CGC Bibliography Paper 3142

Caenorhabditis elegans SUR-5, a novel but conserved protein, negatively regulates LRT-60 ras activity during vulval induction.

Gu T, Orita S, Han M

Medline:
98336261
Citation:
Molecular and Cellular Biology 18: 4556-4564 1998
Type:
ARTICLE
Genes:
let-23 let-60 lin-3 lin-8 lin-9 lin-10 lin-15 lin-45 mpk-1 sem-5 sur-1 sur-5 unc-119
Abstract:
The let-60 ras gene acts in a signal transduction pathway to control vulval differentiation in Caenorhabditis elegans. By screening suppressors of a dominant negative let-60 ras allele, we isolated three loss-of-function mutations in the sur-5 gene which appear to act as negative regulators of let-60 ras during vulval induction. sur-5 mutations do not cause an obvious mutant phenotype of their own, and they appear to specifically suppress only one of the two groups of let-60 ras dominant negative mutations, suggesting that the gene may be involved in a specific aspect of Ras activation. Consistent with its negative function, overexpressing sur-5 from an extragenic array partially suppresses the Multivulva phenotype of an activated let-60 ras mutation and causes synergistic phenotypes,vith a lin-45 raf mutation. We have cloned sur-5 and shown that it encodes a novel pro tein. We have also identified a potential mammalian SUR-5 homolog that is about 35% identical to the worm protein. SUR-5 also has some sequence similarity to acetyl coenzyme A synthetases and is predicted to contain ATP/GTP and AMP binding sites. Our results suggest that sur-5 gene function may be