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Kang NY, Kim MJ, Jeong S, Moon SY, Kim JS, Jeon J, Lee B, Lee MR, Kim J. HIGH PLOIDY2-mediated SUMOylation of transcription factor ARR1 controls two-component signaling in Arabidopsis. THE PLANT CELL 2024; 36:3521-3542. [PMID: 38819329 PMCID: PMC11371144 DOI: 10.1093/plcell/koae164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 04/23/2024] [Accepted: 04/28/2024] [Indexed: 06/01/2024]
Abstract
Cytokinins regulate plant growth, development, and responses to environmental stresses such as cold via phosphorelay from cytokinin receptors to the ARABIDOPSIS RESPONSE REGULATORs (ARRs). However, the molecular mechanisms underlying the activation of type-B ARR transcriptional activity in Arabidopsis (Arabidopsis thaliana) remain unclear. Here, we show that the E3 SUMO ligase HIGH PLOIDY2 SUMOylates ARR1, a type-B ARR, at K236, triggering its activation. Cold- or cytokinin-induced phosphorylation of ARR1 at D89 is crucial for its interaction with HPY2. Lysine 236 is critical for ARR1's transactivation without compromising its DNA-binding ability, while D89 is crucial for ARR1's binding to target gene promoters. Cytokinin enhances ARR1's chromatin binding, but cold does not. ARR1 K236 plays a critical role in promoting histone H3 acetylation in response to both cytokinin and cold without affecting chromatin binding. The K236R mutation in ARR1 reduces target gene expression and alters cytokinin and cold response phenotypes. This study unveils a mechanism of ARR1 activation wherein phosphorylated ARR1 interacts with HPY2 and binds to chromatin in response to cytokinin. Cold triggers a phosphorelay targeting chromatin-bound ARR1. HPY2 then catalyzes ARR1 SUMOylation at K236, enhancing histone H3 acetylation and leading to transcriptional activation of ARR1 in response to both cold and cytokinin.
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Affiliation(s)
- Na Young Kang
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Min-Jung Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Seon Jeong
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Sun Young Moon
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Jin Sun Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Jin Jeon
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Boyoung Lee
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Mi Rha Lee
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
| | - Jungmook Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Korea
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Korea
- Kumho Life Science Laboratory, Chonnam National University, Buk-Gu, Gwangju 61186, Korea
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2
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Kato Y, Konishi M. A mature liquid fertilizer derived from cattle urine promotes Arabidopsis thaliana growth via hormone-like responses. Biosci Biotechnol Biochem 2024; 88:1007-1018. [PMID: 38849314 DOI: 10.1093/bbb/zbae080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 06/01/2024] [Indexed: 06/09/2024]
Abstract
To understand the fertilization effects of liquid fertilizer (LF) produced by aerobic microbial processing of cattle urine, we investigated the influence of LF on growth and shoot genetic responses of the model plant Arabidopsis thaliana. LF significantly enhanced both shoot and root growth under aseptic conditions. Although filtrate from ultrafiltration (molecular weight cutoff: 10 000) also promoted shoot growth and root elongation, the concentrate only promoted root growth. Multiple growth-promoting factors were therefore associated with the growth promotion. Transcriptome analysis of shoots following LF addition identified 353 upregulated and 512 downregulated genes. According to gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses, signal transduction of a phytohormone cytokinin was influenced by LF addition. Cytochrome P450 induction triggered the related signal transitions, and would introduce the growth promotion for shoot. Primary auxin responses and abscisic acid signaling responses were also observed in the presence of LF. Ethylene signaling seemed to be insensitive.
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Affiliation(s)
- Yuta Kato
- Kankyo Daizen Co., Ltd, Hokkaido, Japan
- Cold Regions, Environmental and Energy Engineering Course, Graduate School of Engineering, Kitami Institute of Technology, Hokkaido, Japan
| | - Masaaki Konishi
- Department of Applied Chemistry, Kitami Institute of Technology, Hokkaido, Japan
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3
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Zhao J, Wang J, Liu J, Zhang P, Kudoyarova G, Liu CJ, Zhang K. Spatially distributed cytokinins: Metabolism, signaling, and transport. PLANT COMMUNICATIONS 2024; 5:100936. [PMID: 38689499 PMCID: PMC11287186 DOI: 10.1016/j.xplc.2024.100936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 04/25/2024] [Accepted: 04/28/2024] [Indexed: 05/02/2024]
Abstract
Cytokinins are mobile phytohormones that regulate plant growth, development, and environmental adaptability. The major cytokinin species include isopentenyl adenine (iP), trans-zeatin (tZ), cis-zeatin (cZ), and dihydrozeatin (DZ). The spatial distributions of different cytokinin species in different organelles, cells, tissues, and organs are primarily shaped by biosynthesis via isopentenyltransferases (IPT), cytochrome P450 monooxygenase, and 5'-ribonucleotide phosphohydrolase and by conjugation or catabolism via glycosyltransferase or cytokinin oxidase/dehydrogenase. Cytokinins bind to histidine receptor kinases in the endoplasmic reticulum or plasma membrane and relay signals to response regulators in the nucleus via shuttle proteins known as histidine phosphotransfer proteins. The movements of cytokinins from sites of biosynthesis to sites of signal perception usually require long-distance, intercellular, and intracellular transport. In the past decade, ATP-binding cassette (ABC) transporters, purine permeases (PUP), AZA-GUANINE RESISTANT (AZG) transporters, equilibrative nucleoside transporters (ENT), and Sugars Will Eventually Be Exported transporters (SWEET) have been characterized as involved in cytokinin transport processes. This review begins by introducing the spatial distributions of various cytokinins and the subcellular localizations of the proteins involved in their metabolism and signaling. Highlights focus on an inventory of the characterized transporters involved in cytokinin compartmentalization, including long-distance, intercellular, and intracellular transport, and the regulation of the spatial distributions of cytokinins by environmental cues. Future directions for cytokinin research are also discussed.
