TXNRD2 and atrial fibrillation: However, independently knocking down the known targets for AF, TrxR1 and TrxR2, did not alter the extent of AF -induced NHK degradation or mimic the ability of AF to promote NHK removal (Supplementary Fig. 8b–e), indicating that AF-induced NHK degradation is not mediated by targeting TrxR1 and TrxR2.