CLONING RHESUS CD94 NKG2 A & NKG2 C NK CELL RECEPTOR CDNAS FROM PREGNANT DECIDU

目的探讨Sp家族成员结合位点的作用 在生长激素变异基因转录中的作用。 结果以确定 普遍存在Sp家族转录因子在GH-V中可能发挥的作用 转录，我们进行了共转染实验，其中 将不同量的Sp1、Sp3或这两种因子引入细胞中 以确定这些因子是否可以直接激活转录， 发起人。 Sp1处理诱导了基础胰岛素和胰岛素水平的适度增加。 和cAMP刺激的转录; Sp3对 基础或cAMP诱导的活性，并且可能在 更高的水平。 两者之间无协同活性 因素 这些结果表明，Sp./ 3、不起任何作用，或 不限于GH-V转录。 这个发起人的一个关键事实是 是转录所需的Sp位点和邻近元件。 我们推断，既然转录的基本要素 激活位于-140/-111和-65/-42区域内， 在这两个因素之间存在着合作活动， 地区 我们希望确定是否存在严格的 这两个要素的要求，或者是否任何一个要素 可以替代另一个串联，从而提供一个可能的 酵母单杂交筛选方法的增强子。 构建体 用-140/-105或-75/-35多联体制备（多个正向和 反向排列）。 瞬时转染的结果 实验表明，存在协同效应， 添加1个或2个额外的-140/-105元件拷贝，以及 有一个要求，副本必须在同一个 取向（即，头对头的安排不起作用 而头对尾排列显示出与对照相比的协同活性。 单一副本）。 因此，结果表明：1）多个拷贝的 每个元素都是激活所必需的，2）特定的 空间组织是合作激活的必要条件; 分离的元件在异源启动子的作用下是有功能的。 关键 胎盘，基因转录，胎盘生长激素， 转录因子基金NIH R 01 HD26458

OBJECTIVE To determine the roles of Sp family member binding sites in growth hormone variant gene transcription. RESULTS To determine the role ubiquitous Sp famila transcription factors may play in GH-V transcription, we conducted co-transfection experiments in which varied amounts of Sp1, Sp3 or both factors were introduced into cells to determine if the factors can directly activate transcription from the promoter. Sp1 treatment induced a modest increase in both basal and cAMP-stimulated transcription; Sp3 had no stimulatory effect on either basal or cAMP-induced activity, and may have been inhibitory at higher levels. There was no synergistic activity between the two factors. These results suggest that Sp./3 either plays no role in, or are not limiting for GH-V transcription. A key fact of this promoter is that Sp sites and adjacent elements are required for transcription. We reasoned that since essential elements for transcriptional activation were located within both the -140/-111 and -65/-42 regions, that there was cooperative activity between factors bound in these two regions. We wished to determine whether there was a strict requirement for these two elements, or whether either of the elements could substitute for the other in tandem and thus provide a possible enhancer for yeast 1-hybrid screening approaches. Constructs were prepared with -140/-105 or -75/-35 concatamers (multiple forward and reverse arrangements). The results of transient transfection experiments demonstrated that there was a synergistic effect of addition of 1 or two additional copies of the -140/-105 element, and that there was a requirement for the copies to be in the same orientation (i.e., a head to head arrangement was not functional whereas a head to tail arrangement showed synergistic activity over a single copy). The results thus demonstrate that 1) multiple copies of ea ch of the elements are necessary for activation, 2) specific spatial organization is necessary for cooperative activation, and 3) isolated elements are functional with a heterologous promoter. KEY WORDS placenta, gene transcription, placental growth hormone, transcription factors FUNDING NIH R01 HD26458