Molecular and physical mechanisms that underpin the αβ versus γδ T cell fate decision

支持 αβ 与 γδ T 细胞命运决定的分子和物理机制

• 批准号: 10226999
• 负责人: CORNELIS MURRE
• 金额: $ 15.23万
• 依托单位: RESEARCH INST OF FOX CHASE CAN CTR
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10226999
• 关键词: Adopted; Adoption; B-Lymphocytes; Binding Sites; Cell Lineage; Chromatin; Collaborations; Communication; DNA; Data; E protein; Elements; Enhancers; Four-dimensional; Genes; Genetic Transcription; Genomics; Grant; Kinetics; Link; Lymphoid Cell; Molecular; Motion; Movement; Names; Nuclear; Nuclear Lamina; Pathway interactions; Positioning Attribute; Process; Promoter Regions; Proteins; RUNX1 gene; Signal Transduction; Site; Specific qualifier value; T-Cell Development; T-Lymphocyte; TCF3 gene; Time; Transcript; Untranslated RNA; V(D)J Recombination; cohesin; experimental study; insight; morphogens; notch protein; novel strategies; progenitor; programs; promoter; stem cells; thymocyte; γδ T cells

PROJECT SUMMARY/ABSTRACT It is now well established that the onset of T cell development is initiated by the induction of Notch expression. During the previous grant cycle, we found that this critical step is controlled by the combined activities of E2A and HEB. Once Notch1 expression is activated, Notch signaling acts in concert with RUNX1, TCF1, E2A and GATA-3 to activate Bcl11b expression. Bcl11b next acts in concert with E2A to activate a T-lineage specific gene program. We (with Project 1) also demonstrated that E2A activates the expression of a non-coding transcript, named ThymoD, to reposition the Bcl11b enhancer from the nuclear lamina to the nuclear interior. These studies linked E-protein occupancy, non-coding transcription and Bcl11b expression into a common pathway that orchestrates the αβ versus γδ T cell fate decision. We now aim to describe, in physical and kinetic terms, Bcl11b locus movement relative to the onset of T cell development. To track genomic interactions in live lymphoid cells, we have developed a novel strategy. Specifically, we tracked the motion of DNA elements to visualize VDJ recombination in live B cells using tandem arrays of WT-TET and MUT-TET repressor binding sites. We propose to use the same strategy to describe in live T cells the trajectories of Bcl11b enhancer- promoter communication. Specifically, we will examine how Bcl11b enhancer-promoter communication is suppressed when sequestered at the nuclear lamina prior to commitment to the T cell lineage and after these loci return to the lamina upon adoption of the γδ T cell fate (with Projects 1 and 3). We will also examine how E-proteins and Notch signaling modulate Bcl11b enhancer-promoter communication to establish and maintain αβ T cell identity (with Projects 2 and 3) and how E-proteins, Notch signaling, non-coding transcription and nuclear repositioning are linked in four-dimensional space to orchestrate αβ T cell fate. Collectively these studies proposed here would be a first step towards describing the αβ versus γδ T cell fate choice in four- dimensional space and would not be possible outside of this integrated programmatic effort.

项目摘要/摘要 现已证实，T细胞发育的开始是由Notch的诱导表达启动的。 在之前的资助周期中，我们发现这一关键步骤由E2A的组合活动控制 和希伯来。一旦Notch1表达被激活，Notch信号就与RUNX1、TCF1、E2a和RUNX1协同作用 GATA-3激活Bcl11b的表达。Bcl11b接下来与E2a协同作用，激活T细胞系特异性 基因程序。我们(与项目1)还证明了E2A激活了非编码基因的表达 转录，命名为ThymoD，将Bcl11b增强子从核层重新定位到核内部。 这些研究将E蛋白占位、非编码转录和Bcl11b表达联系到一个共同的 协调αβ与γδT细胞命运决定的途径。我们现在的目标是在物理和动力学上描述 就术语而言，Bcl11b基因座的移动与T细胞发育的开始有关。在LIVE中跟踪基因组相互作用 淋巴样细胞，我们开发了一种新的策略。具体地说，我们追踪了DNA元素的运动 利用串联的WT-Tet和MUT-Tet阻遏物结合阵列显示VDJ在活B细胞中的重组 网站。我们建议使用相同的策略来描述活T细胞中Bcl11b增强子的轨迹- 推动者沟通。具体地说，我们将研究Bcl11b增强子-启动子之间的通信是如何 在承诺T细胞谱系之前和之后，当隔离在核层时被抑制 在通过γδT细胞命运(项目1和3)后，基因座返回到椎板。我们还将研究如何 E蛋白和Notch信号调节Bcl11b增强子-启动子通信建立和维持 αβT细胞特性(项目2和3)以及E蛋白、Notch信号、非编码转录和 核重新定位在四维空间中联系在一起，协调αβT细胞的命运。总的来说，这些 这里提出的研究将是描述四年内αβ与γδT细胞命运选择的第一步- 如果没有这一综合方案的努力，就不可能有更多的空间空间。