The pathophysiological relevance of the histone variant H2A.J in radiation-induced, premature senescence

组蛋白变体 H2A.J 在辐射诱导的过早衰老中的病理生理学相关性

• 批准号: 394229105
• 负责人: Professorin Dr. Claudia Rübe
• 金额: --
• 依托单位: Klinik für Strahlentherapie und Radioonkologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/394229105?language=en
• 关键词: pathophysiological; relevance; histone; variant; H2A.J

The long term side effects following radiotherapy can be traced back to the accumulation of dysfunctional senescent cells combined with the reduced proliferative potential of tissue-specific stem cells; to date the pathomechanisms however remain unclear. In our preliminary studies, we have characterized the novel histone variant H2A.J, whose integration into chromatin increases following ionizing radiation and additionally is associated with cellular senescence.The aim of this research project is to investigate the importance of the histone variant H2A.J in relation to radiation-induced, premature senescence both in-vitro and in-vivo. The molecular biological relationship between radiation-induced DNA damage, local chromatin modifications and subsequent global reorganization of the chromatin architecture is to be investigated using comparative studies between H2A.J+/+ and H2A.J-/- fibroblasts through the means of light- and electron microscopy. Additionally, the alterations in chromatin organization and nuclear integrity shall be structurally and functionally characterized using multi-parametric flow cytometry. The application of high-resolution, precise 3D reconstruction of the entire cell nucleus shall be used to uncover the connections between the chromatin integration of H2A.J following irradiation and the functional reorganization of chromatin.Furthermore, the functionality of H2A.J is to be investigated in the complex tissue configuration of the skin, during and after irradiation. Located in the murine epidermis is the hair follicle and its bulge region which presents an ideal model for the analysis of the differentiation processes of epidermal stem cells. To examine the effect on tissue homeostasis, the radiation-induced DNA damage in different stem cell populations shall be correlated with the chromatin integration of H2A.J and collated with proliferation, differentiation, apoptosis and senescence respectively. Analysis of the specific function of H2A.J in the epidermis shall be inspected in transgenic H2A.J-/- mice. In specific, how the missing H2A.J expression influences premature senescence or, as the case may be, the untimely differentiation of epidermal stem cells, following irradiation. The use of BrdU labeling will capture the division rate, as well as, the self-renewal of the stem cell population and, combined with H2A.J detection, will be collated with premature differentiation. As increased migration of stem cells from their niche leads to a reduced regeneration capacity of the hair follicle in the long term, the functional endpoint of hair growth and coloring shall be analyzed.Overall, the pathophysiological relevance of the histone variant H2A.J in radiation-induced, premature senescence and the untimely differentiation of epidermal stem cells respectively, is to be investigated to uncover possible starting points for the development of a corrective pharmacological therapy.

放疗后的长期副作用可以追溯到功能失调的衰老细胞的积累，并结合组织特异性干细胞的增殖潜力降低。迄今为止，病理机制尚不清楚。在我们的初步研究中，我们表征了新型的组蛋白变体H2A.J，其在电离辐射后的整合和染色质增加与细胞衰老有关。该研究项目的目的是研究组蛋白变体H2A.J在辐射诱导的，早产，侵袭性和侵袭性中的重要性。辐射诱导的DNA损伤，局部染色质修饰和随后的染色质结构的全局重组之间的分子生物学关系，可以通过H2A.J+/+和H2A.J-/ - 成纤维细胞之间的比较研究通过光和电子显微镜拷贝进行研究。此外，使用多参数流式细胞仪在结构和功能上的染色质组织和核完整性的改变应在结构和功能上进行表征。整个细胞核的高分辨率，精确的3D重建的应用应用于揭示H2A.J辐照后H2A.J的染色质整合与染色质的功能重组之间的连接。FURTHERMORE.FURTHERMORE，H2A.J的功能，H2A.J的功能应在复杂的组织结构和后期的irradiation in riradiation in Complip Handioration中进行研究。位于鼠表皮中的是毛囊及其凸起区域，它为分析表皮干细胞分化过程提供了理想的模型。为了检查对组织稳态的影响，辐射诱导的不同干细胞群体中的DNA损伤应与H2A.J的染色质整合相关，并分别与增殖，分化，凋亡和衰老分别整理。对表皮中H2A.J的特定功能的分析应在转基因H2A.J - / - 小鼠中检查。具体而言，丢失的H2A.J表达如何影响过早衰老，或者在情况下可能会在照射后不合时宜地分化表皮干细胞。 BRDU标签的使用将捕获干细胞种群的自我更新，并与H2A.J检测结合使用，将与过早的分化进行整理。长期以来，随着干细胞从其利基的迁移增加导致毛囊的再生能力降低，应分析毛发生长和着色的功能终点。随后，组蛋白变异H2A.J的病理生理相关性H2A.J在辐射中诱导的递增的启动和散热细胞的开发是相应的，这是在辐射中的相分化的差异，是相应地构成差异性的。矫正药理学疗法。