title: ROP-1, an RNA quality-control pathway component, affects Caenorhabditis elegans dauer formation.
abstract: Caenorhabditis elegans dauer formation is an alternative larval developmental pathway that the worm can take when environmental conditions become detrimental. Animals can survive several months in this stress-resistant stage and can resume normal development when growth conditions improve. Although the worms integrate a variety of sensory information to commit to dauer formation, it is currently unknown whether they also monitor internal cellular damage. The Ro ribonucleoprotein complex, which was initially described as a human autoantigen, is composed of one major 60-kDa protein, Ro60, that binds to one of four small RNA molecules, designated Y RNAs. Ro60 has been shown to bind mutant 5S rRNA molecules in Xenopus oocytes, suggesting a role for Ro60 in 5S rRNA biogenesis. Analysis of ribosomes from a C. elegans rop-1(-) strain, which is null for the expression of Ro60, demonstrated that they contain a high percentage of mutant 5S rRNA molecules, thereby strengthening the notion of a link between the rop-1 gene product and 5S rRNA quality control. The Ro particle was recently shown to be involved in the resistance of Deinococcus radiodurans to UV irradiation, suggesting a role for the Ro complex in stress resistance. We have studied the role of rop-1 in dauer formation. We present genetic and biochemical evidence that rop-1 interacts with dauer-formation genes and is involved in the regulation of the worms' entry into the dauer stage. Furthermore, we find that the rop-1 gene product undergoes a proteolytic processing step that is regulated by the dauer formation pathway via an aspartic proteinase. These results suggest that the Ro particle may function in an RNA quality-control checkpoint for dauer formation.
authors.affiliation: Biology Department, McGill University, 1205 Dr. Penfield Avenue, Montréal, QC H3A 1B1, Canada.
authors.forename: J C
authors.initials: JC
authors.lastname: Labbé
authors.forename: J
authors.initials: J
authors.lastname: Burgess
authors.forename: L A
authors.initials: LA
authors.lastname: Rokeach
authors.forename: S
authors.initials: S
authors.lastname: Hekimi
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics* / Q000254:growth & development*; D029742:Caenorhabditis elegans Proteins; D004625:Embryo, Nonmammalian / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D005838:Genotype; D015801:Helminth Proteins / Q000235:genetics* / Q000378:metabolism*; D007814:Larva; D015800:Protozoan Proteins / Q000235:genetics* / Q000378:metabolism*; D018510:RNA, Helminth / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; C102095:DAF-7 protein, C elegans; D015801:Helminth Proteins; D015800:Protozoan Proteins; D018510:RNA, Helminth; D016601:RNA-Binding Proteins; D016212:Transforming Growth Factor beta; C065352:rhoptry associated protein, Plasmodium; C107483:DAF-2 protein, C elegans; D011972:Receptor, Insulin