Brain cell biology最新文献_第4页

Synapsin II negatively regulates catecholamine release. 突触素II负性调节儿茶酚胺释放。

Brain cell biology Pub Date : 2006-06-01 Epub Date: 2007-10-04 DOI: 10.1007/s11068-007-9015-2

Melissa Villanueva, Keith Thornley, George J Augustine, R Mark Wightman

{"title":"Synapsin II negatively regulates catecholamine release.","authors":"Melissa Villanueva, Keith Thornley, George J Augustine, R Mark Wightman","doi":"10.1007/s11068-007-9015-2","DOIUrl":"https://doi.org/10.1007/s11068-007-9015-2","url":null,"abstract":"We have assessed the role of synapsins in catecholamine release by comparing the properties of exocytosis in adrenal chromaffin cells from wild-type and synapsin triple knock-out (TKO) mice. Brief depolarizations led to a greater amount of catecholamine release in chromaffin cells from TKO mice in comparison to chromaffin cells from wild-type mice. This increase in catecholamine release was due to an increased number of exocytotic events, while the properties of individual quanta of released catecholamine were unchanged. Barium ions produced similar amounts of catecholamine release from TKO and wild-type chromaffin cells, suggesting that the reserve pool of chromaffin granules is unchanged following loss of synapsins. Because expression of synapsin IIa in TKO chromaffin cells rescued the defect in depolarization-induced exocytosis, the TKO phenotype apparently results from loss of synapsin IIa. We conclude that synapsin IIa serves as a negative regulator of catecholamine release and that this protein influences exocytosis from a readily releasable pool of chromaffin granules. Further, because these defects in catecholamine release are different from those observed for glutamate and GABA release in TKO mice, we conclude that the functions of synapsins differ for vesicles containing different types of neurotransmitters.","PeriodicalId":72445,"journal":{"name":"Brain cell biology","volume":"35 2-3","pages":"125-36"},"PeriodicalIF":0.0,"publicationDate":"2006-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s11068-007-9015-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27066727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27

Cross talk between vestibular neurons and Schwann cells mediates BDNF release and neuronal regeneration. 前庭神经元和雪旺细胞之间的串音介导BDNF释放和神经元再生。

Brain cell biology Pub Date : 2006-06-01 Epub Date: 2007-10-04 DOI: 10.1007/s11068-007-9011-6

Claudia Verderio, Fabio Bianco, Marie Pierre Blanchard, Matteo Bergami, Marco Canossa, Eric Scarfone, Michela Matteoli

{"title":"Cross talk between vestibular neurons and Schwann cells mediates BDNF release and neuronal regeneration.","authors":"Claudia Verderio, Fabio Bianco, Marie Pierre Blanchard, Matteo Bergami, Marco Canossa, Eric Scarfone, Michela Matteoli","doi":"10.1007/s11068-007-9011-6","DOIUrl":"https://doi.org/10.1007/s11068-007-9011-6","url":null,"abstract":"It is now well-established that an active cross-talk occurs between neurons and glial cells, in the adult as well as in the developing and regenerating nervous systems. These functional interactions not only actively modulate synaptic transmission, but also support neuronal growth and differentiation. We have investigated the possible existence of a reciprocal interaction between inner ear vestibular neurons and Schwann cells maintained in primary cultures. We show that ATP released by the extending vestibular axons elevates intracellular calcium levels within Schwann cells. Purinergic activation of the Schwann P2X(7) receptor induces the release of neurotrophin BDNF, which occurs via a regulated, tetanus-toxin sensitive, vesicular pathway. BDNF, in turn, is required by the vestibular neuron to support its own survival and growth. Given the massive release of ATP during tissue damage, cross-talk between vestibular neurons and Schwann cells could play a primary role during regeneration.","PeriodicalId":72445,"journal":{"name":"Brain cell biology","volume":"35 2-3","pages":"187-201"},"PeriodicalIF":0.0,"publicationDate":"2006-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s11068-007-9011-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27066731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 41

Vesicle pools and synapsins: new insights into old enigmas. 囊泡池和突触:对老谜团的新见解。

Brain cell biology Pub Date : 2006-06-01 Epub Date: 2007-10-04 DOI: 10.1007/s11068-007-9013-4

