Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, 80-307 Gdansk, Poland.
Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
Int J Mol Sci. 2021 Mar 16;22(6):3006. doi: 10.3390/ijms22063006.
possesses two acyl-CoA:lysophosphatidylethanolamine acyltransferases, LPEAT1 and LPEAT2, which are encoded by and genes, respectively. Both single mutant and double mutant plants exhibit a variety of conspicuous phenotypes, including dwarfed growth. Confocal microscopic analysis of tobacco suspension-cultured cells transiently transformed with green fluorescent protein-tagged versions of LPEAT1 or LPEAT2 revealed that LPEAT1 is localized to the endoplasmic reticulum (ER), whereas LPEAT2 is localized to both Golgi and late endosomes. Considering that the primary product of the reaction catalyzed by LPEATs is phosphatidylethanolamine, which is known to be covalently conjugated with autophagy-related protein ATG8 during a key step of the formation of autophagosomes, we investigated the requirements for LPEATs to engage in autophagic activity in Arabidopsis. Knocking out of either or both genes led to enhanced accumulation of the autophagic adaptor protein NBR1 and decreased levels of both mRNA and total ATG8 protein. Moreover, we detected significantly fewer membrane objects in the vacuoles of double mutant mesophyll cells than in vacuoles of control plants. However, contrary to what has been reported on autophagy deficient plants, the mutants displayed a prolonged life span compared to wild type, including delayed senescence.
它拥有两种酰基辅酶 A：溶血磷脂酰乙醇胺酰基转移酶（LPEAT1 和 LPEAT2），分别由 和 基因编码。单一 突变体和双 突变体植物均表现出多种明显的表型，包括生长矮小。用绿色荧光蛋白标记的 LPEAT1 或 LPEAT2 的瞬时转化的烟草悬浮细胞的共焦显微镜分析表明，LPEAT1 定位于内质网（ER），而 LPEAT2 则定位于高尔基体和晚期内体。考虑到 LPEATs 催化的反应的主要产物是磷脂酰乙醇胺，已知它在自噬体形成的关键步骤中与自噬相关蛋白 ATG8 共价结合，我们研究了 LPEATs 在拟南芥中参与自噬活性的要求。敲除 或 基因会导致自噬衔接蛋白 NBR1 的积累增加，以及 mRNA 和总 ATG8 蛋白水平的降低。此外，我们在 双突变体叶肉细胞的液泡中检测到的膜物体明显少于对照植物中的液泡。然而，与自噬缺陷植物的报道相反，与野生型相比， 突变体的寿命延长，包括衰老延迟。
