Tripartite motif-containing protein 72 (MG53) (TRIM72)

Tripartite motif-containing protein 72 (TRIM72), commonly known as MG53, is a muscle-specific protein that serves as an essential component of the cell's intrinsic plasma membrane repair machinery. It is primarily expressed in skeletal and cardiac muscle, where it acts as a sensor for membrane disruptions, rapidly translocating to injury sites to facilitate vesicle-mediated resealing and maintain cellular integrity. Beyond its structural role, MG53 functions as an E3 ubiquitin ligase and a secreted myokine, modulating key signaling pathways such as PI3K/Akt for cell survival and NF-κB for inflammation. While MG53 offers significant therapeutic potential for treating acute injuries like myocardial infarction, muscular dystrophy, and acute lung injury, its chronic overexpression is associated with the development of insulin resistance and metabolic syndrome due to its role in degrading insulin receptor substrate-1 (IRS-1). Consequently, MG53 is considered a double-edged sword in regenerative medicine, with current drug development focusing on recombinant human MG53 (rhMG53) as a treatment for various tissue injuries.

Other names

Mitsugumin-53MG53TRIM72

MG53 facilitates plasma membrane repair by sensing membrane disruptions and recruiting intracellular vesicles to the injury site through interaction with phosphatidylserine. It also acts as an E3 ubiquitin ligase that mediates the degradation of insulin receptor substrate-1 (IRS-1) and the insulin receptor, thereby negatively regulating insulin signaling. Additionally, it activates survival pathways such as PI3K/Akt and ERK1/2 and inhibits pro-inflammatory signaling through the NF-κB and NLRP3 inflammasome pathways.