CDH-15 (Cadherin 15; also M-cadherin, Muscle cadherin and Cadherin-14) is a 125-127kD atypical member of the classical cadherin family, cadherin superfamily of molecules. It is expressed by muscle satellite cells, cells of the embryonic myotome, and hematopoietic bone marrow stem cells. CDH-15 appears to bind homotypically in trans, thus allowing for the identification and subsequent fusion of myoblast precursors, particularly those in slow-twitch (or red fiber) muscles. This is accompanied by a downregulation of mitochondrial induced apoptosis. Mouse CDH-15 is synthesized as a 784 amino acid (aa) preproprecursor. It contains a 21aa signal sequence, a 38aa propeptide, and a 725aa mature region. The mature region is expressed as a type I transmembrane glycoprotein that possesses a 546aa extracellular region (aa60-605) and a 159aa cytoplasmic domain (aa626-784). The extracellular region shows five consecutive cadherin domains. Over aa22-605, mouse CDH-15 shares 88% and 97% aa sequence identity with human and rat CDH-15, respectively.