Table5_Variations in DNA methylation and the role of regulatory factors in rice (Oryza sativa) response to lunar orbit stressors.xlsx

Deep space flight imposes higher levels of damage on biological organisms; however, its specific effects on rice remain unclear. To investigate the variations in DNA methylation under deep space flight conditions, this study examined rice seeds carried by Chang’e-5. After 23 days of lunar orbital flight, the samples were planted in an artificial climate chamber and subjected to transcriptome and DNA methylation sequencing during the tillering and heading stages. The methylation patterns in the rice genome exhibited variability in response to lunar orbital stressors. DNA methylation alters the expression and interaction patterns of functional genes, involving biological processes such as metabolism and defense. Furthermore, we employed single-sample analysis methods to assess the gene expression and interaction patterns of different rice individuals. The genes exhibiting changes at the transcriptional and methylation levels varied among the different plants; however, these genes regulate consistent biological functions, primarily emphasizing metabolic processes. Finally, through single-sample analysis, we identified a set of miRNAs induced by lunar orbital stressors that potentially target DNA methylation regulatory factors. The findings of this study broaden the understanding of space biological effects and lay a foundation for further exploration of the mechanisms by which deep space flight impacts plants.

深空飞行会对生物有机体造成更严重的损伤，但其对水稻的具体影响尚不明确。为探究深空飞行环境下DNA甲基化（DNA methylation）的变化规律，本研究针对嫦娥五号（Chang’e-5）搭载的水稻种子开展了实验。经23天月球轨道飞行后，这些种子被种植于人工气候箱中，并在分蘖期与抽穗期分别进行转录组（transcriptome）与DNA甲基化测序。水稻基因组的甲基化模式在月球轨道胁迫因子作用下表现出差异性。DNA甲基化会改变功能基因的表达与互作模式，涉及代谢、防御等生物学过程。此外，本研究采用单样本分析方法，对不同水稻个体的基因表达与互作模式进行了评估。尽管不同植株间转录与甲基化水平发生改变的基因存在差异，但这些基因所调控的生物学功能却具有一致性，主要集中于代谢过程。最后，通过单样本分析，本研究鉴定出一组受月球轨道胁迫诱导的微小RNA（miRNAs），其潜在靶标为DNA甲基化调控因子。本研究结果拓宽了人们对空间生物效应的认知，为进一步探究深空飞行影响植物的分子机制奠定了基础。