Cogswell J P, Austin J, Ting J P
Department of Microbiology and Immunology, University of North Carolina, Chapel Hill 27599-7295.
J Immunol. 1991 Feb 15;146(4):1361-7.
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.
W和P元件是人类II类MHC基因HLA - DRA的顺式作用转录调节因子，对于DR + B细胞中的最大启动子活性是必需的。特异性结合W的蛋白质可能介导来自包含W和P（W/P）的DNA片段的启动子活性。在本报告中，我们证明了缺乏P的-143至-123 bp区域足以介导W元件的功能，并在Raji B淋巴母细胞系中结合W蛋白W - B1和W - B2。与先前的报告相反，我们发现W/P不是B细胞特异性元件；相反，其启动子活性与内源性DRA基因的活跃转录平行。此外，我们表明W/P的组织限制性调节与W结合蛋白的普遍存在（W - B1）和淋巴细胞特异性（W - B2）分布无关。我们认为，除了与W结合之外的机制可能解释了DR +细胞中W/P依赖性转录激活。
