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PubMed · 12372594

B plexins activate Rho through PDZ-RhoGEF.

Mariette H E Driessens·Cristina Olivo·Koh-ichi Nagata·Masaki Inagaki·John G Collard
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Abstract

Plexins are receptors for the repulsive axon guidance molecules semaphorins. Previously, we have shown that plexin-B1 binds activated Rac, but that clustering of plexin-B1 causes Rho activation, resulting in stress fiber formation. Using the yeast two-hybrid system, we found that the C-terminus of B plexins interacted directly with Rho-specific exchange factors, via their PDZ domain. Mutation of the carboxy-terminal amino acids of plexin-B1 or coexpression of a dominant negative PDZ-RhoGEF abrogated the ability of plexin-B1 to cause stress fiber formation. Our results demonstrate a role for PDZ-RhoGEF in B plexin-mediated activation of Rho/Rho kinase signaling, implicated in the regulation of axon guidance and cell migration.

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3T3 CellsAnimalsCell LineEnzyme ActivationGTP-Binding ProteinsGuanine Nucleotide Exchange FactorsHumansMiceNerve Tissue ProteinsProtein BindingReceptors, Cell SurfaceSignal TransductionTwo-Hybrid System TechniquesJournal ArticleResearch Support, Non-U.S. Gov't

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Mariette H E Driessens, Cristina Olivo, Koh-ichi Nagata, Masaki Inagaki, John G Collard. 2002-10-09. B plexins activate Rho through PDZ-RhoGEF.. https://doi.org/10.1016/s0014-5793(02)03323-9

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