let-60, a gene that specifies cell fates during C. elegans vulval induction, encodes a ras protein.
Genetic analysis previously suggested that the let-60 gene controls the switch between vulval and hypodermal cell fates during C. elegans vulval induction. We have cloned the let-60 gene, and shown that it encodes a gene product identical in 84% of its first 164 amino acids to ras gene products from other vertebrate and invertebrate species. This conservation suggests that the let-60 product contains all the biochemical functions of ras proteins. Extrachromosomal arrays of let-60 ras DNA cause cell-type misspecification (extra vulval fates) phenotypically opposite to that caused by let-60 ras loss-of-function mutations (no vulval fates), and suppress the vulvaless phenotype of mutations in two other genes necessary for vulval induction. Thus, the level and pattern of let-60 ras expression may be under strict regulation; increase in let-60 ras activity bypasses or reduces the need for upstream genes in the vulval induction pathway.
Han
M
M
Howard Hughes Medical Institute.
Sternberg
P W
PW
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002107:Caenorhabditis / Q000196:embryology / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D003001:Cloning, Molecular; D003360:Cosmids; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D012734:Disorders of Sex Development; D004625:Embryo, Nonmammalian; D005260:Female; D011905:Genes, ras; D015801:Helminth Proteins / Q000235:genetics*; D008954:Models, Biological; D008969:Molecular Sequence Data; D010957:Plasmids; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D015398:Signal Transduction; D014158:Transcription, Genetic; D014844:Vulva / Q000196:embryology; D018631:ras Proteins
D029742:Caenorhabditis elegans Proteins; D015801:Helminth Proteins; C066646:let-60 protein, C elegans; D004247:DNA; D018631:ras Proteins