Caldesmon150, caldesmon77 and skeletal muscle troponin T share a common antigenic determinant

Abstract
Caldesmon and troponin are known to control actin-myosin interaction in smooth and striated muscle. We showed that polyclonal antibodies to smooth muscle caldesmon150 cross-react with non-muscle caldesmon77 and with skeletal muscle troponin T. The epitope recognized by caldesmon antibodies is located in the CB 2 peptide [residues 71–151] of troponin T. It is supposed that the observed cross-reactivity is due to the common structure of the tropomyosin-binding site of caldesmon and troponin T.