Synaptophysin-like 2 (MG29) (MG29)

Synaptophysin-like 2 (MG29), commonly known as Mitsugumin 29, is a muscle-specific transmembrane protein that belongs to the synaptophysin family. It is primarily localized to the triad junction in skeletal muscle, where it plays a vital role in the structural organization and maturation of the transverse tubule (T-tubule) network. MG29 is essential for maintaining intracellular calcium homeostasis and efficient excitation-contraction (E-C) coupling by facilitating the functional interaction between the dihydropyridine receptor (DHPR) and the ryanodine receptor (RyR1). Additionally, it regulates store-operated calcium entry (SOCE) through its interaction with TRPC3 and TRPC4 channels. Reduced expression of MG29 has been linked to muscle fatigue, sarcopenia (age-related muscle loss), and the progression of muscular dystrophies. In the context of heart failure, MG29 induction may serve as a compensatory mechanism to stabilize T-tubule architecture. While no FDA-approved drugs currently target MG29, it is being explored as a therapeutic target for muscle-wasting diseases and metabolic disorders like diabetes through protein and gene therapy approaches.

Other names

Mitsugumin 29MG29SYPL2Synaptophysin-like protein 2

Stabilization of T-tubule architecture and regulation of calcium signaling through interaction with RyR1, DHPR, and TRPC channels.