Pereira Jovani Bernardino de Souza, Oliveira Renato Renison Moreira, Vasconcelos Santelmo, Dias Mariana Costa, Caldeira Cecílio Frois, Quandt Dietmar, Oliveira Guilherme, Prado Jefferson
Instituto de Pesquisas Ambientais (IPA), São Paulo, Brazil.
Bonner Institut für Organismische Biologie (BIOB), Abt. Biodiversität der Pflanzen, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.
Front Plant Sci. 2024 Mar 12;15:1298302. doi: 10.3389/fpls.2024.1298302. eCollection 2024.
RNA editing is a post-transcriptional process that challenges the central dogma of molecular biology by modifying RNA sequences, introducing nucleotide changes at specific sites, and generating functional diversity beyond the genomic code, especially when it concerns organellar transcripts. In plants, this phenomenon is widespread, but its extent varies significantly among species and organellar genomes. Among land plants, the heterosporous lycophytes (i.e., and ) stand out for their exceptionally high numbers of RNA-editing sites, despite their morphological stasis and ancient lineage. In this study, we explore the complete set of organellar protein-coding genes in the aquatic plant group , providing a detailed analysis of RNA editing in both the mitochondrial and plastid genomes. Our findings reveal a remarkable abundance of RNA editing, particularly in the mitochondrial genome, with thousands of editing sites identified. Interestingly, the majority of these edits result in non-silent substitutions, suggesting a role in fine-tuning protein structure and function. Furthermore, we observe a consistent trend of increased hydrophobicity in membrane-bound proteins, supporting the notion that RNA editing may confer a selective advantage by preserving gene functionality in . The conservation of highly edited RNA sequences over millions of years underscores the evolutionary significance of RNA editing. Additionally, the study sheds light on the dynamic nature of RNA editing, with shared editing sites reflecting common ancestry whereas exclusive edits matching more recent radiation events within the genus. This work advances our understanding of the intricate interplay between RNA editing, adaptation, and evolution in land plants and highlights the unique genomic features of , providing a foundation for further investigations into the functional consequences of RNA editing in this enigmatic plant lineage.
RNA编辑是一种转录后过程，它通过修饰RNA序列、在特定位点引入核苷酸变化以及产生超越基因组编码的功能多样性来挑战分子生物学的中心法则，尤其是在涉及细胞器转录本时。在植物中，这种现象很普遍，但在物种和细胞器基因组之间其程度差异很大。在陆地植物中，尽管形态停滞且谱系古老，但异孢石松类植物（即 和 ）因其异常高数量的RNA编辑位点而引人注目。在本研究中，我们探索了水生植物类群 中完整的细胞器蛋白质编码基因集，对线粒体和质体基因组中的RNA编辑进行了详细分析。我们的发现揭示了RNA编辑的显著丰富性，特别是在线粒体基因组中，鉴定出了数千个编辑位点。有趣的是，这些编辑中的大多数导致了非同义替换，表明其在微调蛋白质结构和功能方面发挥作用。此外，我们观察到膜结合蛋白中疏水性增加的一致趋势，支持了RNA编辑可能通过在 中保留基因功能而赋予选择优势的观点。数百万年来高度编辑的RNA序列的保守性强调了RNA编辑的进化意义。此外，该研究揭示了RNA编辑的动态性质，共享的编辑位点反映了共同祖先，而独特的编辑则与该属内最近的辐射事件相匹配。这项工作推进了我们对陆地植物中RNA编辑、适应和进化之间复杂相互作用的理解，并突出了 的独特基因组特征，为进一步研究这种神秘植物谱系中RNA编辑的功能后果奠定了基础。
