title: Dual roles of an Arabidopsis ESCRT component FREE1 in regulating vacuolar protein transport and autophagic degradation.
abstract: Protein turnover can be achieved via the lysosome/vacuole and the autophagic degradation pathways. Evidence has accumulated revealing that efficient autophagic degradation requires functional endosomal sorting complex required for transport (ESCRT) machinery. However, the interplay between the ESCRT machinery and the autophagy regulator remains unclear. Here, we show that FYVE domain protein required for endosomal sorting 1 (FREE1), a recently identified plant-specific ESCRT component essential for multivesicular body (MVB) biogenesis and plant growth, plays roles both in vacuolar protein transport and autophagic degradation. FREE1 also regulates vacuole biogenesis in both seeds and vegetative cells of Arabidopsis. Additionally, FREE1 interacts directly with a unique plant autophagy regulator SH3 domain-containing protein2 and associates with the PI3K complex, to regulate the autophagic degradation in plants. Thus, FREE1 plays multiple functional roles in vacuolar protein trafficking and organelle biogenesis as well as in autophagic degradation via a previously unidentified regulatory mechanism of cross-talk between the ESCRT machinery and autophagy process.
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Caiji
authors.initials: C
authors.lastname: Gao
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Zhuang
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Yong
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Xi
authors.initials: X
authors.lastname: Fu
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Yilin
authors.initials: Y
authors.lastname: He
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Yonglun
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China;
authors.forename: Jinbo
authors.initials: J
authors.lastname: Shen
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; and.
authors.forename: Ming
authors.initials: M
authors.lastname: Luo
authors.affiliation: Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China ljiang@cuhk.edu.hk.
authors.forename: Liwen
authors.initials: L
authors.lastname: Jiang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001343:Autophagy / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D056827:Endosomal Sorting Complexes Required for Transport / Q000378:metabolism*; D031541:Fluorescence Resonance Energy Transfer; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D057146:Multivesicular Bodies / Q000378:metabolism*; D038761:Photobleaching; D021381:Protein Transport / Q000235:genetics / Q000502:physiology; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D056827:Endosomal Sorting Complexes Required for Transport; C000597558:FREE1 protein, Arabidopsis; C000597559:SH3P2 protein, Arabidopsis; D033921:Vesicular Transport Proteins
keywords: ESCRT machinery; FREE1; FYVE domain; autophagic degradation; vacuole biogenesis