title: The maintenance of neuromuscular function requires UBC-25 in Caenorhabditis elegans.
abstract: Caenorhabditis elegans gene ubc-25 encodes a novel type of an E2 ubiquitin transferase domain (UBCc) protein, which is highly conserved in multicellular animals, but which is not present in the genomes of fungi or plants. To identify the cellular localization of UBC-25 during the development of C. elegans, we used a ubc-25::gfp reporter gene construct. These experiments showed that ubc-25 expression starts during embryogenesis and that it is restricted to neurons and muscle cells in all later stages of development as well as in adult animals. RNA interference with ubc-25 caused late-onset paralysis of most muscular functions such as locomotion, egg laying, and defecation. We therefore propose that ubc-25 in C. elegans is required for the maintenance (homeostasis) of neuromuscular functions by contributing to a tissue specific protein modification pathway, and we speculate that the adult onset phenotype results from the accumulation of target proteins which fail to be degraded.
authors.affiliation: Third Department of Zoology--Developmental Biology, Georg-August University, Göttingen, Humboldtallee 34 A, Göttingen D-37073, Germany. eschulz@gwdg.de
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Schulze
authors.forename: Maria E
authors.initials: ME
authors.lastname: Altmann
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Adham
authors.forename: Bettina
authors.initials: B
authors.lastname: Schulze
authors.forename: Stephan
authors.initials: S
authors.lastname: Fröde
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Engel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000254:growth & development / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D005260:Female; D049452:Green Fluorescent Proteins; D006706:Homeostasis; D008025:Ligases / Q000737:chemistry; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D008297:Male; D008969:Molecular Sequence Data; D032342:Muscle Cells / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010243:Paralysis / Q000209:etiology; D010641:Phenotype; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000032:analysis; D016415:Sequence Alignment; D014452:Ubiquitins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; C475157:UBC-25 protein, C elegans; D014452:Ubiquitins; D049452:Green Fluorescent Proteins; D008025:Ligases