Larran Alvaro Santiago, Ge Jingyu, Martín Guiomar, De la Concepción Juan Carlos, Dagdas Yasin, Qüesta Julia Irene
Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, 08193 Barcelona, Spain.
Plant Commun. 2025 Jan 13;6(1):101180. doi: 10.1016/j.xplc.2024.101180. Epub 2024 Oct 31.
Dynamic shuttling of proteins between the nucleus and cytoplasm orchestrates vital functions in eukaryotes. Here, we reveal the multifaceted functions of Arabidopsis Sin3-associated protein 18 kDa (SAP18) in the regulation of development and heat-stress tolerance. Proteomic analysis demonstrated that SAP18 is a core component of the nuclear apoptosis- and splicing-associated protein (ASAP) complex in Arabidopsis, contributing to the precise splicing of genes associated with leaf development. Genetic analysis further confirmed the critical role of SAP18 in different developmental processes as part of the ASAP complex, including leaf morphogenesis and flowering time. Interestingly, upon heat shock, SAP18 translocates from the nucleus to cytoplasmic stress granules and processing bodies. The heat-sensitive phenotype of a SAP18 loss-of-function mutant revealed a novel role for SAP18 in plant thermoprotection. These findings significantly expand our understanding of the relevance of SAP18 for plant growth, linking nuclear splicing with cytoplasmic stress responses and providing new perspectives for future exploration of plant thermotolerance mechanisms.
蛋白质在细胞核与细胞质之间的动态穿梭协调着真核生物的重要功能。在此，我们揭示了拟南芥Sin3相关蛋白18千道尔顿（SAP18）在发育调控和热胁迫耐受性方面的多方面功能。蛋白质组学分析表明，SAP18是拟南芥核凋亡和剪接相关蛋白（ASAP）复合物的核心成分，有助于与叶片发育相关基因的精确剪接。遗传分析进一步证实了SAP18作为ASAP复合物的一部分在不同发育过程中的关键作用，包括叶片形态发生和开花时间。有趣的是，热激时，SAP18从细胞核转移到细胞质应激颗粒和加工体。SAP18功能缺失突变体的热敏感表型揭示了SAP18在植物热保护中的新作用。这些发现显著扩展了我们对SAP18与植物生长相关性的理解，将核剪接与细胞质应激反应联系起来，并为未来探索植物耐热机制提供了新的视角。