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Affiliation(s)
- Jiangzhe Zhao
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Jingqi Wang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Jie Liu
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Penghong Zhang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China
| | - Guzel Kudoyarova
- Ufa Institute of Biology, Ufa Federal Research Center, RAS, Prospekt Oktyabrya 69, Ufa 450054, Russia
| | - Chang-Jun Liu
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Kewei Zhang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, P.R. China.
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4
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Argueso CT, Kieber JJ. Cytokinin: From autoclaved DNA to two-component signaling. THE PLANT CELL 2024; 36:1429-1450. [PMID: 38163638 PMCID: PMC11062471 DOI: 10.1093/plcell/koad327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/25/2023] [Accepted: 11/03/2023] [Indexed: 01/03/2024]
Abstract
Since its first identification in the 1950s as a regulator of cell division, cytokinin has been linked to many physiological processes in plants, spanning growth and development and various responses to the environment. Studies from the last two and one-half decades have revealed the pathways underlying the biosynthesis and metabolism of cytokinin and have elucidated the mechanisms of its perception and signaling, which reflects an ancient signaling system evolved from two-component elements in bacteria. Mutants in the genes encoding elements involved in these processes have helped refine our understanding of cytokinin functions in plants. Further, recent advances have provided insight into the mechanisms of intracellular and long-distance cytokinin transport and the identification of several proteins that operate downstream of cytokinin signaling. Here, we review these processes through a historical lens, providing an overview of cytokinin metabolism, transport, signaling, and functions in higher plants.
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Affiliation(s)
- Cristiana T Argueso
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Joseph J Kieber
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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5
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Zhou CM, Li JX, Zhang TQ, Xu ZG, Ma ML, Zhang P, Wang JW. The structure of B-ARR reveals the molecular basis of transcriptional activation by cytokinin. Proc Natl Acad Sci U S A 2024; 121:e2319335121. [PMID: 38198526 PMCID: PMC10801921 DOI: 10.1073/pnas.2319335121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Accepted: 12/11/2023] [Indexed: 01/12/2024] Open
Abstract
The phytohormone cytokinin has various roles in plant development, including meristem maintenance, vascular differentiation, leaf senescence, and regeneration. Prior investigations have revealed that cytokinin acts via a phosphorelay similar to the two-component system by which bacteria sense and respond to external stimuli. The eventual targets of this phosphorelay are type-B ARABIDOPSIS RESPONSE REGULATORS (B-ARRs), containing the conserved N-terminal receiver domain (RD), middle DNA binding domain (DBD), and C-terminal transactivation domain. While it has been established for two decades that the phosphoryl transfer from a specific histidyl residue in ARABIDOPSIS HIS PHOSPHOTRANSFER PROTEINS (AHPs) to an aspartyl residue in the RD of B-ARRs results in a rapid transcriptional response to cytokinin, the underlying molecular basis remains unclear. In this work, we determine the crystal structures of the RD-DBD of ARR1 (ARR1RD-DBD) as well as the ARR1DBD-DNA complex from Arabidopsis. Analyses of the ARR1DBD-DNA complex have revealed the structural basis for sequence-specific recognition of the GAT trinucleotide by ARR1. In particular, comparing the ARR1RD-DBD and ARR1DBD-DNA structures reveals that unphosphorylated ARR1RD-DBD exists in a closed conformation with extensive contacts between the RD and DBD. In vitro and vivo functional assays have further suggested that phosphorylation of the RD weakens its interaction with DBD, subsequently permits the DNA binding capacity of DBD, and promotes the transcriptional activity of ARR1. Our findings thus provide mechanistic insights into phosphorelay activation of gene transcription in response to cytokinin.
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Affiliation(s)
- Chuan-Miao Zhou
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
| | - Jian-Xu Li
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai201602, China
| | - Tian-Qi Zhang
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
| | - Zhou-Geng Xu
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
| | - Miao-Lian Ma
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
| | - Peng Zhang
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
- Key Laboratory of Plant Carbon Capture, Chinese Academy of Sciences, Shanghai200032, China
| | - Jia-Wei Wang
- National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai200032, China
- Key Laboratory of Plant Carbon Capture, Chinese Academy of Sciences, Shanghai200032, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai201210, China
- New Cornerstone Science Laboratory, Shanghai200032, China
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6
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Powell AE, Heyl A. The origin and early evolution of cytokinin signaling. FRONTIERS IN PLANT SCIENCE 2023; 14:1142748. [PMID: 37457338 PMCID: PMC10338860 DOI: 10.3389/fpls.2023.1142748] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 05/23/2023] [Indexed: 07/18/2023]
Abstract
Angiosperms, especially Arabidopsis and rice, have long been at the center of plant research. However, technological advances in sequencing have led to a dramatic increase in genome and transcriptome data availability across land plants and, more recently, among green algae. These data allowed for an in-depth study of the evolution of different protein families - including those involved in the metabolism and signaling of phytohormones. While most early studies on phytohormone evolution were phylogenetic, those studies have started to be complemented by genetic and biochemical studies in recent years. Examples of such functional analyses focused on ethylene, jasmonic acid, abscisic acid, and auxin. These data have been summarized recently. In this review, we will focus on the progress in our understanding of cytokinin biology. We will use these data to synthesize key points about the evolution of cytokinin metabolism and signaling, which might apply to the evolution of other phytohormones as well.
