title: An Arabidopsis R2R3-MYB transcription factor, AtMYB20, negatively regulates type 2C serine/threonine protein phosphatases to enhance salt tolerance.
abstract: We have characterized the function of a plant R2R3-MYB transcription factor, Arabidopsis thaliana MYB20 (AtMYB20). Transgenic plants overexpressing AtMYB20 (AtMYB20-OX) enhanced salt stress tolerance while repression lines (AtMYB20-SRDX) were more vulnerable to NaCl than wild-type plants. Following NaCl treatment, the expressions of ABI1, ABI2 and AtPP2CA, which encode type 2C serine/threonine protein phosphatases (PP2Cs) that act as negative regulators in abscisic acid (ABA) signaling, were suppressed in AtMYB20-OX but induced in AtMYB20-SRDX. The electrophoretic mobility shift assay results revealed that AtMYB20 binds to the promoter regions containing the MYB recognition sequence (TAACTG) and an ACGT core element of ABI1 and AtPP2CA. These findings suggest that AtMYB20 down-regulates the expression of PP2Cs, the negative regulator of ABA signaling, and enhances salt tolerance.
authors: School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors: Mei Hua
authors: MH
authors: Cui
authors: Kyoung Shin
authors: KS
authors: Yoo
authors: Sujin
authors: S
authors: Hyoung
authors: Ha Thi Kim
authors: HT
authors: Nguyen
authors: Yun Young
authors: YY
authors: Kim
authors: Hae Jin
authors: HJ
authors: Kim
authors: Sung Han
authors: SH
authors: Ok
authors: Sang Dong
authors: SD
authors: Yoo
authors: Jeong Sheop
authors: JS
authors: Shin
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000222:Adaptation, Physiological / Q000235:genetics; D017360:Arabidopsis / Q000166:cytology / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D042541:Intracellular Space / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D000071636:Protein Phosphatase 2C; D021381:Protein Transport; D055049:Salt Tolerance / Q000235:genetics*; D036226:Seedlings / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C500589:Myb protein, Arabidopsis; D014157:Transcription Factors; D000040:Abscisic Acid; C087434:ABI1 protein, Arabidopsis; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C