title: Ubiquitin-Proteasome System in ABA Signaling: From Perception to Action.
abstract: Protein post-translational modification (PTM) by ubiquitination has been observed during many aspects of plant growth, development, and stress responses. The ubiquitin-proteasome system precisely regulates phytohormone signaling by affecting protein activity, localization, assembly, and interaction ability. Abscisic acid (ABA) is a major phytohormone, and plays important roles in plants under normal or stressed growth conditions. The ABA signaling pathway is composed of phosphatases, kinases, transcription factors, and membrane ion channels. It has been reported that multiple ABA signaling transducers are subjected to the regulations by ubiquitination. In particular, recent studies have identified different types of E3 ligases that mediate ubiquitination of ABA receptors in different cell compartments. This review focuses on modulation of these components by monoubiquitination or polyubiquitination that occurs in the plasma membrane, endomembranes, and from the cytosol to the nucleus; this implies the existence of retrograde and trafficking processes that are regulated by ubiquitination in ABA signaling. A number of single-unit E3 ligases, components of multi-subunit E3 ligases, E2s, and specific subunits of the 26S proteasome involved in ABA signal regulation are discussed. Dissecting the precise functions of ubiquitination in the ABA pathway may help us understand key factors in the signaling of other phytohormones regulated by ubiquitination and other types of PTMs.
authors.affiliation: State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing 100101, P. R. China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing 100101, P. R. China.
authors.forename: Yaorong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing 100101, P. R. China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China. Electronic address: qxie@genetics.ac.cn.
authors.forename: Qi
authors.initials: Q
authors.lastname: Xie
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D015398:Signal Transduction; D025801:Ubiquitin / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D025801:Ubiquitin; D000040:Abscisic Acid; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex
keywords: ABA receptor; ABA signaling; E3 ligase; protein post-translational modification; transcription factor; ubiquitination