title: A MAP kinase homolog, mpk-1, is involved in ras-mediated induction of vulval cell fates in Caenorhabditis elegans.
abstract: During development of the Caenorhabditis elegans hermaphrodite, the gonadal anchor cell induces nearby Pn.p cells to adopt vulval fates. The response to this signal is mediated by a receptor tyrosine kinase signal transduction pathway that has been remarkably well conserved during metazoan evolution. Because mitogen-activated protein (MAP) kinases are activated by receptor tyrosine kinase pathways in vertebrate cells, we hypothesized that C. elegans MAP kinase homologs may play a role in vulval induction. Two C. elegans MAP kinase genes, mpk-1 and mpk-2 (mpk, MAP kinase), were cloned using degenerate oligonucleotide primers and PCR amplification; in parallel, genes involved in vulval induction were identified by screening for mutations that suppress the vulval defects caused by an activated let-60 ras gene. One such suppressor mutation is an allele of mpk-1. We used a new type of mosaic analysis to show that mpk-1 acts cell autonomously in the Pn.p cells. Our results show that mpk-1 plays an important functional role as an activator in ras-mediated cell signaling in vivo.
authors.affiliation: Department of Developmental Biology, Stanford University Medical Center, California 94305.
authors.forename: M R
authors.initials: MR
authors.lastname: Lackner
authors.forename: K
authors.initials: K
authors.lastname: Kornfeld
authors.forename: L M
authors.initials: LM
authors.lastname: Miller
authors.forename: H R
authors.initials: HR
authors.lastname: Horvitz
authors.forename: S K
authors.initials: SK
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics; D029742:Caenorhabditis elegans Proteins; D018076:DNA, Complementary; D004627:Embryonic Induction / Q000235:genetics; D005260:Female; D011905:Genes, ras; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1; D008969:Molecular Sequence Data; D009030:Mosaicism; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014844:Vulva / Q000166:cytology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D018076:DNA, Complementary; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D019950:Mitogen-Activated Protein Kinase 1; C085697:mpk-1 protein, C elegans