The GEX-2 and GEX-3 proteins are required for tissue morphogenesis and cell migrations in C. elegans
AuthorsSoto, Martha C.
Mello, Craig C.
UMass Chan AffiliationsProgram in Molecular Medicine and Cell Biology
Document TypeJournal Article
Keywords*Adaptor Proteins, Signal Transducing
Amino Acid Sequence
Caenorhabditis elegans Proteins
Molecular Sequence Data
Sequence Homology, Amino Acid
rac GTP-Binding Proteins
Medicine and Health Sciences
MetadataShow full item record
AbstractDuring body morphogenesis precisely coordinated cell movements and cell shape changes organize the newly differentiated cells of an embryo into functional tissues. Here we describe two genes, gex-2 and gex-3, whose activities are necessary for initial steps of body morphogenesis in Caenorhabditis elegans. In the absence of gex-2 and gex-3 activities, cells differentiate properly but fail to become organized. The external hypodermal cells fail to spread over and enclose the embryo and instead cluster on the dorsal side. Postembryonically gex-3 activity is required for egg laying and for proper morphogenesis of the gonad. GEX-2 and GEX-3 proteins colocalize to cell boundaries and appear to directly interact. GEX-2 and GEX-3 are highly conserved, with vertebrate homologs implicated in binding the small GTPase Rac and a GEX-3 Drosophila homolog, HEM2/NAP1/KETTE, that interacts genetically with Rac pathway mutants. Our findings suggest that GEX-2 and GEX-3 may function at cell boundaries to regulate cell migrations and cell shape changes required for proper morphogenesis and development.
Genes Dev. 2002 Mar 1;16(5):620-32. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/42221
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