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Affiliation(s)
| | - Alexander Heyl
- Department of Research and Development, Garden City, NY, United States
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7
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Liu H, Huang J, Zhang X, Liu G, Liang W, Zhu G, Dong M, Li M, Zhang J, Yang W, Xiao W, Cheung AY, Tao LZ. The RAC/ROP GTPase activator OsRopGEF10 functions in crown root development by regulating cytokinin signaling in rice. THE PLANT CELL 2023; 35:453-468. [PMID: 36190337 PMCID: PMC9806555 DOI: 10.1093/plcell/koac297] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 09/28/2022] [Indexed: 05/26/2023]
Abstract
RAC/Rho of plant (ROP) GTPases are major molecular switches that control diverse signaling cascades for plant growth, development, and defense. Here, we discovered a signaling node that connects RAC/ROPs to cytokinins. Rice (Oryza sativa) plants develop a fibrous root system mainly composed of crown roots. Cytokinin signaling via a phosphorelay system is critical for crown root development. We show that OsRopGEF10, which activates RAC/ROPs, acts upstream of the cytoplasmic-nuclear shuttling phosphotransfer proteins AHPs of the cytokinin signaling pathway to promote crown root development. Mutations of OsRopGEF10 induced hypersensitivity to cytokinin, whereas overexpressing this gene reduced the cytokinin response. Loss of OsRopGEF10 function reduced the expression of the response regulator gene OsRR6, a repressor of cytokinin signaling, and impaired crown root development. Mutations in OsAHP1/2 led to increased crown root production and rescued the crown root defect of Osropgef10. Furthermore, auxin activates the ROP GTPase OsRAC3, which attenuates cytokinin signaling for crown root initiation. Molecular interactions between OsRopGEF10, OsRAC3, and OsAHP1/2 implicate a mechanism whereby OsRopGEF10-activated OsRAC3 recruits OsAHP1/2 to the cortical cytoplasm, sequestering them from their phosphorelay function in the nucleus. Together, our findings uncover the OsRopGEF10-OsRAC3-OsAHP1/2 signaling module, establish a link between RAC/ROPs and cytokinin, and reveal molecular crosstalk between auxin and cytokinin during crown root development.
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Affiliation(s)
- Huili Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Jiaqing Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Xiaojing Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Guolan Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Wei Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Guangqi Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Mengge Dong
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Ming Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Jie Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Weiyuan Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Wu Xiao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Alice Y Cheung
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Li-Zhen Tao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
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8
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Zhao L, Sun L, Guo L, Lu X, Malik WA, Chen X, Wang D, Wang J, Wang S, Chen C, Nie T, Ye W. Systematic analysis of Histidine photosphoto transfer gene family in cotton and functional characterization in response to salt and around tolerance. BMC PLANT BIOLOGY 2022; 22:548. [PMID: 36443680 PMCID: PMC9703675 DOI: 10.1186/s12870-022-03947-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Phosphorylation regulated by the two-component system (TCS) is a very important approach signal transduction in most of living organisms. Histidine phosphotransfer (HP) is one of the important members of the TCS system. Members of the HP gene family have implications in plant stresses tolerance and have been deeply studied in several crops. However, upland cotton is still lacking with complete systematic examination of the HP gene family. RESULTS A total of 103 HP gene family members were identified. Multiple sequence alignment and phylogeny of HPs distributed them into 7 clades that contain the highly conserved amino acid residue "XHQXKGSSXS", similar to the Arabidopsis HP protein. Gene duplication relationship showed the expansion of HP gene family being subjected with whole-genome duplication (WGD) in cotton. Varying expression profiles of HPs illustrates their multiple roles under altering environments particularly the abiotic stresses. Analysis is of transcriptome data signifies the important roles played by HP genes against abiotic stresses. Moreover, protein regulatory network analysis and VIGS mediated functional approaches of two HP genes (GhHP23 and GhHP27) supports their predictor roles in salt and drought stress tolerance. CONCLUSIONS This study provides new bases for systematic examination of HP genes in upland cotton, which formulated the genetic makeup for their future survey and examination of their potential use in cotton production.
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Affiliation(s)
- Lanjie Zhao
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Liangqing Sun
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
- Cotton Research Institute of Jiangxi Province, Jiujiang, Jiangxi, 332105, China
| | - Lixue Guo
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Xuke Lu
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Waqar Afzal Malik
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Xiugui Chen
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Delong Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Junjuan Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Shuai Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Chao Chen
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China
| | - Taili Nie
- Cotton Research Institute of Jiangxi Province, Jiujiang, Jiangxi, 332105, China.
| | - Wuwei Ye
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences / Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Anyang, Henan, 455000, China.
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9
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Anami S, Yamashino T, Suzuki R, Nakai K, Sato K, Wu B, Ryo M, Sugita M, Aoki S. Red light-regulated interaction of Per-Arnt-Sim histidine kinases with partner histidine-containing phosphotransfer proteins in Physcomitrium patens. Genes Cells 2021; 26:698-713. [PMID: 34086383 DOI: 10.1111/gtc.12878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 05/24/2021] [Accepted: 06/02/2021] [Indexed: 11/29/2022]
Abstract
Multi-step phosphorelay (MSP) is a broadly distributed signaling system in organisms. In MSP, histidine kinases (HKs) receive various environmental signals and transmit them by autophosphorylation followed by phosphotransfer to partner histidine-containing phosphotransfer proteins (HPts). Previously, we reported that Per-Arnt-Sim (PAS) domain-containing HK1 (PHK1) and PHK2 of the moss Physcomitrium (Physcomitrella) patens repressed red light-induced protonema branching, a critical step in the moss life cycle. In plants, PHK homolog-encoding genes are conserved only in early-diverging lineages such as bryophytes and lycophytes. PHKs-mediated signaling machineries attract attention especially from an evolutionary viewpoint, but they remain uninvestigated. Here, we studied the P. patens PHKs focusing on their subcellular patterns of localization and interaction with HPts. Yeast two-hybrid analysis, a localization assay with a green fluorescent protein, and a bimolecular fluorescence complementation analysis together showed that PHKs are localized and interact with partner HPts mostly in the nucleus, as unprecedented features for plant HKs. Additionally, red light triggered the interactions between PHKs and HPts in the cytoplasm, and light co-repressed the expression of PHK1 and PHK2 as well as genes encoding their partner HPts. Our results emphasize the uniqueness of PHKs-mediated signaling machineries, and functional implications of this uniqueness are discussed.
