title: Pak1 is involved in dendrite initiation as a downstream effector of Rac1 in cortical neurons.
abstract: Dendrite development in neurons is one of the bases for the formation of a complex neuronal network in the nervous system, and involvement of the Rho family GTPases, including Rac1, Cdc42, and RhoA, in dendrite formation has been demonstrated. One of the effectors of Rac1 and Cdc42, p21-activated kinase 1 (Pak1), is abundant in the brain; however, the function of Pak1 in neurons remains unknown. In order to clarify the roles of Pak1 in neurons, we introduced mutant Pak1 into immature neurons by a novel gene transfer technique using in utero electroporation. Introduction of constitutive active (CA)-Pak1 led to increase the number of dendrites, whereas introduction of dominant negative (DN)-Pak1 caused a reduction, and coexpression of CA-Rac1 and DN-Pak1 also resulted in a reduction in the number of dendrites. These results suggest that Pak1 regulates dendrite initiation as a downstream effector of Rac1.
authors.affiliation: Laboratory for Developmental Neurobiology, Brain Science Institute, RIKEN, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Kanehiro
authors.initials: K
authors.lastname: Hayashi
authors.forename: Toshio
authors.initials: T
authors.lastname: Ohshima
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Mikoshiba
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism*; D003712:Dendrites / Q000502:physiology; D004622:Embryo, Mammalian; D004789:Enzyme Activation / Q000502:physiology; D018014:Gene Transfer Techniques; D005799:Genes, Dominant; D006801:Humans; D051379:Mice; D008813:Mice, Inbred ICR; D009474:Neurons / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000502:physiology*; D014018:Tissue Distribution; D020764:cdc42 GTP-Binding Protein / Q000502:physiology; D054462:p21-Activated Kinases; D020830:rac1 GTP-Binding Protein / Q000378:metabolism*; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D017346:Protein Serine-Threonine Kinases; D054462:p21-Activated Kinases; D020764:cdc42 GTP-Binding Protein; D020830:rac1 GTP-Binding Protein; D020741:rho GTP-Binding Proteins