Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572006, China.
State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing 102206, China.
Science. 2024 Oct 25;386(6720):eadl0799. doi: 10.1126/science.adl0799.
Tardigrades are captivating organisms known for their resilience in extreme environments, including ultra-high-dose radiation, but the underlying mechanisms of this resilience remain largely unknown. Using genome, transcriptome, and proteome analysis of , we explored the molecular basis contributing to radiotolerance in this organism. A putatively horizontally transferred gene, DOPA dioxygenase 1 (), responds to radiation and confers radiotolerance by synthesizing betalains-a type of plant pigment with free radical-scavenging properties. A tardigrade-specific radiation-induced disordered protein, TRID1, facilitates DNA damage repair through a mechanism involving phase separation. Two mitochondrial respiratory chain complex assembly proteins, BCS1 and NDUFB8, accumulate to accelerate nicotinamide adenine dinucleotide (NAD) regeneration for poly(adenosine diphosphate-ribosyl)ation (PARylation) and subsequent poly(adenosine diphosphate-ribose) polymerase 1 (PARP1)-mediated DNA damage repair. These three observations expand our understanding of mechanisms of tardigrade radiotolerance.
水熊虫是一种引人入胜的生物，以其在极端环境中的弹性而闻名，包括超高剂量的辐射，但这种弹性的潜在机制在很大程度上仍然未知。使用基因组、转录组和蛋白质组分析，我们探讨了促成这种生物耐辐射的分子基础。一种推测的水平转移基因，DOPA 双加氧酶 1 ()，对辐射做出反应，并通过合成甜菜碱来赋予耐辐射性-一种具有自由基清除特性的植物色素。一种水熊虫特异性的辐射诱导无序蛋白 TRID1 通过涉及相分离的机制促进 DNA 损伤修复。两种线粒体呼吸链复合物组装蛋白 BCS1 和 NDUFB8 积累以加速烟酰胺腺嘌呤二核苷酸 (NAD) 的再生，用于聚（腺苷二磷酸核糖基）化 (PARylation) 和随后的多聚（腺苷二磷酸核糖）聚合酶 1 (PARP1)介导的 DNA 损伤修复。这三个观察结果扩展了我们对水熊虫耐辐射机制的理解。
