The Caenorhabditis elegans rsd-2 and rsd-6 genes are required for chromosome functions during exposure to unfavorable environments.
In Caenorhabditis elegans, exogenous dsRNA can elicit systemic RNAi, a process that requires the function of many genes. Considering that the activities of many of these genes are also required for normal development, it is surprising that exposure to high concentrations of dsRNA does not elicit adverse consequences to animals. Here, we report inducible phenotypes in attenuated C. elegans strains reared in environments that include nonspecific dsRNA and elevated temperature. Under these conditions, chromosome integrity is compromised in RNAi-defective strains harboring mutations in rsd-2 or rsd-6. Specifically, rsd-2 mutants display defects in transposon silencing, while meiotic chromosome disjunction is affected in rsd-6 mutants. RSD-2 proteins localize to multiple cellular compartments, including the nucleolus and cytoplasmic compartments that, in part, are congruent with calreticulin and HAF-6. We considered that the RNAi defects in rsd-2 mutants might have relevance to membrane-associated functions; however, endomembrane compartmentalization and endocytosis/exocytosis markers in rsd-2 and rsd-6 mutants appear normal. The mutants also possess environmentally sensitive defects in cell-autonomous RNAi elicited from transgene-delivered dsRNAs. Thus, the ultimate functions of rsd-2 and rsd-6 in systemic RNAi are remarkably complex and environmentally responsive.
Han
Wang
W
Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045, USA.
Sundaram
Prema
P
Kenjale
Himanshu
H
Grantham
James
J
Timmons
Lisa
L
D000483:Alleles; D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000187:drug effects / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D002451:Cell Compartmentation / Q000187:drug effects; D002875:Chromosomes / Q000378:metabolism*; D004777:Environment; D041981:Gastrointestinal Tract / Q000187:drug effects; D018628:Gene Dosage / Q000187:drug effects; D017238:Genes, Helminth; D017930:Genes, Reporter; D005854:Germ Cells / Q000187:drug effects; D008565:Membrane Proteins / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D020033:Protein Isoforms / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D034622:RNA Interference / Q000187:drug effects; D012330:RNA, Double-Stranded / Q000494:pharmacology; D013347:Subcellular Fractions / Q000187:drug effects; D019076:Transgenes; D014819:Vitellogenins / Q000378:metabolism
D029742:Caenorhabditis elegans Proteins; D008565:Membrane Proteins; D020033:Protein Isoforms; D012330:RNA, Double-Stranded; C529657:RSD-2 protein, C elegans; C529658:RSD-6 protein, C elegans; C452203:SID-1 protein, C elegans; D014819:Vitellogenins