Anti-MyHC-IIb antibodies are protein reagents that detect specific antigens. The MyHC-IIb antigen is another term for the human protein myosin heavy chain 4, encoded by the MYH4 gene. The protein is known to function in muscle contraction, among other biological roles. Canonically, it has an amino acid length of 1939 residues and a mass of 223.1 kilodaltons. Its subcellular localization is in the cytoplasm and it is expressed in the heart muscle and skeletal muscle. The MyHC-IIb protein is a member of the Myosin protein family. Other alias names for MyHC-IIb include MYH2B, MyHC-2B, and MyHC-IIb.