Plexin‐B1 is a GTPase activating protein for M‐Ras, remodelling dendrite morphology
Open Access
- 15 May 2009
- journal article
- research article
- Published by Springer Science and Business Media LLC in EMBO Reports
- Vol. 10 (6), 614-621
- https://doi.org/10.1038/embor.2009.63
Abstract
Plexins are receptors for axonal guidance molecules known as semaphorins. We recently reported that the semaphorin 4D (Sema4D) receptor, Plexin‐B1, induces axonal growth cone collapse by functioning as an R‐Ras GTPase activating protein (GAP). Here, we report that Plexin‐B1 shows GAP activity for M‐Ras, another member of the Ras family of GTPases. In cortical neurons, the expression of M‐Ras was upregulated during dendritic development. Knockdown of endogenous M‐Ras—but not R‐Ras—reduced dendritic outgrowth and branching, whereas overexpression of constitutively active M‐Ras, M‐Ras(Q71L), enhanced dendritic outgrowth and branching. Sema4D suppressed M‐Ras activity and reduced dendritic outgrowth and branching, but this reduction was blocked by M‐Ras(Q71L). M‐Ras(Q71L) stimulated extracellular signal‐regulated kinase (ERK) activation, inducing dendrite growth, whereas Sema4D suppressed ERK activity and down‐regulation of ERK was required for a Sema4D‐induced reduction of dendrite growth. Thus, we conclude that Plexin‐B1 is a dual functional GAP for R‐Ras and M‐Ras, remodelling axon and dendrite morphology, respectively.Keywords
This publication has 22 references indexed in Scilit:
- R-Ras Controls Axon Specification Upstream of Glycogen Synthase Kinase-3β through Integrin-linked KinaseJournal of Biological Chemistry, 2007
- The Semaphorin 4D Receptor Plexin-B1 Is a GTPase Activating Protein for R-RasScience, 2004
- The Control of Dendrite DevelopmentNeuron, 2003
- Ras GTPases: integrins' friends or foes?Nature Reviews Molecular Cell Biology, 2003
- The semaphorin receptor plexin-B1 signals through a direct interaction with the Rho-specific nucleotide exchange factor, LARGProceedings of the National Academy of Sciences, 2002
- R-Ras3/M-Ras Induces Neuronal Differentiation of PC12 Cells through Cell-Type-Specific Activation of the Mitogen-Activated Protein Kinase CascadeMolecular and Cellular Biology, 2002
- Plexin-B1 Directly Interacts with PDZ-RhoGEF/LARG to Regulate RhoA and Growth Cone MorphologyNeuron, 2002
- Activation of Phosphoinositide 3-Kinase γ by RasCurrent Biology, 2002
- Regulatory Proteins of R-Ras, TC21/R-Ras2, and M-Ras/R-Ras3Journal of Biological Chemistry, 2000
- The semaphorin genes encode a family of transmembrane and secreted growth cone guidance moleculesCell, 1993