#Apical dendrite pro
Pro pyramidový neuron je charakteristické trojúhelníkovité bunné tlo, jediný axon, velký apikální dendrit, mnohonásobné bazální dendrity a dále také pítomnost. Chronic stress has been shown to reduce the arbor complexity and total dendritic length of apical dendrite trees of CA3 pyramidal neurons in the hippocampus as well. These results suggest that CRMP4 suppresses apical dendrite bifurcation of CA1 pyramidal neurons in the mouse hippocampus and that this is partly dependent on Sema3A signaling. Other key structural features of the pyramidal cell are a single axon, a large apical dendrite, multiple basal dendrites, and the presence of dendritic spines. Sema3A induces extension and branching of the dendrites of hippocampal neurons however, these inductions were compromised in the CRMP4−/− hippocampal neurons. We also observed increased dendritic branching in cultured CRMP4−/− hippocampal neurons as well as in cultured cortical neurons treated with CRMP4 shRNA. We generated CRMP4−/− mice in order to study the in vivo function of CRMP4 and identified a phenotype of proximal bifurcation of apical dendrites in the CA1 pyramidal neurons of CRMP4−/− mice. It is proposed that a major function of the apical dendrite is to produce sustained oscillations at a specific frequency that can serve as a common timing unit for the processing of information in circuits connected to that apical dendrite. Since the apical dendrite is the main site of synaptic integration, it is possible that a dysfunctional apical dendrite would selectively impair the ability of Betz cells to be modulated, and therefore conveying cerebral cortex’s message to the spinal cord targets would be impaired, leading to their selective vulnerability. However, the role of CRMP4 in Sema3A signaling and its function in the developing mouse brain remain unclear. Bundles of relatively long apical dendrites dominate the neurons that make up the thickness of the cerebral cortex. CRMP2 also mediates the growth cone collapse response to the repulsive guidance molecule semaphorin-3A (Sema3A). CRMP2 and CRMP4 regulate neurite outgrowth by binding to tubulin heterodimers, resulting in the assembly of microtubules. Collapsin response mediator proteins (CRMPs) are a family of cytosolic phosphoproteins that consist of 5 members (CRMP 1–5).
0 kommentar(er)
