title: The Rho guanine nucleotide exchange factors Intersectin 1L and β-Pix control calcium-regulated exocytosis in neuroendocrine PC12 cells.
abstract: GTPases of the Rho family are molecular switches that play an important role in a wide range of membrane-trafficking processes including neurotransmission and hormone release. We have previously demonstrated that RhoA and Cdc42 regulate calcium-dependent exocytosis in chromaffin cells by controlling actin dynamics, whereas Rac1 regulates lipid organisation. These findings raised the question of the upstream mechanism activating these GTPases during exocytosis. The guanine nucleotide exchange factors (GEFs) that catalyse the exchange of GDP for GTP are crucial elements regulating Rho signalling. Using an RNA interference approach, we have recently demonstrated that the GEFs Intersectin-1L and β-Pix, play essential roles in neuroendocrine exocytosis by controlling the activity of Cdc42 and Rac1, respectively. This review summarizes these results and discusses the functional importance of Rho GEFs in the exocytotic machinery in neuroendocrine cells.
authors.affiliation: CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Université de Strasbourg, 5 rue Blaise Pascal, 67084 Strasbourg, France.
authors.forename: F
authors.initials: F
authors.lastname: Momboisse
authors.forename: S
authors.initials: S
authors.lastname: Ory
authors.forename: M
authors.initials: M
authors.lastname: Ceridono
authors.forename: V
authors.initials: V
authors.lastname: Calco
authors.forename: N
authors.initials: N
authors.lastname: Vitale
authors.forename: M-F
authors.initials: MF
authors.lastname: Bader
authors.forename: S
authors.initials: S
authors.lastname: Gasman
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D005089:Exocytosis; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism*; D055099:Neuroendocrine Cells / Q000378:metabolism*; D016716:PC12 Cells; D051381:Rats; D064067:Rho Guanine Nucleotide Exchange Factors
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D020662:Guanine Nucleotide Exchange Factors; D064067:Rho Guanine Nucleotide Exchange Factors; C115919:intersectin 1; D002118:Calcium