title: Sema4D-plexin-B1 implicated in regulation of dendritic spine density through RhoA/ROCK pathway.
abstract: Plexin-B1, Sema4D receptor, mediates retraction and extension signals in axon guidance by associating with PDZ-containing Rho guanine nucleotide exchange factors (PDZ-RhoGEFs) which can activate a small Rho GTPase RhoA. RhoA is implicated in spine formation by rearranging actin cytoskeleton. Exogenous application of Sema4D to cultured neurons caused activation of RhoA, increase of spine density and changes in spine shape. Sema4D-induced changes in spine density were blocked by either Rho-kinase (a downstream of RhoA, ROCK) inhibitor Y-27632 or by overexpression of plexin-B1 mutant lacking the C-terminus which no longer associates with PDZ-RhoGEFs. This study suggests that Sema4D-plexin-B1 play a crucial role in spine formation by regulating RhoA/ROCK pathway.
authors.affiliation: Department of Anatomy and Neuroscience, Osaka University Graduate School of Medicine, Yamadaoka 2-2, Suita, Osaka, Japan.
authors.forename: Xianzong
authors.initials: X
authors.lastname: Lin
authors.forename: Mariko
authors.initials: M
authors.lastname: Ogiya
authors.forename: Mizue
authors.initials: M
authors.lastname: Takahara
authors.forename: Wataru
authors.initials: W
authors.lastname: Yamaguchi
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Furuyama
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Tanaka
authors.forename: Masaya
authors.initials: M
authors.lastname: Tohyama
authors.forename: Shinobu
authors.initials: S
authors.lastname: Inagaki
mesh_terms: D000577:Amides / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D049229:Dendritic Spines / Q000187:drug effects* / Q000502:physiology* / Q000648:ultrastructure; D000076122:Disks Large Homolog 4 Protein; D004622:Embryo, Mammalian; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D020690:GTPase-Activating Proteins / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D009154:Mutation / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D011956:Receptors, Cell Surface / Q000502:physiology*; D039961:Semaphorins / Q000494:pharmacology*; D014162:Transfection; D020741:rho GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D000577:Amides; D000076122:Disks Large Homolog 4 Protein; C501449:Dlg4 protein, rat; D004791:Enzyme Inhibitors; D020690:GTPase-Activating Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C488752:Plxnb1 protein, rat; D011725:Pyridines; D011956:Receptors, Cell Surface; C103150:Sema4d protein, mouse; D039961:Semaphorins; C108830:Y 27632; D020741:rho GTP-Binding Proteins