CIITA and MHC II Transcription

CIITA 和 MHC II 转录

基本信息

批准号：
7155522
负责人：
Boris Matija PETERLIN
金额：
$ 28.73万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-07-01 至 2007-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7155522
关键词：
Acetylation Alanine Antigen Presentation Pathway Antigen-Presenting Cells Applications Grants B-Lymphocytes Bare Lymphocyte Syndromes Binding Biochemical Blinded CD4 Positive T Lymphocytes Cells Chromosomes, Human, Pair 6 Code Complex DNA Binding DNA-Binding Proteins Development Disease Education Genes Genetic Transcription Glutamates Grant Health Helper-Inducer T-Lymphocyte Histocompatibility Antigens Class II Human Immune response Immunoglobulin Class Switching Importins In Vitro Knock-in Mouse Knowledge MHC class II transactivator protein Maps Modification Mus Mutate Mutation Nuclear Export Nuclear Extract Nuclear Localization Signal Patients Phosphorylation Phosphorylation Site Phosphotransferases Physiology Play Post-Translational Protein Processing Process Protein Overexpression Proteins RFX regulatory factor RNA Interference Rate Regulation Role SLC26A3 gene Signal Transduction Site Stimulus Structure Tissues Transgenic Mice Ubiquitin Upper arm human CREB1 protein in vivo invariant chain mutant nuclear factor Y nucleocytoplasmic transport programs promoter tool transcription factor ubiquitin ligase

项目摘要

Transcription of major histocompatibility complex class II (MHCII) genes and thus antigen processing and presentation (APP) to CD4+ T helper cells and their education of MHCII-positive B cells for immunoglobulin class switching and hypermutation is carefully regulated in development and in tissues. Four separate transcription factors are dedicated solely to the transcription of structural MHCII genes, DMA/DMB and the invariant chain (Ii). Of these, the class II transactivator, CIITA plays a key role in turning these genes on and off following the administration of IFN3,. Recently, we discovered that in addition to IFN'y, antigen presenting cells (APC) require another signal that phosphorylates CIITA. Phosphorylation of CIITA leads to its oligomerization, accumulation and increased activity on MHCII promoters. CIITA is also not a DNA-binding protein but is somehow attracted to the MHCII enhanceosome, which assembles on conserved upstream sequences in these promoters. This grant will investigate the precise signals that are required for the full activity of CIITA, what posttranslational modifications occur and how they create super-CIITA complexes that trigger the full APP. First, nucleocytoplasmic shuttling of CIITA will be investigated in great detail. Precise NES and NLS will be mapped and confirmed functionally. Next, phosphorylation, acetylation and ubiquitylation of CIITA will be investigated in great detail. These sites will be mutated appropriately to resemble constitutively phosphorylated and acetylated forms of CIITA. Additionally, they will be changed so that they cannot be modified posttranslationally. Ubiquitin will be fused directly to CIITA. Forced oligomers of CIITA will also be made. All these modified CIITA proteins will be examined for binding the MHCII enhanceosome in vitro and for function in vivo. Moreover, kinases, HATs, HDACs, ubiquitin ligases that participate in these processes will be revealed. Finally, a super-CIITA protein will be created that does not require this second stimulus for full activity. This mutant CIITA protein/s will then program any cell for APP. It will be introduced into cells and into the murine germline, in place of the endogenous CIITA gene (knock-in) and with P 1 or P4 promoters of CIITA for expression in hematopoetic and nonhematopoetic cells, respectively, for induction of full APP following the administration of IFN'y. Collectively, these studies will reveal the normal physiology of CIITA, why it oligomerizes and shuttles, and create new tools to manipulate the immune response in health and disease.

主要组织相容性复合体 II 类 (MHCII) 基因的转录以及抗原加工和向 CD4+ T 辅助细胞呈递 (APP) 及其对 MHCII 阳性 B 细胞的教育免疫球蛋白类别转换和超突变在发育和组织中受到仔细调节。四个独立的转录因子专门用于结构 MHCII 基因的转录， DMA/DMB 和不变链 (Ii)。其中，II 类反式激活因子 CIITA 在施用 IFN3 后打开和关闭这些基因。最近，我们发现在除了 IFN'y 之外，抗原呈递细胞 (APC) 还需要另一种磷酸化 CIITA 的信号。 CIITA 磷酸化导致其寡聚化、积累并增加对 MHCII 的活性发起人。 CIITA 也不是 DNA 结合蛋白，但以某种方式被 MHCII 增强体吸引，它在这些启动子中的保守上游序列上组装。这笔赠款将调查准确的 CIITA 完整活动所需的信号、发生哪些翻译后修饰以及如何发生他们创建了触发完整 APP 的超级 CIITA 复合体。一、CIITA的核质穿梭将进行非常详细的调查。精确的 NES 和 NLS 将在功能上进行映射和确认。下一个， CIITA 的磷酸化、乙酰化和泛素化将得到详细研究。这些网站将适当突变以类似于 CIITA 的组成型磷酸化和乙酰化形式。此外，它们将被更改，以便它们不能在翻译后被修改。泛素将是直接与 CIITA 融合。 CIITA的强制低聚物也将被制造。所有这些修饰的 CIITA 蛋白将检查其体外结合 MHCII 增强体和体内功能。此外，激酶，参与这些过程的 HAT、HDAC、泛素连接酶将被揭示。最后来个超级CIITA 将产生不需要第二次刺激即可发挥全部活性的蛋白质。这个变异CIITA 然后蛋白质将对任何细胞进行 APP 编程。它将被引入细胞和小鼠种系中，内源 CIITA 基因（敲入）的位置和 CIITA 的 P 1 或 P4 启动子用于在造血细胞和非造血细胞，分别用于诱导完整的 APP IFN'y的施用。总的来说，这些研究将揭示 CIITA 的正常生理机能及其原因寡聚和穿梭，并创造新的工具来操纵健康和疾病中的免疫反应。