Mouse IgD half molecules with shortened IgD heavy chain result from alterations within C delta locus.
An unusually small (51 KD) IgD myeloma protein was isolated from secretions of TEPC 1017 generation (gen) 24. The delta-chain mRNA and the delta-chain gene in this tumor were compared with those of TEPC 1017 of earlier generations. The gen 24 protein contained one normal-sized kappa-type light chain (21 KD) and one unusually short delta-heavy chain (30 KD). The delta-heavy chain was 15 KD shorter than that of TEPC 1017 of earlier generations, owing to a delta-mRNA (1.15 kb) which was 600 bp shorter than that of TEPC 1017 of earlier generations. TEPC 1017 is a tetraploid tumor, and the gen 24 appears to contain at least two different deletions on different chromosomes. The short mRNA was produced from one of these altered delta-chain genes which had a productive VDJ rearrangement but which had lost the C delta 3 domain and perhaps the C delta H domain as well. Despite these genetic insults, RNA splicing produced delta-mRNA with secreted termini and mRNA with membrane-binding termini. It is suggested that the mouse C delta gene has an unusual predilection for deletions because it normally lacks any vestige of C delta 2 and, during i.p. passage, it suffered further deletions or alterations.
D000818:Animals; D002872:Chromosome Deletion; D007127:Immunoglobulin Constant Regions / Q000235:genetics*; D007072:Immunoglobulin D / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007138:Immunoglobulin delta-Chains / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000302:isolation & purification; D007136:Immunoglobulins / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D009194:Myeloma Proteins / Q000032:analysis; D010954:Plasmacytoma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis
D007127:Immunoglobulin Constant Regions; D007072:Immunoglobulin D; D007143:Immunoglobulin Heavy Chains; D007138:Immunoglobulin delta-Chains; D007145:Immunoglobulin kappa-Chains; D007136:Immunoglobulins; D009194:Myeloma Proteins; D012333:RNA, Messenger