title: Deficiency of Caenorhabditis elegans RecQ5 homologue reduces life span and increases sensitivity to ionizing radiation.
abstract: Gene expression and RNA interference phenotypes were investigated for a Caenorhabditis elegans homologue (Ce-RCQ-5) of human RecQ5 protein. Expression of the mRNA was observed by in situ hybridization from earliest embryogenesis and gradually decreased during late embryogenesis. Ce-RCQ-5 was immuno-localized in the nuclei of embryos, germ cells, and oocytes and also in the nuclei of various somatic cells of larvae and adults. Despite ubiquitous expression in postembryonic cells, RCQ-5 protein expression was highest in intestinal cells, which was confirmed by tagging the gene expression with green fluorescence protein. When endogenous Ce-rcq-5 gene expression was inhibited by RNA interference, no clear phenotypes were observed during development. However, C. elegans life span was reduced by 37% due to RNA interference of rcq-5 gene, suggesting its possible role in maintenance of genomic stability, as has been ascribed to other RecQ family DNA helicases. In addition, C. elegans became significantly more sensitive to ionizing radiation after inhibition of rcq-5 gene expression, indicating an involvement of C. elegans RCQ-5 in a cellular response to DNA damage, possibly in DNA repair.
authors.affiliation: Department of Biochemistry, College of Science, Yonsei University, 120-749, Seoul, South Korea.
authors.forename: Yun Seong
authors.initials: YS
authors.lastname: Jeong
authors.forename: Yool le
authors.initials: Yl
authors.lastname: Kang
authors.forename: Ki Ho
authors.initials: KH
authors.lastname: Lim
authors.forename: Myon Hee
authors.initials: MH
authors.lastname: Lee
authors.forename: Jiyeung
authors.initials: J
authors.lastname: Lee
authors.forename: Hyeon Sook
authors.initials: HS
authors.lastname: Koo
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics; D004265:DNA Helicases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000276:immunology; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000528:radiation effects*; D018507:Gene Expression Regulation, Developmental; D015723:Gene Library; D042822:Genomic Instability; D049452:Green Fluorescent Proteins; D007074:Immunoglobulin G / Q000276:immunology; D017403:In Situ Hybridization; D007814:Larva; D008164:Luminescent Proteins / Q000378:metabolism; D051379:Mice; D009154:Mutation; D034622:RNA Interference; D015347:RNA Probes; D034741:RNA, Small Interfering / Q000494:pharmacology*; D011839:Radiation, Ionizing; D053484:RecQ Helicases
chemical_list: D007074:Immunoglobulin G; D008164:Luminescent Proteins; C506732:RECQL5 protein, human; D015347:RNA Probes; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins; D004265:DNA Helicases; D053484:RecQ Helicases