A feedback loop between protein SNRK and circ-SNRK limited the expression abundance of SNRK at a proper level; a bidirectional regulation of hypoxia in protein SNRK via P65 and Caspase 3, respectively, together suggesting that protein SNRK plays a vital role in the regulation of cardiac function post-MI. The gene discussed is SNRK; the disease is myocardial infarction.