| 背景信息 |
Caldesmon 1 (CALD1) is a multifunctional actin- and myosin-binding protein that serves as a key regulator of actomyosin interactions in both smooth muscle and nonmuscle cells. It functions primarily by inhibiting actin-tropomyosin-activated myosin MgATPase activity, a process modulated by calcium-calmodulin binding and phosphorylation by kinases such as PAK. CALD1 exists in high and low molecular weight isoforms, which are essential for cytoskeleton stabilization, cell migration, and mitosis. The protein features distinct domains for binding myosin, calmodulin, actin, and tropomyosin, allowing it to integrate various signaling inputs to control cellular motility. Clinically, CALD1 is associated with smooth muscle tumors such as adenomyoma and cellular leiomyoma. In oncology, its upregulation serves as a biomarker for certain solid tumors, where it can influence invasion and metastasis through the regulation of podosomes and invadopodia. |