title: CRMP4 suppresses apical dendrite bifurcation of CA1 pyramidal neurons in the mouse hippocampus.
abstract: Collapsin response mediator proteins (CRMPs) are a family of cytosolic phosphoproteins that consist of 5 members (CRMP 1-5). CRMP2 and CRMP4 regulate neurite outgrowth by binding to tubulin heterodimers, resulting in the assembly of microtubules. CRMP2 also mediates the growth cone collapse response to the repulsive guidance molecule semaphorin-3A (Sema3A). However, the role of CRMP4 in Sema3A signaling and its function in the developing mouse brain remain unclear. 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. We also observed increased dendritic branching in cultured CRMP4-/- hippocampal neurons as well as in cultured cortical neurons treated with CRMP4 shRNA. Sema3A induces extension and branching of the dendrites of hippocampal neurons; however, these inductions were compromised in the CRMP4-/- hippocampal neurons. 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.
authors.affiliation: Department of Life Science and Medical Bioscience, Waseda University, Tokyo 162-8480, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Niisato
authors.forename: Jun
authors.initials: J
authors.lastname: Nagai
authors.forename: Naoya
authors.initials: N
authors.lastname: Yamashita
authors.forename: Takaya
authors.initials: T
authors.lastname: Abe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kiyonari
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Goshima
authors.forename: Toshio
authors.initials: T
authors.lastname: Ohshima
mesh_terms: D000818:Animals; D001921:Brain / Q000254:growth & development / Q000502:physiology; D056547:CA1 Region, Hippocampal / Q000502:physiology*; D002478:Cells, Cultured; D003712:Dendrites / Q000502:physiology*; D020439:Growth Cones / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000502:physiology*; D017966:Pyramidal Cells / Q000502:physiology*; D034741:RNA, Small Interfering; D040121:Semaphorin-3A / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology
chemical_list: C526904:Dpysl3 protein, mouse; D009419:Nerve Tissue Proteins; D034741:RNA, Small Interfering; C488217:Sema3a protein, mouse; D040121:Semaphorin-3A