjee, Daniel N. Cox und Giorgio A. Ascoli. „Morphological determinants of dendritic arborization neurons in Drosophila larva“. Brain Structure and Function 223, Nr. 3 (01.11.2017): 1107–20. http://dx.doi.org/10.1007/s00429-017-1541-9.

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Machamer, James B., Brian M. Woolums, Gregory G. Fuller und Thomas E. Lloyd. „FUS causes synaptic hyperexcitability in Drosophila dendritic arborization neurons“. Brain Research 1693 (August 2018): 55–66. http://dx.doi.org/10.1016/j.brainres.2018.03.037.

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Louis, Elan D., Michelle Lee, Rachel Babij, Karen Ma, Etty Cortés, Jean-Paul G. Vonsattel und Phyllis L. Faust. „Reduced Purkinje cell dendritic arborization and loss of dendritic spines in essential tremor“. Brain 137, Nr. 12 (03.11.2014): 3142–48. http://dx.doi.org/10.1093/brain/awu314.

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Perng, Vivian, Chong Li, Shya Navazesh, Carolyn Klocke, Danna Pinneles, Pamela Lein und Peng Ji. „Iron Deficiency and Iron Excess Alter Dendritic Architecture of Pyramidal Neurons in the Hippocampus of Neonatal Pigs“. Current Developments in Nutrition 4, Supplement_2 (29.05.2020): 1232. http://dx.doi.org/10.1093/cdn/nzaa057_048.

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Abstract Objectives The study assessed effect of dietary iron on iron homeostasis and dendritic architecture of hippocampal neurons in young piglets. Methods On postnatal day (PD) 1, 30 piglets (15 male/female) were blocked by sex and randomized to treatments by receiving no (N), low (L) or high (H) dose of iron supplement during pre- (PD1–21) and post-weaning period (PD22–35). Pigs in N, L, and H group orally received 0, 1, and 30 mg iron/(kg BW· d) as ferrous sulfate solution pre-weaning and were fed a solid diet containing 30, 125, and 1000 mg iron/kg post-weaning, respectively. Blood samples were collected on PD1 and weekly thereafter to analyze iron biomarkers. Iron homeostasis in hippocampus was assessed by measuring gene and protein expression of iron transporters. Hippocampal neurons stained with Golgi-Cox method were traced and 3D reconstructed using Neurolucida. Dendritic arborization were quantified through Sholl analysis and Neurolucida Explorer. Results Pigs in H group had the highest growth rate, whereas N pigs displayed growth retardation from PD27 to PD35, resulting in significant difference in body weight compared to H group (P < 0.05). Iron dose-dependently increased hemoglobin (Hb), hematocrit, plasma iron and transferrin saturation since PD7 or PD14 (P < 0.05). Pigs in N group became iron deficient since PD14 (Hb < 11 g/dL). Similarly, hippocampal ferritin expression was upregulated with the increase of iron (P < 0.05). The mRNA expression of TFRC and DMT1 in hippocampus was highest in N and lowest in H group (P < 0.05). Despite relatively low abundance, HAMP expression tended to be higher in H than that in N (P < 0.10). Sholl analysis uncovered significant main effect of treatment on basilar dendritic arborization of CA1 and CA3 pyramidal neurons (P ≤ 0.04). There were less branching nodes and dendrites in N than in H group (P < 0.05). However, the difference in dendritic arborization was primarily derived from the higher order (> 3) of branches in both regions. Iron supplementation did not affect architecture of apical dendrites of granule cells in dentate gyrus. Conclusions Early-life iron status affects hippocampal iron homeostasis and alters development of pyramidal neurons in a piglet model. Funding Sources NIFA Hatch/Multistate Research Fund.

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Yang, Wei-Kang, und Cheng-Ting Chien. „Beyond being innervated: the epidermis actively shapes sensory dendritic patterning“. Open Biology 9, Nr. 3 (März 2019): 180257. http://dx.doi.org/10.1098/rsob.180257.

