Polkhovskiy Alexander, Komakhin Roman, Kirov Ilya
Moscow Center for Advanced Studies, Kulakova Str. 20, 123592 Moscow, Russia.
All-Russia Research Institute of Agricultural Biotechnology, Timiryazevskaya Str. 42, 127550 Moscow, Russia.
Plants (Basel). 2025 Jun 20;14(13):1894. doi: 10.3390/plants14131894.
LTR retrotransposons are widespread genomic elements that significantly impact genome structure and function. In , the EVD LTR retrotransposon encodes a GAG protein essential for retrotransposon particle assembly. Here, we present a comprehensive analysis of the structural features, intracellular localization, and transcriptomic effects of the EVD GAG (evdGAG) protein. Using AlphaFold3, we identified canonical capsid (CA-NTD and CA-CTD) and nucleocapsid (NC) domains, with predicted disordered regions likely facilitating oligomerization. Transient expression of GFP-tagged evdGAG in protoplasts of and distant plant species ( and ) revealed the formation of multiple large cytoplasmic aggregates resembling retrosomes, often localized near the nucleus. Stable overexpression of evdGAG in wild-type and mutant backgrounds induced significant transcriptomic changes, including up-regulation of stress response and defense-related genes and downregulation of photosynthesis and chloroplast-associated pathways. Importantly, genes linked to stress granule formation were also up-regulated, suggesting a role for evdGAG in modulating cellular stress responses. Our findings provide novel insights into the cellular and molecular properties of plant retrotransposon GAG proteins and their influence on host gene expression.
LTR逆转录转座子是广泛存在的基因组元件，对基因组结构和功能有重大影响。在[具体内容缺失]中，EVD LTR逆转录转座子编码一种对逆转录转座子颗粒组装至关重要的GAG蛋白。在此，我们对EVD GAG（evdGAG）蛋白的结构特征、细胞内定位和转录组效应进行了全面分析。使用AlphaFold3，我们鉴定出了典型的衣壳（CA-NTD和CA-CTD）和核衣壳（NC）结构域，预测的无序区域可能有助于寡聚化。在[具体植物物种1]和远缘植物物种（[具体植物物种2]和[具体植物物种3]）的原生质体中瞬时表达GFP标记的evdGAG，揭示了形成多个类似于逆转录体的大细胞质聚集体，这些聚集体通常位于细胞核附近。在野生型和[具体突变体]背景下稳定过表达evdGAG会引起显著的转录组变化，包括应激反应和防御相关基因的上调以及光合作用和叶绿体相关途径的下调。重要的是，与应激颗粒形成相关的基因也上调了，这表明evdGAG在调节细胞应激反应中发挥作用。我们的研究结果为植物逆转录转座子GAG蛋白的细胞和分子特性及其对宿主基因表达的影响提供了新的见解。
