title: Arabidopsis Tóxicos en Levadura 78 (AtATL78) mediates ABA-dependent ROS signaling in response to drought stress.
abstract: Plants have developed a variety of complicated responses to cope with drought, one of the most challenging environmental stresses. As a quick response, plants rapidly inhibit stomatal opening under the control of abscisic acid (ABA) signaling pathway, in order to preserve water. Here, we report that Arabidopsis Tóxicos en Levadura (ATL), a RING-type E3 ubiquitin ligase, mediates the ABA-dependent stomatal closure. In contrast to wild-type plants, the stomatal closure was fully impaired in atatl78 mutant plants even in the presence of exogenous ABA and reactive oxygen species (ROS). Besides, under high concentrations of Ca(2+), a down-stream signaling molecule of ABA signaling pathway, atatl78 mutant plants successfully closed the pores. Furthermore, AtATL78 protein indirectly associated with catalases and the deficiency of AtATL78 led the reduction of catalase activity and H2O2, implying the function of AtATL78 in the modulation of ROS activity. Based on these results, we suggest that AtATL78 possibly plays a role in promoting ROS-mediated ABA signaling pathway during drought stress.
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Suh
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Tae Rin
authors.initials: TR
authors.lastname: Oh
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Seok Keun
authors.initials: SK
authors.lastname: Cho
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea; Section of Plant Biochemistry, Department of Plant and Environmental Sciences, Faculty of Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark. Electronic address: swyang@plen.ku.dk.
authors.forename: Seong Wook
authors.initials: SW
authors.lastname: Yang
authors.affiliation: Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea. Electronic address: wtkim@yonsei.ac.kr.
authors.forename: Woo Taek
authors.initials: WT
authors.lastname: Kim
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000222:Adaptation, Physiological / Q000502:physiology; D017360:Arabidopsis / Q000502:physiology*; D055864:Droughts; D015398:Signal Transduction / Q000502:physiology*; D013312:Stress, Physiological / Q000502:physiology*; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*
chemical_list: D000040:Abscisic Acid; D044767:Ubiquitin-Protein Ligases
keywords: ABA-dependent signaling; Arabidopsis Tóxicos en Levadura (ATL); Drought stress; RING-type E3 ligase (RING); Reactive oxygen species (ROS); Ubiquitin-proteasome system (UPS)