The W element is a positive regulator of HLA-DRA transcription in various DR+ cell types.
The W and P elements are cis-acting transcriptional regulators of the human class II MHC gene HLA-DRA necessary for maximal promoter activity in DR+ B cells. Proteins that bind specifically to W may mediate promoter activity from a DNA segment containing W and P (W/P). In this report, we demonstrate that a -143 to -123 bp region that lacks P is sufficient to mediate the W elements function and to bind the W proteins W-B1 and W-B2 in the Raji B-lymphoblastoid cell line. In contrast to previous reports, we find that W/P is not a B cell-specific element; rather that its promoter activity parallels active transcription of the endogenous DRA gene. In addition, we show that tissue-restricted regulation by W/P is not correlated with the ubiquitous (W-B1) and lymphoid-specific (W-B2) distribution of the W binding proteins. We suggest that mechanisms in addition to binding to W may account for W/P-dependent transcriptional activation in DR+ cells.
Cogswell
J P
JP
Department of Microbiology and Immunology, University of North Carolina, Chapel Hill 27599-7295.
Austin
J
J
Ting
J P
JP
D001402:B-Lymphocytes / Q000378:metabolism*; D001483:Base Sequence; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics; D006684:HLA-DR Antigens / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid / Q000502:physiology*; D014158:Transcription, Genetic / Q000235:genetics
D004268:DNA-Binding Proteins; D006684:HLA-DR Antigens