Ubi independent mRNA regulated proteins.

Long-term exposure to a microgravity environment leads to structural and functional changes in hearts of astronauts. Although several studies have reported mechanisms of cardiac damage under microgravity conditions, comprehensive research on changes at the protein level in these hearts is still lacking. In this study, proteomic analysis of microgravity-exposed hearts identified 156 differentially expressed proteins, and ubiquitinomic analysis of these hearts identified 169 proteins with differential ubiquitination modifications. Integrated ubiquitinomic and proteomic analysis revealed that differential proteomic changes caused by transcription affect the immune response in microgravity-exposed hearts. Additionally, changes in ubiquitination modifications under microgravity conditions excessively activated certain kinases, such as hexokinase and phosphofructokinase, leading to cardiac metabolic disorders. These findings provide new insights into the mechanisms of cardiac damage under microgravity conditions.

长期暴露于微重力环境，可引发宇航员心脏出现结构与功能层面的改变。尽管已有多项研究报道了微重力条件下心脏损伤的相关机制，但针对该类心脏组织蛋白质水平变化的系统性研究仍较为匮乏。本研究通过对微重力暴露后的心脏组织进行蛋白质组学（proteomic）分析，共鉴定出156个差异表达蛋白质；同时开展泛素化蛋白质组学（ubiquitinomic）分析，鉴定得到169个存在差异泛素化修饰的蛋白质。整合泛素化蛋白质组与蛋白质组联合分析结果显示，转录调控介导的蛋白质组差异变化，会影响微重力暴露后心脏的免疫应答过程。此外，微重力环境下的泛素化修饰异常，会过度激活己糖激酶（hexokinase）、磷酸果糖激酶（phosphofructokinase）等部分激酶，进而引发心脏代谢紊乱。本研究结果为阐明微重力环境下心脏损伤的分子机制提供了全新的视角。