Sex-biased expression of microRNAs in Drosophila pseudoobscura

Small RNA sequencing from Drosophila pseudoobscura males and virgin females. All flies were kept at 18ºC on cornmeal based media, with 12 hours light/dark cycles. Adult males and females were collected at age 7 days. We extracted total RNA form samples using TRIzol (Life Technologies) as recommended by the manufacturer. RNA was dissolved in RNase-free water. For small RNA sequencing we used the TruSeq Small RNA Sample Preparation Kit (Illumina) to generate the cDNA library and we selected constructs of sizes 145 to 160 bp in a 6% PAGE gel, and precipitated in ethanol. DNA integrity was checked with TapeStation (Agilent). Samples were sequenced in-house with an Illumina MiSeq sequencing machine.