Nuclear-mitochondrial communication is crucial for plant growth, particularly in the context of cytoplasmic male sterility (CMS) repair mechanisms linked to mitochondrial genome mutations. The restorer of fertility-like (RFL) genes, known for their role in CMS restoration, remains largely unexplored in plant development. In this study, we focused on the evolutionary relationship of RFL family genes in poplar, specifically within the dioecious Salicaceae plants. PtoRFL30 was identified to be preferentially expressed in stem vasculature, suggesting a distinct correlation with vascular cambium development. Transgenic poplar plants overexpressing PtoRFL30 exhibited a profound inhibition of vascular cambial activity and xylem development. Conversely, RNA interference-mediated knockdown of PtoRFL30 led to increased wood formation. Importantly, we revealed that PtoRFL30 plays a crucial role in maintaining mitochondrial functional homeostasis. Treatment with mitochondrial activity inhibitors delayed wood development in PtoRFL30-RNAi transgenic plants. Further investigations unveiled significant variations in auxin accumulation levels within vascular tissues of PtoRFL30-transgenic plants. Wood development anomalies resulting from PtoRFL30-overexpression and -knockdown were rectified by NAA and NPA treatments, respectively. Our findings underscore the essential role of the PtoRFL30-mediated mitochondrion-auxin signaling module in wood formation, shedding light on the intricate nucleus-organelle communication during secondary vascular development.

中文翻译：

---

编码线粒体定位五肽重复蛋白的生育力恢复剂 30 调节杨树的木材形成


核线粒体通讯对于植物生长至关重要，特别是在与线粒体基因组突变相关的细胞质雄性不育（CMS）修复机制的背景下。类育性 (RFL) 基因的恢复因子以其在 CMS 恢复中的作用而闻名，但在植物发育过程中仍然很大程度上未被探索。在这项研究中，我们重点关注杨树中 RFL 家族基因的进化关系，特别是雌雄异株杨柳科植物中的进化关系。 PtoRFL30 被发现优先在茎脉管系统中表达，表明与维管形成层发育存在明显的相关性。过表达 PtoRFL30 的转基因杨植物表现出对维管形成层活性和木质部发育的深刻抑制。相反，RNA 干扰介导的 PtoRFL30 敲除导致木材形成增加。重要的是，我们发现 PtoRFL30 在维持线粒体功能稳态中发挥着至关重要的作用。线粒体活性抑制剂处理延迟了 PtoRFL30-RNAi 转基因植物的木材发育。进一步的研究揭示了 PtoRFL30 转基因植物维管组织内生长素积累水平的显着变化。 PtoRFL30 过度表达和敲低导致的木材发育异常分别通过 NAA 和 NPA 处理得到纠正。我们的研究结果强调了 PtoRFL30 介导的线粒体生长素信号模块在木材形成中的重要作用，揭示了次生血管发育过程中复杂的核-细胞器通讯。