Transgelin belongs to the calponin family, whose members have an N-terminal calponin homology domain (CH) and a C-terminal calponin-like repeat. Transgelin (also known as SM22) is an actin binding protein localised to the cytoskeletal apparatus []. Transgelin is required in agonist-induced smooth muscle contraction and is involved in cell migration [, ]. It has tumour suppressive functions in certain cells [, ]. Closely related to transgelin is transgelin-3 (TAGLN3), also known as neuronal protein NP25 []or NP22 []. It was identified as a neuron-specific protein and may have a role in the regulation of neurite growth [].