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Affiliation(s)
- Shu Anami
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | | | - Ryo Suzuki
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Kota Nakai
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Kensuke Sato
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Bowen Wu
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Masashi Ryo
- Graduate School of Information Science, Nagoya University, Nagoya, Japan
| | - Mamoru Sugita
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Setsuyuki Aoki
- Graduate School of Informatics, Nagoya University, Nagoya, Japan
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10
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Sound Waves Promote Arabidopsis thaliana Root Growth by Regulating Root Phytohormone Content. Int J Mol Sci 2021; 22:ijms22115739. [PMID: 34072151 PMCID: PMC8199107 DOI: 10.3390/ijms22115739] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 01/14/2023] Open
Abstract
Sound waves affect plants at the biochemical, physical, and genetic levels. However, the mechanisms by which plants respond to sound waves are largely unknown. Therefore, the aim of this study was to examine the effect of sound waves on Arabidopsis thaliana growth. The results of the study showed that Arabidopsis seeds exposed to sound waves (100 and 100 + 9k Hz) for 15 h per day for 3 day had significantly longer root growth than that in the control group. The root length and cell number in the root apical meristem were significantly affected by sound waves. Furthermore, genes involved in cell division were upregulated in seedlings exposed to sound waves. Root development was affected by the concentration and activity of some phytohormones, including cytokinin and auxin. Analysis of the expression levels of genes regulating cytokinin and auxin biosynthesis and signaling showed that cytokinin and ethylene signaling genes were downregulated, while auxin signaling and biosynthesis genes were upregulated in Arabidopsis exposed to sound waves. Additionally, the cytokinin and auxin concentrations of the roots of Arabidopsis plants increased and decreased, respectively, after exposure to sound waves. Our findings suggest that sound waves are potential agricultural tools for improving crop growth performance.
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Singh D, Gupta P, Singla-Pareek SL, Siddique KH, Pareek A. The Journey from Two-Step to Multi-Step Phosphorelay Signaling Systems. Curr Genomics 2021; 22:59-74. [PMID: 34045924 PMCID: PMC8142344 DOI: 10.2174/1389202921666210105154808] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/21/2020] [Accepted: 12/18/2020] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The two-component signaling (TCS) system is an important signal transduction machinery in prokaryotes and eukaryotes, excluding animals, that uses a protein phosphorylation mechanism for signal transmission. CONCLUSION Prokaryotes have a primitive type of TCS machinery, which mainly comprises a membrane-bound sensory histidine kinase (HK) and its cognate cytoplasmic response regulator (RR). Hence, it is sometimes referred to as two-step phosphorelay (TSP). Eukaryotes have more sophisticated signaling machinery, with an extra component - a histidine-containing phosphotransfer (HPT) protein that shuttles between HK and RR to communicate signal baggage. As a result, the TSP has evolved from a two-step phosphorelay (His-Asp) in simple prokaryotes to a multi-step phosphorelay (MSP) cascade (His-Asp-His-Asp) in complex eukaryotic organisms, such as plants, to mediate the signaling network. This molecular evolution is also reflected in the form of considerable structural modifications in the domain architecture of the individual components of the TCS system. In this review, we present TCS system's evolutionary journey from the primitive TSP to advanced MSP type across the genera. This information will be highly useful in designing the future strategies of crop improvement based on the individual members of the TCS machinery.
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Affiliation(s)
| | | | | | | | - Ashwani Pareek
- Address correspondence to this author at the Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India; Tel/Fax: 91-11-26704504 / 26742558; E-mail:
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Huo R, Liu Z, Yu X, Li Z. The Interaction Network and Signaling Specificity of Two-Component System in Arabidopsis. Int J Mol Sci 2020; 21:ijms21144898. [PMID: 32664520 PMCID: PMC7402358 DOI: 10.3390/ijms21144898] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 01/25/2023] Open
Abstract
Two-component systems (TCS) in plants have evolved into a more complicated multi-step phosphorelay (MSP) pathway, which employs histidine kinases (HKs), histidine-containing phosphotransfer proteins (HPts), and response regulators (RRs) to regulate various aspects of plant growth and development. How plants perceive the external signals, then integrate and transduce the secondary signals specifically to the desired destination, is a fundamental characteristic of the MSP signaling network. The TCS elements involved in the MSP pathway and molecular mechanisms of signal transduction have been best understood in the model plant Arabidopsis thaliana. In this review, we focus on updated knowledge on TCS signal transduction in Arabidopsis. We first present a brief description of the TCS elements; then, the protein–protein interaction network is established. Finally, we discuss the possible molecular mechanisms involved in the specificity of the MSP signaling at the mRNA and protein levels.
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Affiliation(s)
- Ruxue Huo
- Institute of Integrative Plant Biology, Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China;
- College of Agriculture and Forestry Sciences, Linyi University, Linyi 276000, China
| | - Zhenning Liu
- College of Agriculture and Forestry Sciences, Linyi University, Linyi 276000, China
- Correspondence: (Z.L.); (Z.L.)
| | - Xiaolin Yu
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Zongyun Li
- Institute of Integrative Plant Biology, Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China;
- Correspondence: (Z.L.); (Z.L.)
