design: cDNA libraries were prepared for sequencing on the HiSeq4000. Alignments to Rattus norvegicus genome (Rnor v6.0) used STAR (v2.6.1a) and were annotated with Ensembl v95. Genes were reannotated using BiomaRt and Ensembl (v99). The count data was transformed to 2log-counts per million (logCPM) using voom, which estimates the mean-variance relationship.