title: A variable region subclass of heavy chains common to immunoglobulins G, A, and M and characterized by an unblocked amino-terminal residue.
abstract: Heavy chains of IgG, IgA, and IgM classes of human immunoglobulins were compared by N-terminal residue determination and partial amino acid sequence analysis. A third subclass of the variable region of heavy chains was observed; an unblocked glutamic acid as the N-terminal residue is characteristic of this subclass. Our results indicated that the heavy chain variable region subclasses are not class specific, and that a given heavy chain variable region may be found in association with constant regions for mu-chains, alpha-chains, or gamma-chains of various subclasses.
mesh_terms: D000595:Amino Acid Sequence; D000917:Antibody Formation; D000921:Antibody-Producing Cells; D002855:Chromatography, Thin Layer; D002999:Clone Cells / Q000276:immunology; D005796:Genes; D006801:Humans; D006827:Hydantoins; D007074:Immunoglobulin G / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis*; D007136:Immunoglobulins / Q000032:analysis / Q000145:classification; D009101:Multiple Myeloma / Q000097:blood; D010455:Peptides / Q000032:analysis* / Q000145:classification; D010950:Plasma Cells / Q000276:immunology; D008258:Waldenstrom Macroglobulinemia / Q000097:blood
chemical_list: D006827:Hydantoins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins; D010455:Peptides