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New Insights into Multistep-Phosphorelay (MSP)/ Two-Component System (TCS) Regulation: Are Plants and Bacteria that Different? PLANTS 2019; 8:plants8120590. [PMID: 31835810 PMCID: PMC6963811 DOI: 10.3390/plants8120590] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 11/27/2019] [Accepted: 12/07/2019] [Indexed: 12/12/2022]
Abstract
The Arabidopsis multistep-phosphorelay (MSP) is a signaling mechanism based on a phosphorelay that involves three different types of proteins: Histidine kinases, phosphotransfer proteins, and response regulators. Its bacterial equivalent, the two-component system (TCS), is the most predominant device for signal transduction in prokaryotes. The TCS has been extensively studied and is thus generally well-understood. In contrast, the MSP in plants was first described in 1993. Although great advances have been made, MSP is far from being completely comprehended. Focusing on the model organism Arabidopsis thaliana, this review summarized recent studies that have revealed many similarities with bacterial TCSs regarding how TCS/MSP signaling is regulated by protein phosphorylation and dephosphorylation, protein degradation, and dimerization. Thus, comparison with better-understood bacterial systems might be relevant for an improved study of the Arabidopsis MSP.
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Wallmeroth N, Jeschke D, Slane D, Nägele J, Veerabagu M, Mira-Rodado V, Berendzen KW. ARR22 overexpression can suppress plant Two-Component Regulatory Systems. PLoS One 2019; 14:e0212056. [PMID: 30742656 PMCID: PMC6370222 DOI: 10.1371/journal.pone.0212056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/26/2019] [Indexed: 12/13/2022] Open
Abstract
In plants, several developmental processes are co-coordinated by cytokinins via phosphorylation dependent processes of the Two-Component System (TCS). An outstanding challenge is to track phosphorelay flow from cytokinin perception to its molecular outputs, of which gene activation plays a major role. To address this issue, a kinetic-based reporter system was expounded to track TCS phosphorelay activity in vivo that can distinguish between basal and cytokinin dependent effects of overexpressed TCS members. The TCS phosphorelay can be positively activated by cytokinin and inhibited by pharmaceuticals or naturally interfering components. In this case we took advantage of the phosphohistidine-phosphatase Arabidopsis Response Regulator (ARR) 22 and investigated its phosphocompetition with other TCS members in regulating promoters of ARR5 and WUS in Arabidopsis thaliana cell culture protoplasts. In congruency with the proposed function of ARR22, overexpression of ARR22 blocked the activation of all B-type ARRs in this study in a TCS dependent manner. Furthermore, this effect could not be mimicked by A-type response regulator overexpression or compensated by AHP overexpression. Compared to other reporter assays, ours mimicked effects previously observed only in transgenic plants for all of the TCS proteins studied, suggesting that it is possible to expose phosphocompetition. Thus, our approach can be used to investigate gene signaling networks involving the TCS by leveraging ARR22 as a TCS inhibitor along with B-type ARR overexpression.
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Affiliation(s)
- Niklas Wallmeroth
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Daniel Jeschke
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Daniel Slane
- Max-Planck Institute for Developmental Biology, Tübingen, Germany
| | - Janine Nägele
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Manikandan Veerabagu
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Virtudes Mira-Rodado
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Kenneth Wayne Berendzen
- Department of Plant Physiology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
- Department of the Central Facilities at Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
- * E-mail:
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Yin J, Guan X, Zhang H, Wang L, Li H, Zhang Q, Chen T, Xu Z, Hong Z, Cao Y, Zhang Z. An MAP kinase interacts with LHK1 and regulates nodule organogenesis in Lotus japonicus. SCIENCE CHINA-LIFE SCIENCES 2019; 62:1203-1217. [DOI: 10.1007/s11427-018-9444-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 12/07/2018] [Indexed: 10/27/2022]
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Potter KC, Wang J, Schaller GE, Kieber JJ. Cytokinin modulates context-dependent chromatin accessibility through the type-B response regulators. NATURE PLANTS 2018; 4:1102-1111. [PMID: 30420712 DOI: 10.1038/s41477-018-0290-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 09/26/2018] [Indexed: 05/18/2023]
Abstract
The phytohormone cytokinin regulates diverse aspects of plant growth and development, probably through context-dependent transcriptional regulation that relies on a dynamic interplay between regulatory proteins and chromatin. We employed the assay for transposase accessible chromatin with sequencing to profile changes in the chromatin landscape of Arabidopsis roots and shoots in response to cytokinin. Our results reveal differentially accessible chromatin regions indicative of dynamic regulation in response to cytokinin. These changes in chromatin occur preferentially upstream of cytokinin-regulated genes. The changes also largely overlap with binding sites for the type-B ARABIDOPSIS RESPONSE REGULATORS (ARRs), transcription factors that mediate the primary response to cytokinin. Furthermore, the type-B ARRs were found to be necessary for the changes in chromatin state in response to cytokinin. Last, we identified context-dependent responses by comparing root and shoot profiles. This study provides new insight into the dynamics between cytokinin and chromatin with regard to directing transcriptional programmes and how cytokinin mediates its pleiotropic effects.
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Affiliation(s)
- Kevin C Potter
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - Judy Wang
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - G Eric Schaller
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - Joseph J Kieber
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA.