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Sensing environmental cues requires well-built neuronal circuits linked to the body surface. Sensory neurons generate dendrites to innervate surface epithelium, thereby making it the largest sensory organ in the body. Previous studies have illustrated that neuronal type, physiological function and branching patterns are determined by intrinsic factors. Perhaps for effective sensation or protection, sensory dendrites bind to or are surrounded by the substrate epidermis. Recent studies have shed light on the mechanisms by which dendrites interact with their substrates. These interactions suggest that substrates can regulate dendrite guidance, arborization and degeneration. In this review, we focus on recent studies of Drosophila and Caenorhabditis elegans that demonstrate how epidermal cells can regulate dendrites in several aspects.

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Urrego, Diana, Julieta Troncoso und Alejandro Múnera. „Layer 5 Pyramidal Neurons’ Dendritic Remodeling and Increased Microglial Density in Primary Motor Cortex in a Murine Model of Facial Paralysis“. BioMed Research International 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/482023.

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This work was aimed at characterizing structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with microglial density induced by facial nerve lesion using a murine facial paralysis model. Adult transgenic mice, expressing green fluorescent protein in microglia and yellow fluorescent protein in projecting neurons, were submitted to either unilateral section of the facial nerve or sham surgery. Injured animals were sacrificed either 1 or 3weeks after surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1). It was found that facial nerve lesion induced long-lasting changes in the dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Dendritic arborization of the pyramidal cells underwent overall shrinkage. Apical dendrites suffered transient shortening while basal dendrites displayed sustained shortening. Moreover, dendrites suffered transient spine pruning. Significantly higher microglial cell density was found surrounding vM1 layer 5 pyramidal neurons after facial nerve lesion with morphological bias towards the activated phenotype. These results suggest that facial nerve lesions elicit active dendrite remodeling due to pyramidal neuron and microglia interaction, which could be the pathophysiological underpinning of some neuropathic motor sequelae in humans.

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Bobo-Jiménez, Verónica, María Delgado-Esteban, Julie Angibaud, Irene Sánchez-Morán, Antonio de la Fuente, Javier Yajeya, U. Valentin Nägerl, José Castillo, Juan P. Bolaños und Angeles Almeida. „APC/CCdh1-Rock2 pathway controls dendritic integrity and memory“. Proceedings of the National Academy of Sciences 114, Nr. 17 (10.04.2017): 4513–18. http://dx.doi.org/10.1073/pnas.1616024114.

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Disruption of neuronal morphology contributes to the pathology of neurodegenerative disorders such as Alzheimer’s disease (AD). However, the underlying molecular mechanisms are unknown. Here, we show that postnatal deletion of Cdh1, a cofactor of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase in neurons [Cdh1 conditional knockout (cKO)], disrupts dendrite arborization and causes dendritic spine and synapse loss in the cortex and hippocampus, concomitant with memory impairment and neurodegeneration, in adult mice. We found that the dendrite destabilizer Rho protein kinase 2 (Rock2), which accumulates in the brain of AD patients, is an APC/CCdh1 substrate in vivo and that Rock2 protein and activity increased in the cortex and hippocampus of Cdh1 cKO mice. In these animals, inhibition of Rock activity, using the clinically approved drug fasudil, prevented dendritic network disorganization, memory loss, and neurodegeneration. Thus, APC/CCdh1-mediated degradation of Rock2 maintains the dendritic network, memory formation, and neuronal survival, suggesting that pharmacological inhibition of aberrantly accumulated Rock2 may be a suitable therapeutic strategy against neurodegeneration.

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Baudouin, Stéphane J., Julie Angibaud, Gildas Loussouarn, Virginie Bonnamain, Akihiro Matsuura, Miyuki Kinebuchi, Philippe Naveilhan und Hélène Boudin. „The Signaling Adaptor Protein CD3ζ Is a Negative Regulator of Dendrite Development in Young Neurons“. Molecular Biology of the Cell 19, Nr. 6 (Juni 2008): 2444–56. http://dx.doi.org/10.1091/mbc.e07-09-0947.

