Project description:High-throughput sequencing of mixed-stage Caenorhabditis elegans small RNAs. total RNA, ~18-26nt RNAs isolated using PAGE, ligation to adapters requires 5' monophosphate and 3' OH Keywords: high-throughput 454 sequencing
Project description:To identify methylated small RNAs in C. elegans, we deep sequenced both β-eliminated and untreated small RNAs isolated from wild type C. elegans. Small RNAs were isolated from larval and adult stage C. elegans and either subjected to β-elimination or no treatment. Small RNA cDNA libraries were sequenced on an Illumina HiSeq instrument, and enrichment or depletion of small RNAs by β-elimination was assessed after library size normalization based on the number of mappable reads in each library.
Project description:Organisms can develop adaptive sequence-specific immunity by reexpressing pathogen-specific small RNAs that guide gene silencing. For example, the C. elegans PIWI-Argonaute/piwi-interacting RNA (piRNA) pathway recruits RNA-dependent RNA polymerase (RdRP) to foreign sequences to amplify a transgenerational small-RNA-induced epigenetic silencing signal (termed RNAe). Here, we provide evidence that, in addition to an adaptive memory of silenced sequences, C. elegans can also develop an opposing adaptive memory of expressed/self-mRNAs. We refer to this mechanism, which can prevent or reverse RNAe, as RNA-induced epigenetic gene activation (RNAa). We show that CSR-1, which engages RdRP-amplified small RNAs complementary to germline-expressed mRNAs, is required for RNAa. We show that a transgene with RNAa activity also exhibits accumulation of cognate CSR-1 small RNAs. Our findings suggest that C. elegans adaptively acquires and maintains a transgenerational CSR-1 memory that recognizes and protects self-mRNAs, allowing piRNAs to recognize foreign sequences innately, without the need for prior exposure.
Project description:To identify methylated small RNAs in C. elegans, we deep sequenced both β-eliminated and untreated small RNAs isolated from wild type C. elegans.
Project description:These datasets profile the expression of small RNAs with 5p monophosphates and 3p hydroxyls (including miRNAs, 21U-RNAs) across C. elegans development and in dauer, glp-4 mutant, and mixed-stage wt worms. These datasets were prepared in the David P. Bartel laboratory using T4 RNA ligase Rnl2(1-249). Keywords: miRNA and 21U-RNA discovery and developmental expression profiling
