Project description:This project defines the transcriptomes of XO (male) and XX (female or mutant pseudo-female) Caenorhabditis nematodes. The data allow the overall composition and sexual regulation of the transcriptome within a single species to be determined. In addition, the five related species studied allow meta-comparisons between them. Because two of the five (C. elegans and C. briggsae) produce a self-fertile XX hermaphrodite, while the XX sex in the remaining three (C. japonica, C. remanei, and C. brenneri) are true females, the data are particularly useful for inferring effects of sexual mode on genome-wide gene expression. L4 larvae and adults were pooled for each sex for five species (C. elegans, C. briggsae, C. japonica, C. brenneri, and C. remanei). Each of these 10 species-sex combinations was replicated three times, for a total of 30 samples.
Project description:This project defines the transcriptomes of XO (male) and XX (female or mutant pseudo-female) Caenorhabditis nematodes. The data allow the overall composition and sexual regulation of the transcriptome within a single species to be determined. In addition, the five related species studied allow meta-comparisons between them. Because two of the five (C. elegans and C. briggsae) produce a self-fertile XX hermaphrodite, while the XX sex in the remaining three (C. japonica, C. remanei, and C. brenneri) are true females, the data are particularly useful for inferring effects of sexual mode on genome-wide gene expression.
Project description:The nematode Caenorhabditis elegans contains each of the broad classes of eukaryotic small RNAs, including microRNAs (miRNAs), endogenous small-interfering RNAs (endo-siRNAs) and piwi-interacting RNAs (piRNAs). To better understand the evolution of these regulatory RNAs, we deep sequenced small RNAs from C. elegans and three closely related nematodes: C. briggsae, C. remanei and C. brenneri. The results reveal a fluid landscape of small RNA pathways with essentially no conservation of individual sequences aside from a subset of miRNAs. We identified 52 miRNA families that are conserved in each of the four species as well as numerous miRNAs that are species specific or shared between only two or three species. Despite a lack of conservation of individual piRNAs and siRNAs many of the features of each pathway, including genomic distribution, are conserved. We show that in each species, 26G siRNAs trigger stage-specific secondary siRNA formation. We also observe that piRNAs trigger siRNA formation from targets containing up to three mismatches in each species. Finally, we show that nematodes produce two distinct sex-specific classes of piRNAs, suggesting different roles for piRNAs in male and female germlines. Sequencing small RNAs from four Caenorhabditis species: C. elegans, C. briggsae, C. remanei and C. brenneri