Elena Fdez, Sabine Hilfiker

引用次数: 94

Cell type-specific dendritic polarity in the absence of spatially organized external cues. 在没有空间组织外部线索的情况下细胞类型特异性树突极性。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-02-27 DOI: 10.1007/s11068-006-9003-y

April C Horton, Jason J Yi, Michael D Ehlers

引用次数: 23

Calcium-dependent trapping of mitochondria near plasma membrane in stimulated astrocytes. 受刺激星形胶质细胞质膜附近线粒体的钙依赖性捕获。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-03-10 DOI: 10.1007/s11068-006-9000-1

Julia Kolikova, Ramil Afzalov, Asiya Giniatullina, Alexander Surin, Rashid Giniatullin, Leonard Khiroug

{"title":"Calcium-dependent trapping of mitochondria near plasma membrane in stimulated astrocytes.","authors":"Julia Kolikova, Ramil Afzalov, Asiya Giniatullina, Alexander Surin, Rashid Giniatullin, Leonard Khiroug","doi":"10.1007/s11068-006-9000-1","DOIUrl":"https://doi.org/10.1007/s11068-006-9000-1","url":null,"abstract":"Growing evidence suggests that astrocytes are the active partners of neurons in many brain functions. Astrocytic mitochondria are highly motile organelles which regulate the temporal and spatial patterns of Ca( 2+ ) dynamics, in addition to being a major source of ATP and reactive oxygen species. Previous studies have shown that mitochondria translocate to endoplasmic reticulum during Ca( 2+ ) release from internal stores, but whether a similar spatial interaction between mitochondria and plasma membrane occurs is not known. Using total internal reflection fluorescence (TIRF) microscopy we show that a fraction of mitochondria became trapped near the plasma membrane of cultured hippocampal astrocytes during exposure to the transmitters glutamate or ATP, resulting in net translocation of the mitochondria to the plasma membrane. This translocation was dependent on the intracellular Ca( 2+ ) rise because it was blocked by pre-incubation with BAPTA AM and mimicked by application of the Ca( 2+ ) ionophore ionomycin. Transmembrane Ca( 2+ ) influx induced by raising external Ca( 2+ ) also caused mitochondrial trapping, which occurred more rapidly than that produced by glutamate or ATP. In astrocytes treated with the microtubule-disrupting agent nocodazole, intracellular Ca( 2+ ) rises failed to induce trapping of mitochondria near plasma membrane, suggesting a role for microtubules in this phenomenon. Our data reveal the Ca( 2+ )-dependent trapping of mitochondria near the plasma membrane as a novel form of mitochondrial regulation, which is likely to control the perimembrane Ca( 2+ ) dynamics and regulate signaling by mitochondria-derived reactive oxygen species.","PeriodicalId":72445,"journal":{"name":"Brain cell biology","volume":"35 1","pages":"75-86"},"PeriodicalIF":0.0,"publicationDate":"2006-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s11068-006-9000-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27052810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

Electrical coupling between pyramidal cells in adult cortical regions. 成人皮层锥体细胞间的电偶联。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-02-27 DOI: 10.1007/s11068-006-9005-9

Audrey Mercer, A Peter Bannister, Alex M Thomson

引用次数: 88

Calcium-induced exocytosis from actomyosin-driven, motile varicosities formed by dynamic clusters of organelles. 钙诱导的胞吐是由肌动球蛋白驱动的，由动态细胞器簇形成的运动性变异。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-03-10 DOI: 10.1007/s11068-006-9007-7

Guy Malkinson, Zohar M Fridman, Dotan Kamber, Ada Dormann, Eli Shapira, Micha E Spira

