Regulation of a transfected human class II major histocompatibility complex gene in human fibroblasts.
To investigate the cis-acting DNA elements that are involved in regulation of class II major histocompatibility complex genes, including gamma-interferon (gamma-IFN) induction, 5' flanking DNA deletions of a DQ beta "minigene" were analyzed in stable transfected cell lines. At least four elements 5' to the gene were found to be involved in DQ beta regulation. Deletion of sequences from -2500 to -159 base pairs (bp) resulted in increased transcription, suggesting that negative regulatory elements resided in the deleted region. These clones were all capable of responding to gamma-IFN. Further deletion of sequences from -159 to -128 bp resulted in constitutive high level transcription and the inability of these constructions to respond to gamma-IFN. A deletion to -107 bp resulted in a decrease in the basal level of expression that was restored by removal of the 5' DNA sequence to -82 bp, suggesting the presence of a second negative element. Finally, deletion to -64 bp caused a marked decrease in expression, suggesting the loss of an element necessary for high levels of transcription. The gamma-IFN control and the transcription control elements contain the conserved upstream sequences found in all class II genes, suggesting a role for these sequences.
D005347:Fibroblasts; D005786:Gene Expression Regulation; D005809:Genes, Regulator; D005818:Genetic Engineering; D006681:HLA-D Antigens / Q000235:genetics*; D006683:HLA-DQ Antigens / Q000235:genetics*; D006801:Humans; D007371:Interferon-gamma / Q000502:physiology*; D008285:Major Histocompatibility Complex; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014162:Transfection
D006681:HLA-D Antigens; D006683:HLA-DQ Antigens; D012333:RNA, Messenger; D007371:Interferon-gamma