NDH expression marks major transitions in plant evolution and reveals coordinate intracellular gene loss

Background: Key innovations have facilitated novel niche utilization, such as the movement of the algal predecessors of land plants into terrestrial habitats where drastic fluctuations in light intensity, ultraviolet radiation and water limitation required a number of adaptations. The NDH (NADH dehydrogenase-like) complex of Viridiplantae plastids participates in adapting the photosynthetic response to environmental stress, suggesting its involvement in the transition to terrestrial habitats. Although relatively rare, the loss or pseudogenization of plastid NDH genes is widely distributed across diverse lineages of photoautotrophic seed plants and mutants/transgenics lacking NDH function demonstrate little difference from wild type under non-stressed conditions. This study analyzes large transcriptomic and genomic datasets to evaluate the persistence and loss of NDH expression across plants. Results: Nuclear expression profiles showed accretion of the NDH gene complement at key transiti...

研究背景：多项演化关键创新推动了全新生态位的开拓利用，例如陆生植物的藻类祖先向陆地生境的迁移——陆地生境中光照强度、紫外线辐射与水分限制均存在剧烈波动，这要求生物演化出一系列适应性机制。绿色植物亚界（Viridiplantae）质体中的NDH（烟酰胺腺嘌呤二核苷酸脱氢酶样，NADH dehydrogenase-like）复合物参与调控光合响应以适应环境胁迫，提示其在植物向陆地生境的过渡过程中发挥作用。尽管质体NDH基因的丢失或假基因化现象相对罕见，但该事件广泛分布于光合自养种子植物的多个演化支系中；且在非胁迫环境下，缺失NDH功能的突变体/转基因植株与野生型表型并无显著差异。本研究通过分析大规模转录组与基因组数据集，评估了NDH基因表达在植物类群中的留存与丢失情况。研究结果：核基因表达谱分析显示，在关键演化过渡节点处，NDH基因组分呈现积累趋势……