title: The PLEXIN PLX-2 and the ephrin EFN-4 have distinct roles in MAB-20/Semaphorin 2A signaling in Caenorhabditis elegans morphogenesis.
abstract: Semaphorins are extracellular proteins that regulate axon guidance and morphogenesis by interacting with a variety of cell surface receptors. Most semaphorins interact with plexin-containing receptor complexes, although some interact with non-plexin receptors. Class 2 semaphorins are secreted molecules that control axon guidance and epidermal morphogenesis in Drosophila and Caenorhabditis elegans. We show that the C. elegans class 2 semaphorin MAB-20 binds the plexin PLX-2. plx-2 mutations enhance the phenotypes of hypomorphic mab-20 alleles but not those of mab-20 null alleles, indicating that plx-2 and mab-20 act in a common pathway. Both mab-20 and plx-2 mutations affect epidermal morphogenesis during embryonic and in postembryonic development. In both contexts, plx-2 null mutant phenotypes are much less severe than mab-20 null phenotypes, indicating that PLX-2 is not essential for MAB-20 signaling. Mutations in the ephrin efn-4 do not synergize with mab-20, indicating that EFN-4 may act in MAB-20 signaling. EFN-4 and PLX-2 are coexpressed in the late embryonic epidermis where they play redundant roles in MAB-20-dependent cell sorting.
authors.affiliation: Division of Biological Science, Nagoya University Graduate School of Science, Nagoya, Japan.
authors.forename: Fumi
authors.initials: F
authors.lastname: Nakao
authors.forename: Martin L
authors.initials: ML
authors.lastname: Hudson
authors.forename: Motoshi
authors.initials: M
authors.lastname: Suzuki
authors.forename: Zachary
authors.initials: Z
authors.lastname: Peckler
authors.forename: Rie
authors.initials: R
authors.lastname: Kurokawa
authors.forename: Zhicen
authors.initials: Z
authors.lastname: Liu
authors.forename: Keiko
authors.initials: K
authors.lastname: Gengyo-Ando
authors.forename: Akira
authors.initials: A
authors.lastname: Nukazuka
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujii
authors.forename: Fumikazu
authors.initials: F
authors.lastname: Suto
authors.forename: Yukimasa
authors.initials: Y
authors.lastname: Shibata
authors.forename: Go
authors.initials: G
authors.lastname: Shioi
authors.forename: Hajime
authors.initials: H
authors.lastname: Fujisawa
authors.forename: Shohei
authors.initials: S
authors.lastname: Mitani
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Chisholm
authors.forename: Shin
authors.initials: S
authors.lastname: Takagi
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism* / Q000502:physiology; D015815:Cell Adhesion Molecules / Q000502:physiology*; D036385:Ephrin-A4 / Q000502:physiology*; D008565:Membrane Proteins / Q000378:metabolism*; D009024:Morphogenesis; D009419:Nerve Tissue Proteins / Q000378:metabolism* / Q000502:physiology*; D039961:Semaphorins / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029742:Caenorhabditis elegans Proteins; D015815:Cell Adhesion Molecules; D036385:Ephrin-A4; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D039961:Semaphorins; C405025:mab-20 protein, C elegans; C091529:plexin