Many proteins used in industrial and pharmaceutical applications are typically synthesized within the secretory pathway. While yeast and mammalian cells have been engineered to enhance the production of endomembrane‐targeted proteins, similar strategies in plant cells remain underexplored. This study investigates the potential of arabidopsis leafy cotyledon 2 (AtLEC2), a key regulator of seed development, to enhance the production of proteins targeted to the endoplasmic reticulum (ER) in Nicotiana benthamiana leaves. Through transient expression experiments, we demonstrate that AtLEC2 selectively increases the production of ER‐targeted GUS without affecting its cytosolic variant. Moreover, leaves agroinfiltrated with AtLEC2 show a significant increase in ER‐GFP accumulation compared to controls lacking AtLEC2. Transcriptomic analysis reveals that AtLEC2 promotes ribosome and chloroplast biogenesis, along with the upregulation of genes involved in photosynthesis, translation, and membrane synthesis. Notably, seed‐specific poly(A) binding proteins involved in RNA stability and translation initiation, as well as 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase—linked to ER hypertrophy—are highly upregulated. This study establishes a novel connection between AtLEC2 and the enhancement of ER‐targeted foreign protein synthesis, paving the way for innovative strategies in plant cellular engineering.

中文翻译：

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AtLEC2 介导的本氏烟草叶片内质网靶向外源蛋白合成的增强：来自转录组学分析的见解


工业和制药应用中使用的许多蛋白质通常在分泌途径内合成。虽然酵母和哺乳动物细胞已被改造成可增强内膜靶向蛋白的产生，但植物细胞中的类似策略仍未得到充分探索。本研究调查了拟南芥叶子叶 2 （AtLEC2） 的潜力，该子叶是种子发育的关键调节因子，可增强本氏烟草叶片中靶向内质网 （ER） 的蛋白质的产生。通过瞬时表达实验，我们证明 AtLEC2 选择性地增加 ER 靶向 GUS 的产生，而不影响其胞质变体。此外，与缺乏 AtLEC2 的对照相比，用 AtLEC2 农艺浸润的叶片显示 ER-GFP 积累显着增加。转录组学分析显示，AtLEC2 促进核糖体和叶绿体生物发生，以及参与光合作用、翻译和膜合成的基因的上调。值得注意的是，参与 RNA 稳定性和翻译起始的种子特异性 poly（A） 结合蛋白，以及与 ER 肥大相关的 3-羟基-3-甲基戊二酰辅酶 A 还原酶高度上调。这项研究在 AtLEC2 与增强 ER 靶向外源蛋白合成之间建立了新的联系，为植物细胞工程的创新策略铺平了道路。