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The Caenorhabditis elegans homologue of the proto-oncogene ect-2 positively regulates RAS signalling during vulval development.

ABSTRACT: Guanine nucleotide exchange factors (GEFs) regulate the activity of small GTP-binding proteins in a variety of biological processes. We have identified a gain-of-function mutation in the Caenorhabditis elegans GEF ect-2, the homologue of the mammalian ect2 proto-oncogene that has an essential role during cytokinesis. Here, we report that, in addition to its known function during mitosis, ECT-2 promotes the specification of the primary vulval cell fate by activating RAS/mitogen-activated protein kinase (MAPK) signalling before the end of the S-phase. Epistasis analysis indicates that ECT-2 crosstalks to the canonical RAS/MAPK cascade upstream of the RAS GEF SOS-1 by means of a RHO-1 signalling pathway. Our results raise the possibility that the transforming activity of the mammalian ect-2 oncogene could be due to hyperactivation of the RAS/MAPK pathway.

SUBMITTER: Canevascini S

PROVIDER: S-EPMC1369209 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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The Caenorhabditis elegans homologue of the proto-oncogene ect-2 positively regulates RAS signalling during vulval development.

Canevascini Stefano S Marti Mark M Fröhli Erika E Hajnal Alex A

EMBO reports 20051201 12

Guanine nucleotide exchange factors (GEFs) regulate the activity of small GTP-binding proteins in a variety of biological processes. We have identified a gain-of-function mutation in the Caenorhabditis elegans GEF ect-2, the homologue of the mammalian ect2 proto-oncogene that has an essential role during cytokinesis. Here, we report that, in addition to its known function during mitosis, ECT-2 promotes the specification of the primary vulval cell fate by activating RAS/mitogen-activated protein ...[more]

PMID: 16270101

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