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A novel idea is emergxsing that a large molecular repertoire is common to the nervous and immune systems, which might reflect the existence of novel neuronal functions for immune molecules in the brain. Here, we show that the transmembrane adaptor signaling protein CD3ζ, first described in the immune system, has a previously uncharacterized role in regulating neuronal development. Biochemical and immunohistochemical analyses of the rat brain and cultured neurons showed that CD3ζ is mainly expressed in neurons. Distribution of CD3ζ in developing cultured hippocampal neurons, as determined by immunofluorescence, indicates that CD3ζ is preferentially associated with the somatodendritic compartment as soon as the dendrites initiate their differentiation. At this stage, CD3ζ was selectively concentrated at dendritic filopodia and growth cones, actin-rich structures involved in neurite growth and patterning. siRNA-mediated knockdown of CD3ζ in cultured neurons or overexpression of a loss-of-function CD3ζ mutant lacking the tyrosine phosphorylation sites in the immunoreceptor tyrosine-based activation motifs (ITAMs) increased dendritic arborization. Conversely, activation of endogenous CD3ζ by a CD3ζ antibody reduced the size of the dendritic arbor. Altogether, our findings reveal a novel role for CD3ζ in the nervous system, suggesting its contribution to dendrite development through ITAM-based mechanisms.

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Germain, Francisco, Eduardo Fernandez und Pedro de la Villa. „Morphometrical analysis of dendritic arborization in axotomized retinal ganglion cells“. European Journal of Neuroscience 18, Nr. 5 (September 2003): 1103–9. http://dx.doi.org/10.1046/j.1460-9568.2003.02842.x.

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Zhang, Zaixiang, Diane M. Casey, Jean-Pierre Julien und Zuoshang Xu. „Normal dendritic arborization in spinal motoneurons requires neurofilament subunit L“. Journal of Comparative Neurology 450, Nr. 2 (16.07.2002): 144–52. http://dx.doi.org/10.1002/cne.10306.

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Liu, Yamei, Yunfei Tang, Jinyu Yan, Dongshu Du, Yang Yang und Fuxue Chen. „Deletion of Kv10.2 Causes Abnormal Dendritic Arborization and Epilepsy Susceptibility“. Neurochemical Research 45, Nr. 12 (08.10.2020): 2949–58. http://dx.doi.org/10.1007/s11064-020-03143-7.

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Richards, Laura A., und Christopher M. Schonhoff. „Nitric oxide and sex differences in dendritic branching and arborization“. Journal of Neuroscience Research 99, Nr. 5 (03.02.2021): 1390–400. http://dx.doi.org/10.1002/jnr.24789.

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Paramo, Blanca, Sean Wyatt und Alun M. Davies. „Neuregulin-4 Is Required for the Growth and Elaboration of Striatal Medium Spiny Neuron Dendrites“. Journal of Neuropathology & Experimental Neurology 78, Nr. 8 (24.05.2019): 725–34. http://dx.doi.org/10.1093/jnen/nlz046.

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Abstract Medium spiny neurons (MSNs) comprise the vast majority of neurons in the striatum. Changes in the exuberant dendrites of these widely connected neurons are associated with a multitude of neurological conditions and are caused by a variety of recreational and medicinal drugs. However, we have a poor understanding of the physiological regulators of dendrite growth and elaboration of this clinically important population of neurons. Here, we show that MSN dendrites are markedly smaller and less branched in neonatal mice that possess a homozygous null mutation in the neuregulin-4 gene (Nrg4−/−) compared with wild type (Nrg4+/+) littermates. Nrg4−/− mice also had a highly significant reduction in MSN dendrite spine number in neonates and adults. The striking stunted dendrite arbor phenotype of MSNs observed in Nrg4−/− neonates was replicated in MSNs cultured from Nrg4−/− embryos and was completely rescued by soluble recombinant neuregulin-4. MSNs cultured from wild type mice coexpressed NRG4 and its receptor ErbB4. Our findings show that NRG4 is a major novel regulator of dendritic growth and arborization and spine formation in the striatum and suggest that it exerts its effects by an autocrine/paracrine mechanism.

