title: Caenorhabditis elegans WASP-interacting protein homologue WIP-1 is involved in morphogenesis through maintenance of WSP-1 protein levels.
abstract: Mammalian WASP and N-WASP are involved in reorganization of the actin cytoskeleton through activation of the Arp2/3 complex and in regulation of cell motility or cell shape changes. In the present study, we identified WASP-interacting protein homologue (WIP)-1 in Caenorhabditis elegans. WIP-1 contains the domains and sequences conserved among mammalian WIP family proteins. Yeast two-hybrid analysis detected a physical interaction between WIP-1 and WSP-1, the sole homologue of WASP/N-WASP in C. elegans. Western analysis of embryo lysates showed that RNA interference (RNAi) treatment for wip-1 decreased levels of WSP-1 protein, and wsp-1(RNAi) treatment decreased levels of WIP-1 protein. However, wsp-1 mRNA levels were not decreased in wip-1(RNAi)-treated embryos, and wip-1 mRNA levels were not decreased in wsp-1(RNAi)-treated embryos. Furthermore, disruption of WIP-1 by RNAi resulted in embryonic lethality with morphologic defects in hypodermal cell migration, a process known as ventral enclosure. This phenotype was similar to that observed in RNAi experiments for wsp-1. Immunostaining showed that WIP-1 was expressed by migrating hypodermal cells, as was WSP-1. This expression during ventral enclosure was reduced in wip-1(RNAi)-treated embryos and wsp-1(RNAi)-treated embryos. Our results suggest that C. elegans WIP-1 may function in hypodermal cell migration during ventral enclosure by maintaining levels of WSP-1.
authors.affiliation: Department of Biochemistry, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Sawa
authors.forename: Tadaomi
authors.initials: T
authors.lastname: Takenawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000254:growth & development / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000502:physiology*; D009363:Neoplasm Proteins; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C; D034622:RNA Interference; D040521:Subcutaneous Tissue / Q000196:embryology; D051300:Wiskott-Aldrich Syndrome Protein Family / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D009363:Neoplasm Proteins; C508564:WIP-1 protein, C elegans; D051300:Wiskott-Aldrich Syndrome Protein Family; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C