Caldesmon was identified as a Ca2+/Calmodulin-binding protein with molecular weight of 120-150kDa high molecular weight Caldesmon (H-Caldesmon) and 70-80kDa low molecular weight (L-Caldesmon). H-Caldesmon (isoform 1) which is an actin, myosin, tropomyosin, and calmodulin-binding protein, is expressed in differentiated contractile smooth muscle cells (SMC) while L-Caldesmon (isoforms 2, 3, 4 and 5) is most abundant in non-muscle tissue and cells. Neither of the two variants has been detected in skeletal muscle or heart. As such, H‐Caldesmon is a specific marker for SMC and could aid in the differential diagnosis of tumors with a SMC component (e.g. leiomyosarcoma) from other tumors with smooth muscle‐like differentiation e.g. myofibroblastic tumors. L-Caldesmon may play an important function in motile processes such as secretion and organelle movement. This antibody recognizes only the 150kDa variant H-Caldesmon, labels smooth muscle and tumors of smooth muscle.
Clone
MD334R
Isotype
IgG
Host species
Rabbit
Species Reactivity
Human
Cellular Localization
Cytoplasm
Positive Control
Smooth muscle, uterus, leiomyoma
Applications
IHC
Intended Use
Research Use Only