A starvation-induced noncoding RNA modulates expression of Dicer-regulated genes.
Although much has been learned about short noncoding RNAs, long noncoding transcripts are largely uncharacterized. Here, we describe Caenorhabditis elegans rncs-1, a highly base-paired, 800-nucleotide noncoding RNA expressed in hypodermis and intestine. Transcription of rncs-1 is modulated in response to food supply. Although highly double-stranded, we show that rncs-1 RNA is not a substrate for Dicer because of branched structures at its termini. However, rncs-1 RNA inhibits Dicer cleavage of a second dsRNA in vitro, presumably by competition. We validate this observation in vivo by demonstrating that mRNA levels of several Dicer-regulated genes vary with changes in rncs-1 expression. Certain viruses express dsRNA to compete with cellular dsRNA-mediated pathways, and our data suggest that rncs-1 provides a cellular correlate of this phenomenon.
Hellwig
Sabine
S
Department of Biochemistry and Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112, USA.
Bass
Brenda L
BL
D000818:Animals; D017173:Caenorhabditis elegans / Q000201:enzymology* / Q000235:genetics*; D005508:Food Deprivation; D005786:Gene Expression Regulation; D017238:Genes, Helminth; D016678:Genome; D007413:Intestinal Mucosa / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D034741:RNA, Small Interfering / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics*; D043244:Ribonuclease III / Q000378:metabolism*; D040521:Subcutaneous Tissue / Q000378:metabolism; D014158:Transcription, Genetic
D034741:RNA, Small Interfering; D022661:RNA, Untranslated; D043244:Ribonuclease III