Project description:RNAs associating with PIWI proteins were Immunoisolated from BmN4 cells. Sequence libraries were generated with NEBNext Small RNA Library Prep Set for Illumina(NEB). Libraries were sequenced using Illumina MiSeq (single-end, 51 cycles).

2020-09-02 | GSE150444 | GEO

MicroRNAs of Bombyx mori identified by Solexa sequencing

Project description:Background: MicroRNA (miRNA) and other small regulatory RNAs contribute to the modulation of a large number of cellular processes. We sequenced three total RNA libraries prepared from the whole body, and the anterior and posterior silk glands of Bombyx mori, with a view to expanding the repertoire of silkworm miRNAs and exploring transcriptional differences in miRNAs between segments of the silk gland. Results: With the aid of large-scale Solexa sequencing technology, we validated 244 unique miRNA genes, including 191 novel and 53 previously reported genes, corresponding to 309 loci in the silkworm genome. Interestingly, 24 unique miRNAs were widely conserved from invertebrates to vertebrates; 12 unique ones were limited to invertebrates and 33 were confined to insects; whereas the majority of the newly identified miRNAs were silkworm-specific. We identified 21 clusters and 42 paralogs of miRNAs in the silkworm genome. However, sequence tags showed that paralogs or clusters are not prerequisites for coordinated transcription and accumulation. The majority of silkworm-specific miRNAs are located in transposable elements, and display significant differences in abundance between the anterior and posterior silk glands. Conclusions: Conservative analysis revealed that miRNAs serve as phylogenetic markers and function in evolutionary signaling. The newly identified miRNAs greatly enriched the repertoire of insect miRNAs, and provide insights into miRNA evolution, biogenesis, and expression in insects. The differential expression of miRNAs in the anterior and posterior silk glands supports their involvement as new layers in the regulation of the silkworm silk gland.

2010-02-01 | GSE17965 | GEO

MicroRNAs of Bombyx mori identified by Solexa sequencing

2010-02-01 | E-GEOD-17965 | biostudies-arrayexpress

High throughput sequencing of Siwi and BmAGO3 associated piRNAs from Bombyx mori BmN4 cells

Project description:In germ cells, piRNAs are amplified through the Ping-Pong cycle that depends on reciprocal Slicer-mediated target RNA cleavage by two PIWI members. A germ-specific DEAD-box protein Vasa is required for the process. However, Vasa’s function is poorly understood. Here, we show that target RNAs cleaved by a Bombyx mori (silkworm) PIWI, Siwi, remain to be bound with the protein upon cleavage, but are released in the presence of Vasa in B. mori (BmVasa) and ATP. Under normal conditions, BmVasa co-purifies with Siwi, but not with second B. mori PIWI BmAgo3. However, when BmVasa loses the ATP-binding and RNA-unwinding activities, BmVasa avidly associates with Siwi and BmAgo3, which contains transposon transcripts predominantly in sense orientation, the sources of BmAgo3-piRNAs. Without BmVasa, BmAgo3 is devoid of piRNAs. Thus, BmVasa actively releases target RNAs from Siwi, upon its cleavage, to urge BmAgo3-piRNA complex formation in the Ping-Pong cycle, enabling continuous supply of piRNAs in germ cells.

2014-12-31 | GSE58221 | GEO

Bombyx mori strain:BmN-4

Project description:mRNA sequences of silkworm cultured cells with adipocyte differentiation

| PRJDB5377 | ENA

High throughput sequencing of Siwi associated piRNAs from Bombyx mori BmN4 cells

2021-02-01 | GSE161405 | GEO