Transcriptional coactivators in hematopoiesis

描述：(申请人提供)该提案的长期目标是 了解控制血细胞发育的转录因子(TF) 和功能通过与转录因子相互作用来调节基因表达 助活剂。CREB结合蛋白(CBP)和高度相关的p300，是很大的 多结构域核磷蛋白共激活子，功能和 在物理上与许多核蛋白相互作用。在人类中，染色体 涉及CBP的易位与白血病和CBI相关 单核细胞不足导致Rubinstein-Taybi综合征(RTS)的特征是 智力低下，头面部缺陷和宽大的拇指和拇指，以及 肿瘤的异常发生率，包括白血病)。CBP的关键作用 而p300已经在小鼠身上被证实，其中任何一个基因的敲除都会导致 胚胎9至11.5天死亡。CBP，BU不是p300，也是零杂合子 在标记的B细胞中表现出严重的造血问题，对一些人来说 程度、T细胞缺陷和发生癌症的易感性 血液病起源，包括淋巴细胞白血病。然而，机械论 缺陷(S)，影响体内转录并导致如此严重的 表型在很大程度上是未知的。该提案的重点是四个不同的 进化保守的半胱氨酸CBP/p300中的Tf结合结构域 富含组氨酸的结构域1(CH1)，因为它与两个关键因素相互作用 对于正常的造血细胞功能，ETS-1。和STAT5。使用ETS-1和STAT5 作为模型因子，建议使用CBP和p300条件零等位基因II 小鼠和小鼠细胞模型系统阐明CBP和p300依赖 在正常和恶性造血转录中的作用。目标1是 定义控制ETS-1和STAT5与Ets-1和STAT5相互作用的分子规则 CBP和p300的CH结构域的定点突变及其相互关系 具有激活功能。目的2是确定CBP在体内的作用 通过使用CBP和p300条件基因敲除小鼠，在B细胞和T细胞中表达p300。 这项研究中产生的cbi和p300突变小鼠将是有价值的模型。 研究这些辅活化子在其他生理过程中的作用 与人类健康有关，包括记忆、生殖、生长、衰老和 新陈代谢。

DESCRIPTION: (provided by applicant) The proposal's long-term goal is to understand how transcription factors (TFs) that control blood cell development and function regulate gene expression by interacting with transcriptional coactivators. CREB-binding protein (CBP) and the highly related p300, are large multi-domain nuclear phosphoprotein coactivators that functionally and physically interact with many nuclear proteins. In humans, chromosomal translocations involving CBP are associated with leukemia, and CBI haplo-insufficiency leads to Rubinstein-Taybi Syndrome (RTS is characterized by mental retardation, craniofacial defects and broad big toes and thumbs, and an abnormal incidence of neoplasms, including leukemia). A crucial role for CBP and p300 has been demonstrated in mice where knockouts of either gene result in death at embryonic days 9 to 11.5. CBP, bu not p300, null heterozygotes also exhibit severe problems in hematopoiesis with marked B-cell and, to some degree, T-cell deficiencies, and a predisposition for developing cancers of hematopoietic origin, including lymphocytic leukemia. However the mechanistic defect(s) that affects transcription in vivo and leads to such severe phenotypes is largely unknown. The proposal focuses on one of the four distinct TF-binding domains in CBP/p300, the evolutionarily conserved Cysteine Histidine-rich domain 1 (CH 1), because it interacts with two factors critical for normal hematopoietic cell function, Ets-1. and STAT5. Using Ets-1 and STAT5 as model TFs, it is proposed to employ CBP and p300 conditional null alleles ii mouse and mouse-cell model systems to elucidate CBP- and p300-dependent functions in normal and malignant hematopoietic transcription. Aim 1 is to define the molecular rules governing the Ets-1 and STAT5 interaction with the CH domain of CBP and p300 by site-directed mutagenesis, and to correlate this with transactivation function. Aim 2 is to determine the in vivo role of CBP and p300 in B- and T-cells by using CBP- and p300-conditional knockout mice. The CBI and p300 mutant mice generated in this study will be valuable models for examining the roles of these coactivators in other physiological processes relevant to human health, including memory, reproduction, growth, aging, and metabolism.