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Skalický V, Kubeš M, Napier R, Novák O. Auxins and Cytokinins-The Role of Subcellular Organization on Homeostasis. Int J Mol Sci 2018; 19:E3115. [PMID: 30314316 PMCID: PMC6213326 DOI: 10.3390/ijms19103115] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/05/2018] [Accepted: 10/09/2018] [Indexed: 12/18/2022] Open
Abstract
Plant hormones are master regulators of plant growth and development. Better knowledge of their spatial signaling and homeostasis (transport and metabolism) on the lowest structural levels (cellular and subcellular) is therefore crucial to a better understanding of developmental processes in plants. Recent progress in phytohormone analysis at the cellular and subcellular levels has greatly improved the effectiveness of isolation protocols and the sensitivity of analytical methods. This review is mainly focused on homeostasis of two plant hormone groups, auxins and cytokinins. It will summarize and discuss their tissue- and cell-type specific distributions at the cellular and subcellular levels.
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Affiliation(s)
- Vladimír Skalický
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany of the Czech Academy of Sciences & Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
| | - Martin Kubeš
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
| | - Richard Napier
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany of the Czech Academy of Sciences & Faculty of Science of Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic.
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Shanks CM, Hecker A, Cheng CY, Brand L, Collani S, Schmid M, Schaller GE, Wanke D, Harter K, Kieber JJ. Role of BASIC PENTACYSTEINE transcription factors in a subset of cytokinin signaling responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:458-473. [PMID: 29763523 DOI: 10.1111/tpj.13962] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 04/26/2018] [Accepted: 04/30/2018] [Indexed: 06/08/2023]
Abstract
Cytokinin plays diverse roles in plant growth and development, generally acting by modulating gene transcription in target tissues. The type-B Arabidopsis response regulators (ARR) transcription factors have emerged as primary targets of cytokinin signaling and are required for essentially all cytokinin-mediated changes in gene expression. The diversity of cytokinin function is likely imparted by the activity of various transcription factors working with the type-B ARRs to alter specific sets of target genes. One potential set of co-regulators modulating the cytokinin response are the BARLEY B-RECOMBINANT/BASIC PENTACYSTEINE (BBR/BPC) family of plant-specific transcription factors. Here, we show that disruption of multiple BPCs results in reduced sensitivity to cytokinin. Further, the BPCs are necessary for the induction of a subset of genes in response to cytokinin. We identified direct in vivo targets of BPC6 using ChIP-Seq and found an enrichment of promoters of genes differentially expressed in response to cytokinin. Further, a significant number of BPC6 regulated genes are also direct targets of the type-B ARRs. Potential cis-binding elements for a number of other transcription factors linked to cytokinin action are enriched in the BPC binding fragments, including those for the cytokinin response factors (CRFs). In addition, several BPCs interact with a subset of type-A ARRs. Consistent with these results, a significant number of genes whose expression is altered in bpc mutant roots are also mis-expressed in crf1,3,5,6 and type-A arr3,4,5,6,7,8,9,15 mutant roots. These results suggest that the BPCs are part of a complex network of transcription factors that are involved in the response to cytokinin.
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Affiliation(s)
- Carly M Shanks
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Andreas Hecker
- Center for Plant Molecular Biology, Plant Physiology, University of Tübingen, 72076, Tübingen, Germany
| | - Chia-Yi Cheng
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Luise Brand
- Center for Plant Molecular Biology, Plant Physiology, University of Tübingen, 72076, Tübingen, Germany
- Department of Plant Developmental Biology, Max Planck Institute for Plant Breeding Research, 50829, Köln, Germany
| | - Silvio Collani
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-901 87, Umeå, Sweden
- Max Planck Institute for Developmental Biology, 72076, Tübingen, Germany
| | - Markus Schmid
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-901 87, Umeå, Sweden
| | - G Eric Schaller
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755 (603) 646-1347, USA
| | - Dierk Wanke
- Center for Plant Molecular Biology, Plant Physiology, University of Tübingen, 72076, Tübingen, Germany
- Saarland University, Molecular Plant Biology, Campus A2.4, 66123, Saarbrücken, Germany
| | - Klaus Harter
- Center for Plant Molecular Biology, Plant Physiology, University of Tübingen, 72076, Tübingen, Germany
| | - Joseph J Kieber
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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Kaltenegger E, Leng S, Heyl A. The effects of repeated whole genome duplication events on the evolution of cytokinin signaling pathway. BMC Evol Biol 2018; 18:76. [PMID: 29843594 PMCID: PMC5975490 DOI: 10.1186/s12862-018-1153-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 03/14/2018] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND It is thought that after whole-genome duplications (WGDs), a large fraction of the duplicated gene copies is lost over time while few duplicates are retained. Which factors promote survival or death of a duplicate remains unclear and the underlying mechanisms are poorly understood. According to the model of gene dosage balance, genes encoding interacting proteins are predicted to be preferentially co-retained after WGDs. Among these are genes encoding proteins involved in complexes or in signal transduction. RESULTS We have investigated the way that repeated WGDs during land plant evolution have affected cytokinin signaling to study patterns of gene duplicability and co-retention in this important signal transduction pathway. Through the integration of phylogenetic analyses with comparisons of genome collinearity, we have found that signal input mediated by cytokinin receptors proved to be highly conserved over long evolutionary time-scales, with receptors showing predominantly gene loss after repeated WGDs. However, the downstream elements, e,g. response regulators, were mainly retained after WGDs and thereby formed gene families in most plant lineages. CONCLUSIONS Gene dosage balance between the interacting components indicated by co-retention after WGDs seems to play a minor role in the evolution of cytokinin signaling pathway. Overall, core genes of cytokinin signaling show a highly heterogeneous pattern of gene retention after WGD, reflecting complex relationships between the various factors that shape the long-term fate of a duplicated gene.
