Plexin-a4 Receptor Regulates Dendrite Morphogenesis in Response to Class 3 Semaphorin 3a Signaling in Mouse Pyramidal Neurons
نویسنده
چکیده
The formation of a complex nervous system requires precise navigation and elaboration for growth cone and dendrites to connect to their target. During development, guidance molecules and receptors control the majority of the circuitry events, including promotion or inhibition of neurite growth. Semaphorin 3A, a secreted Class 3 Semaphorin member, is well known for its chemorepellent function on growth cone mediated by the Neuropilin1/PlexinA4 holoreceptor complex. Recently, it has been shown to have opposite cellular responses in promoting dendrite growth and branching in mouse cortical pyramidal neurons (1, 2). However, the mechanism underlying how Semaphorin 3A/Neuropilin1/Plexin-A4 signaling regulates dendrite elaboration is unclear. Here, I have shown the importance and function of three distinct domains in the cytoplasmic region of the signaling transducing receptor of Semaphorin 3A, Plexin-A4, in regulating cortical neuron dendritic morphology. Both the C1 and H/RBD domains were found to be sufficient to trigger cortical pyramidal neuron dendrite elaboration, while the C2 domain was not necessary for dendrites growth and branching. Using biochemical and molecular methods in combination with in vitro assays, I found and
منابع مشابه
Differential Requirement for Plexin-A3 and -A4 in Mediating Responses of Sensory and Sympathetic Neurons to Distinct Class 3 Semaphorins
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