Chen Lishan, Yang Qing, Zhang Yan, Sun Yeqing
Institute of Environmental Systems Biology, College of Environmental Science and Engineering, Dalian Maritime University, Dalian, China.
Front Plant Sci. 2025 Jan 8;15:1446383. doi: 10.3389/fpls.2024.1446383. eCollection 2024.
Rice samples exposed to the space environment have generated diverse phenotypic variations. Miniature-inverted-repeat transposable elements (MITEs), often found adjacent to genes, play a significant role in regulating the plant genome. Herein, the contribution of MITEs in regulating space-mutagenic phenotypes was explored.
The space-mutagenic phenotype changes in the F3 to F5 generations of three space-mutagenic lines from the rice varieties Dongnong423 (DN423) and Dongnong (DN416) were meticulously traced. Rice leaves samples at the heading stage from three space-mutagenic lines were subjected to high coverage whole-genome bisulfite sequencing and whole-genome sequencing. These analyses were conducted to investigate the effects of MITEs related epigenetic and genetic variations on space-mutagenic phenotypes.
Studies have indicated that MITEs within gene regulatory regions might contribute to the formation and differentiation of space-mutagenic phenotypes. The space environment has been shown to induce the transposable elements insertion polymorphisms of MITEs (MITEs-TIPs), with a notable preference for insertion near genes involved in stress response and phenotype regulation. The space-induced MITEs-TIPs contributed to the formation of space-mutagenic phenotype by modulating the expression of gene near the insertion site. This study underscored the pivotal role of MITEs in modulating plant phenotypic variation induced by the space environment, as well as the transgenerational stability of these phenotypic variants.
暴露于太空环境的水稻样本产生了多种表型变异。微型反向重复转座元件（MITEs）通常位于基因附近，在调控植物基因组中发挥着重要作用。在此，探讨了MITEs在调控太空诱变表型中的作用。
对水稻品种东农423（DN423）和东农416（DN416）的三个太空诱变品系从F3代到F5代的太空诱变表型变化进行了细致追踪。对三个太空诱变品系抽穗期的水稻叶片样本进行了高覆盖度全基因组亚硫酸氢盐测序和全基因组测序。进行这些分析以研究与MITEs相关的表观遗传和遗传变异对太空诱变表型的影响。
研究表明，基因调控区域内的MITEs可能有助于太空诱变表型的形成和分化。太空环境已被证明可诱导MITEs的转座元件插入多态性（MITEs-TIPs），且明显倾向于插入参与应激反应和表型调控的基因附近。太空诱导的MITEs-TIPs通过调节插入位点附近基因的表达，促进了太空诱变表型的形成。本研究强调了MITEs在调控太空环境诱导的植物表型变异中的关键作用，以及这些表型变异的跨代稳定性。