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Affiliation(s)
- Elisabeth Kaltenegger
- Department Biochemical Ecology and Molecular Evolution, Botanical Institute, Christian-Albrechts-University, Kiel, Germany
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
| | - Svetlana Leng
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
| | - Alexander Heyl
- Institute of Applied Genetics, Freie Universität Berlin, Berlin, Germany
- Biology Department, Adelphi University, Garden City, USA
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Lomin SN, Myakushina YA, Arkhipov DV, Leonova OG, Popenko VI, Schmülling T, Romanov GA. Studies of cytokinin receptor-phosphotransmitter interaction provide evidences for the initiation of cytokinin signalling in the endoplasmic reticulum. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:192-202. [PMID: 32291033 DOI: 10.1071/fp16292] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Accepted: 01/11/2017] [Indexed: 05/06/2023]
Abstract
Cytokinin receptors were shown recently to be localised mainly to the endoplasmic reticulum (ER); however, the activity of ER-located receptors was not proven. We have therefore tested the functionality of ER-located Arabidopsis receptors. The first step of cytokinin signal transduction is the transfer of a phosphoryl group from the activated receptor to a phosphotransfer protein. To determine the subcellular localisation of receptor-phosphotransmitter interaction in planta, BiFC experiments were performed. Receptors ARABIDOPSIS HISTIDINE KINASE 2 (AHK2), AHK3 and AHK4 (CRE1) and phosphotransmitters ARABIDOPSIS HISTIDINE-CONTAINING PHOSPHOTRANSMITTER 1 (AHP1), AHP2 and AHP3 fused to split-eYFP were transiently expressed in Nicotiana benthamiana leaves. Receptor-phosphotransmitter pairs were shown to interact in every possible combination in a pattern reflecting the ER. Receptor dimers, an active form of the receptors, were also detected in the ER. According to BiFC and protease protection data, the catalytic part of AHK3 was located in the cytoplasm whereas the hormone binding module faced the ER lumen. This topology is consistent with receptor signalling from the ER membrane. Finally, the functionality of receptors in different membrane fractions was tested using an in vitro kinase assay visualising the phosphorylation of phosphotransfer proteins. The detected cytokinin-dependent phosphotransfer activity was confined mainly to the ER-enriched fraction. Collectively, our data demonstrate that ER-located cytokinin receptors are active in cytokinin signal transduction. Hence, intracellular cytokinins appear to play an essential role in cytokinin signalling. An updated model for the spatial organisation of cytokinin transport form activation, intracellular trafficking and signalling from the ER is proposed.
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Affiliation(s)
- Sergey N Lomin
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya str. 35, 127276 Moscow, Russia
| | - Yulia A Myakushina
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya str. 35, 127276 Moscow, Russia
| | - Dmitry V Arkhipov
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya str. 35, 127276 Moscow, Russia
| | - Olga G Leonova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov str. 32, 119991 Moscow, Russia
| | - Vladimir I Popenko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov str. 32, 119991 Moscow, Russia
| | - Thomas Schmülling
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany
| | - Georgy A Romanov
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya str. 35, 127276 Moscow, Russia
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Hodgens C, Nimchuk ZL, Kieber JJ. indCAPS: A tool for designing screening primers for CRISPR/Cas9 mutagenesis events. PLoS One 2017; 12:e0188406. [PMID: 29141013 PMCID: PMC5687723 DOI: 10.1371/journal.pone.0188406] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/06/2017] [Indexed: 11/25/2022] Open
Abstract
Genetic manipulation of organisms using CRISPR/Cas9 technology generally produces small insertions/deletions (indels) that can be difficult to detect. Here, we describe a technique to easily and rapidly identify such indels. Sequence-identified mutations that alter a restriction enzyme recognition site can be readily distinguished from wild-type alleles using a cleaved amplified polymorphic sequence (CAPS) technique. If a restriction site is created or altered by the mutation such that only one allele contains the restriction site, a polymerase chain reaction (PCR) followed by a restriction digest can be used to distinguish the two alleles. However, in the case of most CRISPR-induced alleles, no such restriction sites are present in the target sequences. In this case, a derived CAPS (dCAPS) approach can be used in which mismatches are purposefully introduced in the oligonucleotide primers to create a restriction site in one, but not both, of the amplified templates. Web-based tools exist to aid dCAPS primer design, but when supplied sequences that include indels, the current tools often fail to suggest appropriate primers. Here, we report the development of a Python-based, species-agnostic web tool, called indCAPS, suitable for the design of PCR primers used in dCAPS assays that is compatible with indels. This tool should have wide utility for screening editing events following CRISPR/Cas9 mutagenesis as well as for identifying specific editing events in a pool of CRISPR-mediated mutagenesis events. This tool was field-tested in a CRISPR mutagenesis experiment targeting a cytokinin receptor (AHK3) in Arabidopsis thaliana. The tool suggested primers that successfully distinguished between wild-type and edited alleles of a target locus and facilitated the isolation of two novel ahk3 null alleles. Users can access indCAPS and design PCR primers to employ dCAPS to identify CRISPR/Cas9 alleles at http://indcaps.kieber.cloudapps.unc.edu/.
