Role of XRN2 ribonucleolytic activity in RNA metabolism

We analysed the effect of depriving the human cell of the catalytic activity of the nuclear 5' to 3' exoribonuclease XRN2. Catalytic amino acids in this protein had been defined previously, so it was possible to design a mutated catalytically inactive form of the protein (XRN2D233A-D235A) (PMID: 19194460). We created 293 Flp-In T-REx stable cell lines that induciby silence endogenous XRN2, and concomitantly express wild-type or inactive XRN2 in fusion with EGFP at the C-terminus. Thus, complementation of silencing of endogenous XRN2 with the expression of mutant version of the protein allows to directly link potential phenotypes with the lack of XRN2 enzymatic activity. To this end we isolated total RNA from tetracycline-treated cells, depleted it from rRNA and conducted strand-specific deep sequencing. Overall design: 6 samples were analysed. 3 replicates of control cells (endogenous copy of XRN2 gene is silenced and catalytically active exogenous XRN2-EGFP is expressed) and 3 replicates of cells deprived of XRN2 ribonucleolytic activity (endogenous copy of XRN2 gene is silenced and catalytically inactive exogenous XRN2(D233AD235A)-EGFP is expressed)