GSE13081
An epigenetic role for maternally inherited piRNAs in transposon silencing
In plants and mammals, small RNAs indirectly mediate epigenetic inheritance  by specifying cytosine methylation.  Here, we find that small RNAs  themselves serve as vectors for epigenetic information.  Crosses between  Drosophila strains that differ in the presence of a particular transposon  can produce sterile progeny, a phenomenon called hybrid dysgenesis.  This  phenotype manifests itself only if the transposon is paternally inherited,  suggesting maternal transmission of a factor that maintains fertility. In  both P- and I-element-mediated hybrid-dysgenesis models, daughters show a  markedly different content of piRNAs targeting each element, depending upon  its parent of origin.  Such differences persist from fertilization through  adulthood.  This indicates that maternally deposited piRNAs are crucial for  mounting an effective silencing response and that a lack of maternal piRNA  inheritance underlies hybrid dysgenesis. Mappers table contains all of the sequences in our libraries that map to the drosophila genome (release 5) Nonmappers table contains all of the sequences in our libraries that do not map to the drosophila genome(release 5) Overall design: 15 small RNA libraries were generated from total RNA of Drosophila melanogaster ovarian and embryo tissues and analyzed for this study