title: RNA-Seq of mus musculus
design: We randomly selected a representative mouse serum sample from each of the four groups of mice to detect the microRNAs (miRNAs) and the piwi-interacting RNAs (piRNAs) using the next-generation sequencing platform BGISEQ-500 (BGI, Shenzhen, China) . The clean sequencing tags were annotated using Bowtie2 based on various small RNA databases including miRbase (http://www.mirbase.org/), Rfam (https://rfam.xfam.org/), siRNA (http://web.mit.edu/sirna/), piRNA (https://www.pirnadb.org/), and snoRNA (http://snoopy.med.miyazaki-u.ac.jp). Based on the results of these annotations, the unknown tags were further annotated to predict novel miRNAs using miRDeep and miRA (  and piRNAs using Piano  respectively.