title: Multiple mechanisms regulate the expression of murine immune response genes.
abstract: The immune response antigens (la antigens) are heterodimeric cell-surface glycoproteins that regulate lymphocyte and macrophage interactions leading to the production of antibody against foreign antigens. The class II genes in the I region of the murine major histocompatibility complex encode the alpha and beta chains of the two known la antigens, I-A and I-E. Molecular cloning of the I region led to the discovery of three DNA regions, A beta 2, psi A beta 3, and E beta 2, which share some nucleotide homology with the classical class II beta genes. In this report we present evidence that A beta 2 is transcribed in spleen and in a cultured B cell hybridoma. A beta 2 mRNA is also found on membrane-bound polysomes, suggesting that it is translated. In contrast to the classical I region genes, A beta 2 transcripts are not induced in macrophage cells by gamma-interferon (gamma-IFN). This difference in sensitivity to gamma-IFN suggests that B cells and macrophages regulate the expression of the class II genes by distinct mechanisms.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D001483:Base Sequence; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II; D006825:Hybridomas; D007371:Interferon-gamma / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D013154:Spleen / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D000949:Histocompatibility Antigens Class II; D012333:RNA, Messenger; D007371:Interferon-gamma