Transcriptional coactivators in hematopoiesis

描述：（由申请人提供）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 辅活化剂CREB结合蛋白（CBP）和高度相关的p300， 多结构域核磷蛋白共激活因子， 与许多核蛋白发生物理相互作用。在人类中，染色体 涉及CBP的易位与白血病相关，CBI 单倍体功能不全导致Rubinstein-Taybi综合征（RTS的特征在于 智力迟钝，颅面缺陷和宽大脚趾和拇指，以及 肿瘤的异常发病率，包括白血病）。CBP的关键作用 和p300已经在小鼠中得到证实，其中任一基因的敲除导致 在胚胎第9至11.5天死亡。CBP，而不是p300，无效杂合子也 表现出严重的造血问题，有明显的B细胞， 程度，T细胞缺乏，以及发展癌症的倾向， 造血起源，包括淋巴细胞白血病。然而，机械 影响体内转录并导致如此严重的缺陷 表型基本上是未知的。该提案侧重于四个不同的 CBP/p300中的TF结合结构域，进化上保守的半胱氨酸 富含组氨酸的结构域1（CH 1），因为它与两个关键因素相互作用， 正常造血细胞功能的Ets-1。和STAT 5。使用Ets-1和STAT 5 作为模型TF，建议采用CBP和p300条件无效等位基因ii 用于阐明CBP和p300依赖性的小鼠和小鼠细胞模型系统 在正常和恶性造血转录中起作用。目标1： 定义Ets-1和STAT 5与细胞相互作用的分子规则， CBP和p300的CH结构域，并将其与 具有反式激活功能。目的2是确定CBP的体内作用 和p300在B和T细胞中的表达。 本研究所获得的CBI和p300突变小鼠将是有价值的模型 研究这些辅激活因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.