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Gogan, P., und S. Tyc-Dumont. „How Do Dendrites Process Neural Information?“ Physiology 4, Nr. 4 (01.08.1989): 127–30. http://dx.doi.org/10.1152/physiologyonline.1989.4.4.127.

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The concept of neuronal computing has been evolving toward the idea that the three-dimensional form of dendritic arborization determines the computational abilities of the neuron. The architectural complexity of every single neuron in the brain is probably as important as connectivity for the performance of a neural network.

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Malis, Milos, Valentina Nikolic, Vuk Djulejic, Dejan Opric, Lukas Rasulic und Laslo Puskas. „Morphometric characteristics of Neuropeptide Y immunoreactive neurons of human cortical amygdaloid nucleus“. Medical review 61, Nr. 5-6 (2008): 235–41. http://dx.doi.org/10.2298/mpns0806235m.

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Introduction Cortical amygdaloid nucleus belongs to the corticomedial part of the amygdaloid complex. In this nucleus there are neurons that produce neuropetide Y. This peptide has important roles in sleeping, learning, memory, gastrointestinal regulation, anxiety, epilepsy, alcoholism and depression. Material and methods We investigated morphometric characteristics (numbers of primary dendrites, longer and shorter diameters of cell bodies and maximal radius of dendritic arborization) of NPY immunoreactive neurons of human cortical amygdaloid nucleus on 6 male adult human brains, aged 46 to 77 years, by immunohistochemical avidin-biotin technique. Results Our investigation has shown that in this nucleus there is a moderate number of NPY immunoreactive neurons. 67% of found neurons were nonpyramidal, while 33% were pyramidal. Among the nonpyramidal neurons the dominant groups were multipolar neurons (41% - of which 25% were multipolar irregular, and 16% multipolar oval). Among the pyramidal neurons the dominant groups were the neurons with triangular shape of cell body (21%). All found NPY immunoreactive neurons (pyramidal and nonpyramidal altogether) had intervals of values of numbers of primary dendrites 2 to 6, longer diameters of cell bodies 13 to 38 ?m, shorter diameters of cell bodies 9 to 20 ?m and maximal radius of dendritic arborization 50 to 340 ?m. More than a half of investigated neurons (57%) had 3 primary dendrites. Discussion and conclusion The other researchers did not find such percentage of pyramidal immunoreactive neurons in this amygdaloid nucleus. If we compare our results with the results of the ather researchers we can conclude that all pyramidal NPY immunoreactive neurons found in this human amygdaloid nucleus belong to the class I of neurons, and that all nonpyramidal NPY immunoreactive neurons belong to the class II of neurons described by other researchers. We suppose that all found pyramidal neurons were projectional.

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Ichikawa, T. „MOTION-SENSITIVE CELLS: PUTATIVE LARVAL NEURONES INCORPORATED INTO THE OPTIC LOBE OF THE ADULT SWALLOWTAIL BUTTERFLY“. Journal of Experimental Biology 195, Nr. 1 (01.10.1994): 361–80. http://dx.doi.org/10.1242/jeb.195.1.361.

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Intracellular recordings were made from neurones with large somata situated at the anteromedial edge of the medulla of the swallowtail butterfly Papilio xuthus; the neurones were then filled with Lucifer Yellow. These cells are putative larval visual interneurones incorporated into the adult optic lobe of the butterfly. There are four classes of motion-sensitive neurones. Two have a dendritic arborization in the dorsal half of the medulla and project an axon to the medial protocerebrum or the contralateral medulla. They respond to vertical downward motion with a strong burst of action potentials and their background activities are inhibited by motion in the opposite direction. Variations in position of the dendritic fields suggest that each group of neurones forms a coherent set of cells detecting vertical motion in the dorsal half of the visual field of the eye. The third class of neurones connects the lobula plate to the midbrain and is preferentially sensitive to vertical upward motion. The fourth class of neurones has a dendritic arborization in the lobula. These neurones are tonically excited by a moving grating irrespective of the stimulus orientation and movement direction. The presence of motion-sensitive medulla neurones suggests that the detection of local motion is completed in the distal medulla.

