Combinatoial CREB/ATF dimers and cellular growth control

CREB/ATF二聚体组合和细胞生长控制

• 批准号: 6608067
• 负责人: Wayne P Wahls
• 金额: $ 24.37万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6608067
• 关键词: DNA binding protein; Schizosaccharomyces pombe; X ray crystallography; binding sites; biological signal transduction; cAMP response element binding protein; cell growth regulation; dimer; gel mobility shift assay; mass spectrometry; matrix assisted laser desorption ionization; mitogen activated protein kinase; polymerase chain reaction; protein protein interaction; stress proteins; transcription factor

APPLICANT'S DESCRIPTION: Proteins of the ATF/CREB/AP-1 family are components of signal transduction pathways that monitor intracellular and extracellular conditions and transmit those signals to downstream targets. Some family members (e.g., vFos and vJun) are oncogenic. ATF/CREB/AP-1 proteins share a conserved bZIP domain that mediates both protein dimerization and sequence-specific DNA binding activity. While the bZIP domains are highly homologous to one another, some combinations of bZIP proteins form dimers, while others do not. Furthermore, different bZIP dimers have the remarkable ability to discriminate between closely related DNA binding sites. This enables a limited set of bZIP monomers to form a repertoire of heterodimers, each of which presumably regulates the expression of a specific set of genes involved in a particular biological response. An understanding of which bZIP protein dimers can form, what DNA sites they occupy, and how such events are regulated will reveal fundamental aspects in the control of cellular homeostasis and/or differentiation. The fission yeast S. pombe provides an attractive model organism for such a study. We have shown that bZIP proteins of fission yeast form combinatorial dimers in vivo and in vitro. The various dimers are under control of a MAP kinase cascade and different dimers elicit distinct effector functions. Because S. pombe has a small genome (about 6,000 genes), and the sequencing project is nearly complete, one can identify and analyze the majority of cellular bZIP proteins. Since mutants lacking bZIP proteins and signal transduction proteins are generally viable, it is also possible to reveal both upstream regulatory and downstream effector functions. A comprehensive and systematic analysis of bZIP protein dimers of fission yeast is proposed. Aim 1, To elucidate the bZIP alphabet of S. pombe: determine pairwise combinatorial associations of bZIP dimers and identify DNA sites to which they bind with high affinity. Aim 2, To reveal molecular determinants of combinatorial dimer formation and DNA binding: compare high-resolution structures of bZIP dimers alone and complexed to their DNA sites. Aim 3, To further characterize regulatory mechanisms for stress responses mediated by the Mts1 bZIP protein: elucidate the role of the MAP kinase Spcl in controlling an autoinhibitory function of Mts1.

申请人的描述：ATF/CREB/AP-1家族的蛋白质是 信号转导途径，监测细胞内和细胞外 条件并将这些信号传输到下游目标。一些家庭 成员（例如VFO和VJUN）是致癌的。 ATF/CREB/AP-1蛋白共享 介导蛋白质二聚化和 序列特异性DNA结合活性。而BZIP域则高度 彼此同源，BZIP蛋白的某些组合形成二聚体， 而其他人则没有。此外，不同的BZIP二聚体具有显着的 能够区分密切相关的DNA结合位点的能力。这可以 有限的BZIP单体组形成异二聚体的曲目，每一个 大概调节了涉及的一组基因的表达 在特定的生物学反应中。对哪种BZIP蛋白的理解 二聚体可以形成，它们所占据的DNA位点以及如何调节此类事件 将揭示控制细胞稳态和/或控制的基本方面 分化。裂变酵母菌S. Pombe提供了一个有吸引力的模型 这项研究的生物体。我们已经证明了裂变酵母的BZIP蛋白 在体内和体外形成组合二聚体。各种二聚体不在 控制地图激酶级联反应和不同二聚体会引起独特的效应器 功能。因为S. pombe的基因组很小（大约6,000个基因），并且 测序项目几乎完成，可以识别和分析 大多数细胞BZIP蛋白。由于缺乏BZIP蛋白的突变体和 信号转导蛋白通常是可行的，也有可能 揭示上游调节和下游效应子功能。一个 BZIP蛋白质二聚体的全面和系统分析 提出了。目标1，以阐明S. pombe的BZIP字母：确定 BZIP二聚体的成对组合关联，并将DNA位点识别为 它们与高亲和力结合。目标2，以揭示分子决定因素 组合二聚体形成和DNA结合：比较高分辨率 单独使用BZIP二聚体的结构，并将其复合到其DNA位点。目标3，to 进一步的调节机制是由 MTS1 BZIP蛋白：阐明MAP激酶SPCL在控制A的作用 MTS1的自身抑制功能。