The GEX-2 and GEX-3 proteins are required for tissue morphogenesis and cell migrations in C. elegans.
During 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.
Soto
Martha C
MC
Program in Molecular Medicine and Cell Biology, Howard Hughes Medical Institute, University of Massachusetts Cancer Center, Worcester, Massachusetts 01605, USA.
Qadota
Hiroshi
H
Kasuya
Katsuhisa
K
Inoue
Makiko
M
Tsuboi
Daisuke
D
Mello
Craig C
CC
Kaibuchi
Kozo
K
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000254:growth & development*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics; D002451:Cell Compartmentation; D002465:Cell Movement; D017124:Conserved Sequence; D029721:Drosophila Proteins; D017238:Genes, Helminth; D008969:Molecular Sequence Data; D009024:Morphogenesis; D010058:Oviposition / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D020744:rac GTP-Binding Proteins / Q000235:genetics
D048868:Adaptor Proteins, Signal Transducing; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D029721:Drosophila Proteins; C450821:GEX-2 protein, C elegans; C450822:GEX-3 protein, C elegans; C484666:Sra-1 protein, Drosophila; D020744:rac GTP-Binding Proteins