MECHANISMS OF CHIEF CELL DEDIFFERENTIATION

主要细胞去分化的机制

基本信息

批准号：
10020395
负责人：
Jason C Mills
金额：
$ 44.14万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-09-30 至 2021-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10020395
关键词：
3-Dimensional Address Apoptosis Applications Grants Architecture Automobile Driving Autophagocytosis Award Back Bacteria Binding Cell Cycle Cell Cycle Stage Cell Differentiation process Cells Cellular Stress Cellular Structures Cessation of life ChIP-seq Chief Cell Chronic Chronic Disease Clustered Regularly Interspaced Short Palindromic Repeats Complex Data Development Disease Disease model Dysplasia Electron Microscopy Enzymes Epitopes Event Future Gene Expression Genes Genetic Genetic Transcription Goals Helicobacter pylori Human Hyperactive behavior Infection Inflammation Initiator tRNA Injury Knockout Mice Knowledge Lesion Malignant Neoplasms Messenger RNA Metaplasia Mitosis Modeling Molecular Mus Mutagenesis Natural regeneration Organ Organoids Output Pathway interactions Patients Pharmacology Phenotype Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Physiological Process Proteins Repression Research Resistance Ribosomes Risk Role S Phase Sampling Scaffolding Protein Secretory Vesicles Stomach Stress Techniques Testing Tissue Microarray Tissues Translating Translations activating transcription factor 3 adult stem cell biological adaptation to stress cancer risk cell dedifferentiation chronic infection disease phenotype experimental study gastric tumorigenesis genetic manipulation human disease human tissue in vivo malignant stomach neoplasm mouse model new therapeutic target overexpression paligenosis polyposis progenitor programs protein complex recruit repaired response scaffold spasmolytic polypeptide transcription factor transcriptome sequencing translation factor tumorigenesis

项目摘要

PROJECT SUMMARY We study how injury and inflammation induce mature cells like the digestive-enzyme-secreting zymogenic chief cell (ZC) to disassemble their complex cell architecture and re-enter the cell cycle. We previously showed that ZCs become proliferative via a sequence of molecular-cellular events conserved across many tissues and species in scenarios where mature cells are recruited back into the cell cycle in response to tissue damage. Thus, cells have an evolutionarily conserved program for this reprogramming, as they do for death (apoptosis) and division (mitosis). We call this program paligenosis and showed that mature cells: first degrade/recycle their differentiated cell components (Stage 1), then induce expression of progenitor-like genes (eg. Sox9 = Stage 2), and finally re-enter the cell cycle (Stage 3). Paligenotic ZCs convert to cells that can be seen histopathologically as the type of metaplasia that occurs in stomach during long-term infection with the bacterium Helicobacter pylori: pseudopyloric or Spasmolytic Polypeptide Expressing Metaplasia (SPEM). Metaplasia can either resolve as tissue is repaired or become chronic and increase risk for progression to dysplasia and cancer. We have shown that paligenosis is governed by dynamic changes in mTORC1, the cellular translation control protein complex. mTORC1 is elevated at baseline in ZCs to drive translation of digestive enzymes, it shuts off at Stage 1, and reactivates at Stage 3. Without mTORC1, paligenosis stops at Stage 2 with cells looking metaplastic, but unable to enter S-phase. Here, we explore the mechanisms that induce and promote paligenosis. We show preliminary data implicating the Integrated Stress Response (ISR) pathway as a central paligenosis hub with a particular role for the transcription factor Atf3, which is associated with the ISR, and another gene which we hypothesize is a target of ATF3: Ifrd1, a multifunctional scaffolding protein. We hypothesize that the stress of large-scale tissue damage and/or inflammation triggers ISR hyperactivity, which leads to greatly increased ATF3 and IFRD1, to help push cells back into the cell cycle. In the absence of Atf3 or Ifrd1, we show paligenosis is defective. Our Specific Aims will be: 1) to confirm and further characterize at which stages ISR is active and confirm and characterize the role for ATF3 using, in part Atf3−/− mice; 2) to identify additional genes involved in the ISR and paligenosis by confirming the role of IFRD1 with Ifrd1−/− mice, probe relative contributions of ATF3 and IFRD1 by characterizing double knockout mice, and finally to perform ChIP- and RNA- Seq during paligenosis ±ATF3; 3) to test known ATF3 and ISR genes and new targets developed in Aim 2 in a pipeline of more physiological disease models (eg chronic infection of mice with H pylori), human translational samples (Tissue Microarray and additional human samples of metaplasia and cancer with nearly a 1000 patients), and in a mouse model of tumorigenesis ±ATF3. Together, the experiments may help us understand fundamental mechanisms cells use in regeneration and tumorigenesis that apply not just to the stomach but potentially other organs as well.

项目摘要我们研究损伤和感染如何影响成熟的细胞，例如消化酶的分泌Zymogen opent 细胞（ZC）拆卸其复杂的细胞结构并重新进入细胞周期。我们以前表明 ZC通过在许多组织中保守的一系列分子 - 细胞事件来增殖在响应组织损伤的情况下，将成熟细胞招募到细胞周期的情况下。这是针对此重编程的进化配置的程序，就像死亡（凋亡）一样和分裂（有丝分裂）。我们称此程序占地病，并表明成熟的细胞：第一次降解/回收它们分化的细胞成分（第1阶段），然后影响祖细胞样基因的表达（例如Sox9 = 第2阶段），最后重新进入细胞周期（第3阶段）。 pal根ZC转换为可以看到的细胞在组织病理学上是长期感染期间陷阱中发生的化生的类型细菌幽门螺杆菌：表达化生的假性或痉挛性多肽（SPEM）。随着组织的修复或变为慢性，化生可以解决，并增加进展的风险发育不良和癌症。我们已经表明，丙泊症受MTORC1的动态变化控制细胞翻译控制蛋白复合物。 MTORC1在ZCS的基线时升高，以驱动翻译消化酶，它在第1阶段关闭，并在第3阶段重新激活。没有mtorc1，paligenisoise停在第2阶段，细胞看起来很塑性，但无法进入S期。在这里，我们探讨了影响和促进邻苯式病的机制。我们显示初步数据将综合应力反应（ISR）途径隐含为中央邻位型枢纽，具有特殊作用与ISR相关的转录因子ATF3，我们假设的另一个基因是一个 ATF3的靶标：IFRD1，一种多功能脚手架蛋白。我们假设大型组织的应力损坏和/或炎症触发ISR多动症，导致ATF3和IFRD1大大增加到帮助将细胞推回细胞周期。在没有ATF3或IFRD1的情况下，我们表明丙泊症是有缺陷的。我们的具体目的是：1）确认并进一步表征ISR的活动和确认的阶段以及表征使用ATF3的作用，部分是ATF3 - / - 小鼠； 2）确定ISR和ISR中涉及的其他基因通过证实IFRD1对IFRD1 - / - 小鼠的作用，探针相对贡献ATF3和IFRD1的作用通过表征双基因敲除小鼠，最后在paligenisois中执行芯片和RNA-seq±ATF3； 3）测试已知的ATF3和ISR基因以及在AIM 2中开发的新靶疾病模型（例如，幽门螺杆菌对小鼠的慢性感染），人翻译样品（组织微阵列以及其他几乎1000名患者的化生和癌症的其他人类样本），在小鼠模型中肿瘤发生±ATF3。共同进行实验可以帮助我们了解细胞使用的基本机制在再生和肿瘤发生中，不仅适用于摊位，而且还适用于其他可能的器官。