HOW(S) RIP-seq in D. melanogaster testes

Held out wings (HOW) is an RNA-binding protein essential for spermatogenesis in Drosophila melanogaster. HOW is a signal transduction and activation of RNA (STAR) protein, these proteins are important post-transcriptional regulators of RNAs. The characteristics of RNA-binding by the conserved short cytoplasmic isoform, HOW(S), are unknown. In vivo RIP-seq identified 121 novel transcripts bound by HOW(S) in spermatogonia, many with signal transduction functions. (A/G/U)CUAAC motifs were enriched in 3'-UTRs and GCG(A/U)G in 5'-UTRs. HOW binds with high-affinity to sites containing the CUAAC motif from lola and hipk mRNAs, but not to GCG(A/U)G 5'-UTR motifs. Overall, this study provides new insight into STAR protein-RNA interactions and potential importance to spermatogenesis. Overall design: In vivo RIP-seq with anti-HA beads from two different genotypes of D. melanogaster testes: 1) nanos-GAL4>UAS-HOW(S)-HA and 2) nanos-GAL4.