Formation of secreted and membrane laM “g3UT r“m73U R■了 圃 L Y DJ C Mg 3'UT m 3'UT ■ LV D J CHI Cp2 CH3 Cu4 Translated into Secreted IgM man- H chains have five chains as previously described.Each isotype and homology region genes are encoded by genes separated by intervening sequence or introns.Thus. composed ofn in contrast toL chain constant domain (CL) genes. erestingly,all of the different classes and subclasses of Ifs us the same s of V region genes.Thus if the class or subclass is change,only the C region is switched. H chain class switching. X■M H DH JH HMH Trans cription Second DNA Reagttangement S.S ■ 皿 ■外 ￥DJC LV D J CE Y D J Cu Transc ption Y D J CY2b Class switchingH chains have five chains as previously described. Each isotype and homology region is encoded by genes separated by intervening sequence or introns. Thus, CH genes are composed of multiple exons in contrast to L chain constant domain (CL) genes. Interestingly, all of the different classes and subclasses of Ifs us the same set of V region genes. Thus if the class or subclass is change, only the C region is switched