TPM2, also named as TMSB, belongs to the tropomyosin family. It binds to actin filaments in muscle and non-muscle cells. TPM2 plays a central role, in association with the troponin complex, in the calcium dependent regulation of vertebrate striated muscle contraction. In non-piamuscle cells, TPM2 is implicated in stabilizing cytoskeleton actin filaments. Defects in TPM2 are the cause of nemaline myopathy type 4 (NEM4) and distal arthrogryposis type 1 (DA1).