Caldesmon 1 (CALD1) (CALD1)

Caldesmon 1 (CALD1) is a calcium-binding protein that acts as a key regulator of smooth muscle contraction and non-muscle cell motility by modulating the interaction between actin and myosin [1][2]. It exists in two major isoforms: the high-molecular-weight H-caldesmon, primarily expressed in differentiated smooth muscle cells, and the low-molecular-weight L-caldesmon, found in various non-muscle tissues and proliferating cells [1]. CALD1 functions by binding to actin and tropomyosin, which inhibits the actomyosin ATPase activity and prevents muscle contraction; this inhibition is relieved upon binding with calcium-calmodulin or through phosphorylation by various kinases [1][2]. In the field of oncology, CALD1 is a significant diagnostic biomarker used to identify smooth muscle tumors, such as leiomyosarcomas, and to distinguish them from other spindle cell neoplasms [4]. Furthermore, CALD1 is implicated in cancer progression, where its overexpression is associated with increased cell migration, invasion, and tumor-associated angiogenesis in several malignancies, including gliomas and colorectal cancer [3]. Although there are currently no FDA-approved drugs that directly target CALD1, it remains a subject of intense research as a potential therapeutic target for inhibiting metastasis and managing smooth muscle-related disorders [2][3].

Other names

CDMH-CADL-CADCaldesmonCALD1

Inhibition of actomyosin ATPase activity through binding to actin and tropomyosin filaments [1][2]