A plant-unique ESCRT component, FYVE4, regulates multivesicular endosome biogenesis and plant growth
A plant-unique ESCRT component, FYVE4, regulates multivesicular endosome biogenesis and plant growth
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FYVE4 是植物特有的 ESCRT 成分，可调节多囊泡内体生物发生和植物生长。
DOI：
10.1111/nph.17358
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发表时间：
2021-04-22
期刊：
影响因子：
9.4
通讯作者：
Gao, Caiji
中科院分区：
文献类型：
--
作者：
Liu, Chuanliang;Zeng, Yonglun;Gao, Caiji
在进化过程中，陆地植物产生了独特的蛋白质，参与内体分选和多泡内体（MVE）的生物发生，其中许多具有特定的磷酸肌醇结合能力。然而，大多数植物磷酸肌醇结合蛋白在内体运输中的功能仍然是难以捉摸的。在这里，我们分析了几个缺乏预测的磷酸肌醇结合蛋白的拟南芥突变体，并首次将fyve 4 -1鉴定为对高硼条件过敏的突变体，与SNF 7相互作用的含FYVE结构域的蛋白质，SNF 7是ESCRT-III（转运III所需的内体分选复合物）的核心组分。FYVE 4影响晚期作用ESCRT组分SNF 7和VPS 4的膜结合，并调节MVE内管腔内囊泡（ILV）的形成。FYVE 4在ESCRT途径中的关键功能通过与SNF 7 B和LIP 5的强遗传相互作用进一步证明。fyve 4 -1、snf 7 b和lip 5单突变体是活的，而fyve 4 -1 snf 7 b和fyve 4 -1 lip 5双突变体是致死的，在MVE的生物发生和泛素化膜蛋白的液泡分选方面存在严重缺陷。
During evolution, land plants generated unique proteins that participate in endosomal sorting and multivesicular endosome (MVE) biogenesis, many of them with specific phosphoinositide-binding capabilities. Nonetheless, the function of most plant phosphoinositide-binding proteins in endosomal trafficking remains elusive.Here, we analysed several Arabidopsis mutants lacking predicted phosphoinositide-binding proteins and first identified fyve4-1 as a mutant with a hypersensitive response to high-boron conditions and defects in degradative vacuolar sorting of membrane proteins such as the borate exporter BOR1-GFP.FYVE4 encodes a plant-unique, FYVE domain-containing protein that interacts with SNF7, a core component of ESCRT-III (Endosomal Sorting Complex Required for Transport III). FYVE4 affects the membrane association of the late-acting ESCRT components SNF7 and VPS4, and modulates the formation of intraluminal vesicles (ILVs) inside MVEs. The critical function of FYVE4 in the ESCRT pathway was further demonstrated by the strong genetic interactions with SNF7B and LIP5. Although the fyve4-1, snf7b and lip5 single mutants were viable, the fyve4-1 snf7b and fyve4-1 lip5 double mutants were seedling lethal, with strong defects in MVE biogenesis and vacuolar sorting of ubiquitinated membrane proteins.Taken together, we identified FYVE4 as a novel plant endosomal regulator, which functions in ESCRTing pathway to regulate MVE biogenesis.