在巨自噬中,溶酶体与封闭的自噬体融合,但不与未封闭的自噬体融合。这是实现的,至少在某种程度上,通过时间调节的自噬体SNARESTX17(突触蛋白17)募集到成熟的自噬体。然而,STX17识别自噬体成熟的分子机制尚不清楚.我们最近的研究表明,STX17的募集受STX17的带正电的C末端区域和自噬小体膜之间的静电相互作用的调节。由于磷脂酰肌醇-4-磷酸(PtdIns4P)的积累,在成熟过程中带负电荷。这里,我们提出了自噬体的静电成熟模型。
In macroautophagy, lysosomes fuse with closed autophagosomes but not with unclosed ones. This is achieved, at least in part, by the temporally regulated recruitment of the autophagosomal SNARE STX17 (syntaxin 17) to only mature autophagosomes. However, the molecular mechanism by which STX17 recognizes autophagosomal maturation remains unknown. Our recent study revealed that STX17 recruitment is regulated by the electrostatic interaction between the positively charged C-terminal region of STX17 and the autophagosomal membrane, which becomes negatively charged during maturation due to the accumulation of phosphatidylinositol-4-phosphate (PtdIns4P). Here, we propose an electrostatic maturation model of the autophagosome.