{"title":"Calcium-induced exocytosis from actomyosin-driven, motile varicosities formed by dynamic clusters of organelles.","authors":"Guy Malkinson, Zohar M Fridman, Dotan Kamber, Ada Dormann, Eli Shapira, Micha E Spira","doi":"10.1007/s11068-006-9007-7","DOIUrl":"https://doi.org/10.1007/s11068-006-9007-7","url":null,"abstract":"Varicosities are ubiquitous neuronal structures that appear as local swellings along neurites of invertebrate and vertebrate neurons. Surprisingly little is known about their cell biology. We use here cultured Aplysia neurons and demonstrate that varicosities are motile compartments that contain large clusters of organelles. The content of varicosities propagate along neurites within the plasma membrane \"sleeve\", split and merge, or wobble in place. Confocal imaging, retrospective immunolabeling, electron microscopy and pharmacological perturbations reveal that the motility of the varicosities' organelle content occurs in concert with an actin scaffold and is generated by actomyosin motors. Despite the motility of these organelle clusters within the cytoplasm along the neurites, elevation of the free intracellular calcium concentration within varicosities by trains of action potentials induces exocytosis followed by membrane retrieval. Our observations demonstrate that varicosities formed in the absence of postsynaptic cells behave as \"ready to go\" prefabricated presynaptic terminals. We suggest that the varicosities' motility serves to increase the probability of encountering a postsynaptic cell and to rapidly form a functional synapse.","PeriodicalId":72445,"journal":{"name":"Brain cell biology","volume":"35 1","pages":"57-73"},"PeriodicalIF":0.0,"publicationDate":"2006-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s11068-006-9007-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27052809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Requirement of TrkB for synapse elimination in developing cerebellar Purkinje cells. TrkB对发育中的小脑浦肯野细胞突触消除的需求。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-03-01 DOI: 10.1007/s11068-006-9002-z

Laurens W J Bosman, Jana Hartmann, Jaroslaw J Barski, Alexandra Lepier, Michael Noll-Hussong, Louis F Reichardt, Arthur Konnerth

引用次数: 55

A microtubule-based, dynein-dependent force induces local cell protrusions: Implications for neurite initiation. 基于微管的动力蛋白依赖力诱导局部细胞突起:对神经突起始的影响。

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-03-13 DOI: 10.1007/s11068-006-9001-0

L Dehmelt, P Nalbant, W Steffen, S Halpain

{"title":"A microtubule-based, dynein-dependent force induces local cell protrusions: Implications for neurite initiation.","authors":"L Dehmelt, P Nalbant, W Steffen, S Halpain","doi":"10.1007/s11068-006-9001-0","DOIUrl":"https://doi.org/10.1007/s11068-006-9001-0","url":null,"abstract":"A key event in neurite initiation is the accumulation of microtubule bundles at the neuron periphery. We hypothesized that such bundled microtubules may generate a force at the plasma membrane that facilitates neurite initiation. To test this idea we observed the behavior of microtubule bundles that were induced by the microtubule-associated protein MAP2c. Endogenous MAP2c contributes to neurite initiation in primary neurons, and exogeneous MAP2c is sufficient to induce neurites in Neuro-2a cells. We performed nocodazol washout experiments in primary neurons, Neuro-2a cells and COS-7 cells to investigate the underlying mechanism. During nocodazol washout, small microtubule bundles formed rapidly in the cytoplasm and immediately began to move toward the cell periphery in a unidirectional manner. In neurons and Neuro-2a cells, neurite-like processes extended within minutes and concurrently accumulated bundles of repolymerized microtubules. Speckle microscopy in COS-7 cells indicated that bundle movement was due to transport, not treadmilling. At the periphery bundles remained under a unidirectional force and induced local cell protrusions that were further enhanced by suppression of Rho kinase activity. Surprisingly, this bundle motility was independent of classical actin- or microtubule-based tracks. It was, however, reversed by function-blocking antibodies against dynein. Suppression of dynein expression in primary neurons by RNA interference severely inhibited the generation of new neurites, but not the elongation of existing neurites formed prior to dynein knockdown. Together, these cell biological data suggest that neuronal microtubule-associated proteins induce microtubule bundles that are pushed outward by dynein and locally override inward contraction to initiate neurite-like cell protrusions. A similar force-generating mechanism might participate in spontaneous initiation of neurites in developing neurons.","PeriodicalId":72445,"journal":{"name":"Brain cell biology","volume":"35 1","pages":"39-56"},"PeriodicalIF":0.0,"publicationDate":"2006-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s11068-006-9001-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"27052808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 78

Pyramid power: principal cells of the hippocampus unite! 金字塔力量:海马体的主要细胞联合起来!

Brain cell biology Pub Date : 2006-02-01 Epub Date: 2007-03-10 DOI: 10.1007/s11068-006-9004-x

Michael V L Bennett, Alberto Pereda

引用次数: 22