title: A transgenic immunoglobulin mu gene prevents rearrangement of endogenous genes.
abstract: Transgenic mice containing a microinjected rearranged immunoglobulin (Ig) mu heavy chain gene were examined for the effects on DNA rearrangement of the endogenous Ig genes. Abelson murine leukemia virus (A-MuLV) cell lines were isolated from pre-B cells of transgenic mice and of normal littermates. Microinjected mu gene RNA and a mu heavy chain protein were synthesized in every transgenic A-MuLV cell line. Only 10% of normal mouse A-MuLV transformants synthesized mu protein. A germ-line JH allele was observed in 40% of the transgenic lines, demonstrating that the block to endogenous Ig DNA rearrangement occurred at the first step of heavy chain DNA joining. All alleles were rearranged in normal mouse A-MuLV lines. Germline JH alleles were also detected in 10% of the transgenic hybridomas derived from proliferating B cells. Our results support a model of active prevention of rearrangement by the product of successfully rearranged mu genes.
mesh_terms: D000011:Abelson murine leukemia virus; D000483:Alleles; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation; D002460:Cell Line; D002472:Cell Transformation, Viral; D007128:Immunoglobulin Fragments / Q000235:genetics*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007144:Immunoglobulin J-Chains / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000235:genetics; D007148:Immunoglobulin mu-Chains / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008845:Microinjections; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D007128:Immunoglobulin Fragments; D007143:Immunoglobulin Heavy Chains; D007144:Immunoglobulin J-Chains; D007147:Immunoglobulin Light Chains; D007148:Immunoglobulin mu-Chains; D012333:RNA, Messenger