title: RPN1a negatively regulates ABA signaling in Arabidopsis.
abstract: The 26S proteasome selectively regulates key abscisic acid (ABA) signaling proteins, but the physiological functions and mechanisms of RPN1a (a subunit of the 26S proteasome) in ABA signaling remain largely unknown. In this study, we found that the mRNA expression of RPN1a was suppressed by ABA treatment, and that RPN1a protein was expressed abundantly in guard cells. In the presence of ABA, rpn1a mutants showed rapid stomatal closure, low water loss, delayed germination, and inhibited root elongation. In addition, the transcripts of key ABA signaling genes, including ABI5, RD22, RD29A, and RD29B, were upregulated in rpn1a mutant plants in response to ABA. Furthermore, the ABI5 protein level was higher in rpn1a mutants subjected to ABA treatment. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that RPN1a interacts with ABI1. Overall, these findings suggest that RPN1a negatively regulates ABA signaling in Arabidopsis.
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Dashi
authors.initials: D
authors.lastname: Yu
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Xiushan
authors.initials: X
authors.lastname: Li
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Changqing
authors.initials: C
authors.lastname: Du
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Chen
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Chiyu
authors.initials: C
authors.lastname: Li
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Mengsi
authors.initials: M
authors.lastname: Sun
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Long
authors.initials: L
authors.lastname: Wang
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Lin
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Dongying
authors.initials: D
authors.lastname: Tang
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China. Electronic address: feng_yu@hnu.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Yu
authors.affiliation: Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, China. Electronic address: xmL05@hnu.edu.cn.
authors.forename: Xuanming
authors.initials: X
authors.lastname: Liu
mesh_terms: D000040:Abscisic Acid / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D009154:Mutation; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D054046:Plant Stomata / Q000378:metabolism; D030821:Plants, Genetically Modified; D015398:Signal Transduction
chemical_list: C409743:ABI5 protein, Arabidopsis; D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; C507997:RPN1 protein, Arabidopsis; D000040:Abscisic Acid; C087434:ABI1 protein, Arabidopsis; D010749:Phosphoprotein Phosphatases
keywords: 26S proteasome subunit; Abscisic acid; Arabidopsis thaliana; RPN1a