The PARN deadenylase targets a discrete set of mRNAs for decay and regulates cell motility in mouse myoblasts. Mus musculus

Almost all cellular mRNAs terminate in a 3’ poly(A) tail, the removal of which can induce both translational silencing and mRNA decay. Mammalian cells encode many poly(A)-specific exoribonucleases but their individual roles are poorly understood. Here, we undertook an analysis of the role of PARN deadenylase in mouse myoblasts using global measurements of mRNA decay rates. Our results reveal that a discrete set of mRNAs exhibit altered mRNA decay as a result of PARN depletion and that stabilization is associated with increased poly(A) tail length and translation. We determined that stabilization of mRNAs does not generally result in their increased abundance supporting the idea that mRNA decay is coupled to transcription. Importantly, PARN knockdown has wide ranging effects on gene expression that specifically impact the extracellular matrix and cell migration. Finally, although PARN has its own unique target transcripts it also influences some genes whose expression is modulated by other deadenylases. Overall design: In order to investigate the role of PARN deadenyl on mRNA decay in mouse muscle cells , C2C12 cells were transfected by shRNA knockdown of PARN and treated with actinomycin D to inhibit transcription. Total RNA was isolated from three replicates at 0, 15, 30, 60, 120 and 240 minutes. The CTRL cell line stably transfected with LKO1 vector was described previously (GSE21233).