title: Caenorhabditis elegans LET-502 is related to Rho-binding kinases and human myotonic dystrophy kinase and interacts genetically with a homolog of the regulatory subunit of smooth muscle myosin phosphatase to affect cell shape.
abstract: We have identified two genes associated with the hypodermal cell shape changes that occur during elongation of the Caenorhabditis elegans embryo. The first gene, called let-502, encodes a protein with high similarity to Rho-binding Ser/Thr kinases and to human myotonic dystrophy kinase (DM-kinase). Strong mutations in let-502 block embryonic elongation, and let-502 reporter constructs are expressed in hypodermal cells at the elongation stage of development. The second gene, mel-11, was identified by mutations that act as extragenic suppressors of let-502. mel-11 encodes a protein similar to the 110- to 133-kD regulatory subunits of vertebrate smooth muscle myosin-associated phosphatase (PP-1M). We suggest that the LET-502 kinase and the MEL-11 phosphatase subunit act in a pathway linking a signal generated by the small GTP-binding protein Rho to a myosin-based hypodermal contractile system that drives embryonic elongation. LET-502 may directly regulate the activity of the MEL-11 containing phosphatase complex and the similarity between LET-502 and DM-kinase suggests a similar function for DM-kinase.
authors.affiliation: University of Calgary, Department of Medical Biochemistry, Alberta, Canada. wissmann@acs.ucalgary.ca
authors.forename: A
authors.initials: A
authors.lastname: Wissmann
authors.forename: J
authors.initials: J
authors.lastname: Ingles
authors.forename: J D
authors.initials: JD
authors.lastname: McGhee
authors.forename: P E
authors.initials: PE
authors.lastname: Mains
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000196:embryology / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D048429:Cell Size; D003001:Cloning, Molecular; D019204:GTP-Binding Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D016153:Genes, Suppressor; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D043263:Myosin-Light-Chain Phosphatase; D065636:Myotonin-Protein Kinase; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D054460:rho-Associated Kinases
chemical_list: D029742:Caenorhabditis elegans Proteins; C585517:DMPK protein, human; D047908:Intracellular Signaling Peptides and Proteins; C515856:LET-502 protein, C elegans; D065636:Myotonin-Protein Kinase; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D010749:Phosphoprotein Phosphatases; D043263:Myosin-Light-Chain Phosphatase; D019204:GTP-Binding Proteins