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Aguirre-Chen, Cristina, Natalia Stec, Olivia Mendivil Ramos, Nuri Kim, Melissa Kramer, Shane McCarthy, Jesse Gillis, W. Richard McCombie und Christopher M. Hammell. „A Caenorhabditis elegans Model for Integrating the Functions of Neuropsychiatric Risk Genes Identifies Components Required for Normal Dendritic Morphology“. G3: Genes|Genomes|Genetics 10, Nr. 5 (04.03.2020): 1617–28. http://dx.doi.org/10.1534/g3.119.400925.

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Analysis of patient-derived DNA samples has identified hundreds of variants that are likely involved in neuropsychiatric diseases such as autism spectrum disorder (ASD) and schizophrenia (SCZ). While these studies couple behavioral phenotypes to individual genotypes, the number and diversity of candidate genes implicated in these disorders highlights the fact that the mechanistic underpinnings of these disorders are largely unknown. Here, we describe a RNAi-based screening platform that uses C. elegans to screen candidate neuropsychiatric risk genes (NRGs) for roles in controlling dendritic arborization. To benchmark this approach, we queried published lists of NRGs whose variants in ASD and SCZ are predicted to result in complete or partial loss of gene function. We found that a significant fraction (>16%) of these candidate NRGs are essential for dendritic development. Furthermore, these gene sets are enriched for dendritic arbor phenotypes (>14 fold) when compared to control RNAi datasets of over 500 human orthologs. The diversity of PVD structural abnormalities observed in these assays suggests that the functions of diverse NRGs (encoding transcription factors, chromatin remodelers, molecular chaperones and cytoskeleton-related proteins) converge to regulate neuronal morphology and that individual NRGs may play distinct roles in dendritic branching. We also demonstrate that the experimental value of this platform by providing additional insights into the molecular frameworks of candidate NRGs. Specifically, we show that ANK2/UNC-44 function is directly integrated with known regulators of dendritic arborization and suggest that altering the dosage of ARID1B/LET-526 expression during development affects neuronal morphology without diminishing aspects of cell fate specification.

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Blizinsky, Katherine D., Blanca Diaz-Castro, Marc P. Forrest, Britta Schürmann, Anthony P. Bach, Maria Dolores Martin-de-Saavedra, Lei Wang, John G. Csernansky, Jubao Duan und Peter Penzes. „Reversal of dendritic phenotypes in 16p11.2 microduplication mouse model neurons by pharmacological targeting of a network hub“. Proceedings of the National Academy of Sciences 113, Nr. 30 (11.07.2016): 8520–25. http://dx.doi.org/10.1073/pnas.1607014113.

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The architecture of dendritic arbors contributes to neuronal connectivity in the brain. Conversely, abnormalities in dendrites have been reported in multiple mental disorders and are thought to contribute to pathogenesis. Rare copy number variations (CNVs) are genetic alterations that are associated with a wide range of mental disorders and are highly penetrant. The 16p11.2 microduplication is one of the CNVs most strongly associated with schizophrenia and autism, spanning multiple genes possibly involved in synaptic neurotransmission. However, disease-relevant cellular phenotypes of 16p11.2 microduplication and the driver gene(s) remain to be identified. We found increased dendritic arborization in isolated cortical pyramidal neurons from a mouse model of 16p11.2 duplication (dp/+). Network analysis identified MAPK3, which encodes ERK1 MAP kinase, as the most topologically important hub in protein–protein interaction networks within the 16p11.2 region and broader gene networks of schizophrenia-associated CNVs. Pharmacological targeting of ERK reversed dendritic alterations associated with dp/+ neurons, outlining a strategy for the analysis and reversal of cellular phenotypes in CNV-related psychiatric disorders.

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