Project description:We performed RNA-seq to quantify gene expression changes in adult worms upon knockdown of transcription factor unc-62/Homothorax. unc-62 is a developmental regulator that binds proximal to age-regulated transcripts and modulates lifespan. In the intestine (in which tissue-specific unc-62 knockdown increases lifespan), we identify multiple effects of unc-62 knockdown linked to extension of longevity. First, unc-62 RNAi decreases the expression of yolk proteins (vitellogenins) that aggregate in the body cavity and become toxic in old age. Second, unc-62 RNAi results in a broad increase in expression of intestinal genes that typically decrease expression with age, suggesting that unc-62 activity balances intestinal resource allocation between yolk protein expression and fertility on the one hand and somatic functions on the other. mRNA profiling by Illumina HiSeq of 3 biological replicates of day 4 adult Caenorhabditis elegans that were fed either control or unc-62 RNAi beginning at day 1 of adulthood.
Project description:small RNA gene expression profiles of C. elegans in 4 age groups. The RNA-seq data comprise 4 age groups (1, 5, 10 and 20 days after L4). Jena Centre for Systems Biology of Ageing - JenAge (www.jenage.de)
Project description:The double-stranded RNA-binding protein Staufen has been implicated in various posttranscriptional gene regulatory processes. Here, we demonstrate that the Caenorhabditis elegans homolog of Staufen, STAU-1, functionally interacts with microRNAs. Loss-of-function mutations of stau-1 significantly suppress phenotypes of let-7 family microRNA mutants, a hypomorphic allele of dicer and a lsy-6 microRNA partial loss-of-function mutant. Furthermore, STAU-1 modulates the activity of lin-14, a target of lin-4 and let-7 family microRNAs, and this modulation is abolished when the 3' untranslated region of lin-14 is removed. Deep sequencing of small RNA cDNA libraries reveals no dramatic change in the levels of microRNAs, or other small RNA populations between wild-type and stau-1 mutants, with the exception of certain endogenous siRNAs in the WAGO pathway. The modulation of microRNA activity by STAU-1 does not seem to be associated with the previously reported enhanced exogenous RNAi (Eri) phenotype of stau-1 mutants, since eri-1 exhibits the opposite effect on microRNA activity. Altogether, our results suggest that STAU-1 negatively modulates microRNA activity downstream of biogenesis, possibly by competing with microRNAs for binding on the 3' untranslated region of target mRNAs
