title: Genetic characterization of smg-8 mutants reveals no role in C. elegans nonsense mediated decay.
abstract: The nonsense mediated decay (NMD) pathway degrades mRNAs bearing premature translation termination codons. In mammals, SMG-8 has been implicated in the NMD pathway, in part by its association with SMG-1 kinase. Here we use four independent assays to show that C. elegans smg-8 is not required to degrade nonsense-containing mRNAs. We examine the genetic requirement for smg-8 to destabilize the endogenous, natural NMD targets produced by alternative splicing of rpl-7a and rpl-12. We test smg-8 for degradation of the endogenous, NMD target generated by unc-54(r293), which lacks a normal polyadenylation site. We probe the effect of smg-8 on the exogenous NMD target produced by myo-3::GFP, which carries a long 3' untranslated region that destabilizes mRNAs. None of these known NMD targets is influenced by smg-8 mutations. In addition, smg-8 animals lack classical Smg mutant phenotypes such as a reduced brood size or abnormal vulva. We conclude that smg-8 is unlikely to encode a component critical for NMD.
authors.affiliation: Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachussetts, United States of America.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Rosains
authors.forename: Susan E
authors.initials: SE
authors.lastname: Mango
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D023061:Gene Order; D017930:Genes, Reporter; D009154:Mutation; D059365:Nonsense Mediated mRNA Decay; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D012333:RNA, Messenger; D012269:Ribosomal Proteins; C581743:SMG-8 protein, C elegans