Effect of Nbr on the length of piRNAs and endo-siRNAs in Drosophila

nbr/CG9247 gene regulates the length of a subset of miRNAs. It is not clear whether Nbr affects the length of other classes of small RNAs, such as piRNAs and endo-siRNAs. To address this, we compared small RNA population in wild-type, Df(2L)BSC312/+, nbr null (nbrf02257/Df(2L)BSC312), (nbr null; pCaSper-nbr (WT)), and (nbr null; pCaSper-nbr (D435A,E437A)). This approach revealed that, in addition to miRNAs, piRNAs and endo-siRNAs were also affected in their length in nbr null and nbr null; pCaSper-nbr (D435A,E437A). Overall design: 4-7d ovaries were dissected in PBS, and 40ug total RNA was prepared from wild-type, Df(2L)BSC312/+, nbr null (nbrf02257/Df(2L)BSC312), (nbr null; pCaSper-nbr (WT)), and (nbr null; pCaSper-nbr (D435A,E437A)), using Trizol Reagent (#15596-018, Life Technologies, Carlsbad, CA) following the manufacturer''s protocol. The small RNAs between ~16 to ~29 nt in size were purified from 15% TBE-urea gel (#EC6885BOX, Life Technologies, Carlsbad, CA). Small RNA libraries were prepared using Illumina''s TruSeq small RNA sample preparation kit (#RS-200-0012, Illumina, Inc. San Diego, CA), following the manufacturer''s protocol The libraries were sequenced on HiSeq2000 platform (Illumina).