question: What is the biological role of SERCA2 SUMOylation in cardiac physiology and pathophysiology, such as in heart failure?
answer: Recently, the impact of small ubiquitin-related modifier 1 (SUMO-1) on the regulation and preservation of sarcoplasmic reticulum calcium adenosine triphosphatase (SERCA2a) function was discovered. The small ubiquitin-related modifier (SUMO) can be conjugated to lysine residues of target proteins, and is involved in many cellular processes. SERCA2a is SUMOylated at lysines 480 and 585 and this SUMOylation is essential for preserving SERCA2a ATPase activity and stability in mouse and human cells. The levels of SUMO1 and the SUMOylation of SERCA2a itself were greatly reduced in failing hearts. SUMO-1 gene transfer improved cardiac function supporting the critical role of SUMO-1 in SERCA2a function and underlining the therapeutic potential of SUMO-1 for HF patients.