ATP2A2 and hydrops fetalis: In HF, SERCA2 can undergo either ‘stimulatory’ modification by glutathionylation on C674 (Adachi et al., 2004) and/or SUMOylation on K480 and K585 (Kho et al., 2011), and ‘inhibitory’ acetylation of K492 (Gorski et al., 2019).