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Affiliation(s)
- Charles Hodgens
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Zachary L. Nimchuk
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Joseph J. Kieber
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Kushwah S, Laxmi A. The interaction between glucose and cytokinin signaling in controlling Arabidopsis thaliana seedling root growth and development. PLANT SIGNALING & BEHAVIOR 2017; 12:e1312241. [PMID: 28467152 PMCID: PMC5501229 DOI: 10.1080/15592324.2017.1312241] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Cytokinin (CK) and glucose (GLC) control several common responses in plants. There is an extensive overlap between CK and GLC signal transduction pathways in Arabidopsis. Physiologically, both GLC and CK could regulate root length in light. CK interacts with GLC via HXK1 dependent pathway for root length control. Wild-type (WT) roots cannot elongate in the GLC free medium while CK-receptor mutant ARABIDOPSIS HISTIDINE KINASE4 (ahk4) and type B ARR triple mutant ARABIDOPSIS RESPONSE REGULATOR1, 10,11 (arr1, 10,11) roots could elongate even in the absence of GLC as compared with the WT. The root hair initiation was also found defective in CK signaling mutants ahk4, arr1,10,11 and arr3,4,5,6,8,9 on increasing GLC concentration (up to 3%); and lesser number of root hairs were visible even at 5% GLC as compared with the WT. Out of 941 BAP regulated genes, 103 (11%) genes were involved in root growth and development. Out of these 103 genes, 60 (58%) genes were also regulated by GLC. GLC could regulate 5736 genes, which include 327 (6%) genes involved in root growth and development. Out of these 327 genes, 60 (18%) genes were also regulated by BAP. Both GLC and CK signaling cannot alter root length in light in auxin signaling mutant AUXIN RESPONSE3/INDOLE-3-ACETIC ACID17 (axr3/iaa17) suggesting that they may involve auxin signaling component as a nodal point. Therefore CK- and GLC- signaling are involved in controlling different aspects of root growth and development such as root length, with auxin signaling components working as downstream target.
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Affiliation(s)
- Sunita Kushwah
- National Institute of Plant Genome Research, New Delhi, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, New Delhi, India
- CONTACT Ashverya Laxmi National Institute of Plant Genome Research, Aruna Asaf Ali Road, New Delhi-110067, India
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Albrecht T, Argueso CT. Should I fight or should I grow now? The role of cytokinins in plant growth and immunity and in the growth-defence trade-off. ANNALS OF BOTANY 2017; 119:725-735. [PMID: 27864225 PMCID: PMC5379597 DOI: 10.1093/aob/mcw211] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 06/28/2016] [Accepted: 08/31/2016] [Indexed: 05/05/2023]
Abstract
BACKGROUND Perception and activation of plant immunity require a remarkable level of signalling plasticity and control. In Arabidopsis and other plant species, constitutive defence activation leads to resistance to a broad spectrum of biotrophic pathogens, but also frequently to stunted growth and reduced seed set. Plant hormones are important integrators of the physiological responses that influence the outcome of plant-pathogen interactions. SCOPE We review the mechanisms by which the plant hormone cytokinin regulates both plant growth and response to pathogens, and how cytokinins may connect these two processes, ultimately affecting the growth trade-offs observed in plant immunity.
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Affiliation(s)
| | - Cristiana T. Argueso
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO 80523, USA
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Ding W, Tong H, Zheng W, Ye J, Pan Z, Zhang B, Zhu S. Isolation, Characterization and Transcriptome Analysis of a Cytokinin Receptor Mutant Osckt1 in Rice. FRONTIERS IN PLANT SCIENCE 2017; 8:88. [PMID: 28197164 PMCID: PMC5281565 DOI: 10.3389/fpls.2017.00088] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 01/16/2017] [Indexed: 05/04/2023]
Abstract
Cytokinins play important roles in regulating plant development, including shoot and root meristems, leaf longevity, and grain yield. However, the in planta functions of rice cytokinin receptors have not been genetically characterized yet. Here we isolated a rice mutant, Osckt1, with enhanced tolerance to cytokinin treatment. Further analysis showed that Osckt1 was insensitive to aromatic cytokinins but responded normally to isoprenoid and phenylurea-type cytokinins. Map-based cloning revealed that the mutation occurred in a putative cytokinin receptor gene, histidine kinase 6 (OsHK6). OsCKT1 was found to be expressed in various tissues throughout the plant and the protein was located in the endoplasmic reticulum. In addition, whole-genome gene expression profiling analysis showed that OsCKT1 was involved in cytokinin regulation of a number of biological processes, including secondary metabolism, sucrose and starch metabolism, chlorophyll synthesis, and photosynthesis. Our results demonstrate that OsCKT1 plays important roles in cytokinin perception and control of root development in rice.
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Affiliation(s)
- Wona Ding
- College of Science and Technology, Ningbo UniversityNingbo, China
| | - Huishan Tong
- School of Marine Sciences, Ningbo UniversityNingbo, China
| | - Wenjuan Zheng
- College of Science and Technology, Ningbo UniversityNingbo, China
| | - Jing Ye
- College of Science and Technology, Ningbo UniversityNingbo, China
| | - Zhichong Pan
- College of Science and Technology, Ningbo UniversityNingbo, China
| | - Botao Zhang
- Cixi Institute of Biomedical Engineering, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of SciencesNingbo, China
- *Correspondence: Botao Zhang, Shihua Zhu,
| | - Shihua Zhu
- College of Science and Technology, Ningbo UniversityNingbo, China
- *Correspondence: Botao Zhang, Shihua Zhu,
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Raines T, Blakley IC, Tsai YC, Worthen JM, Franco-Zorrilla JM, Solano R, Schaller GE, Loraine AE, Kieber JJ. Characterization of the cytokinin-responsive transcriptome in rice. BMC PLANT BIOLOGY 2016; 16:260. [PMID: 27931185 PMCID: PMC5146874 DOI: 10.1186/s12870-016-0932-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 10/25/2016] [Indexed: 05/18/2023]
Abstract
BACKGROUND Cytokinin activates transcriptional cascades important for development and the responses to biotic and abiotic stresses. Most of what is known regarding cytokinin-regulated gene expression comes from studies of the dicotyledonous plant Arabidopsis thaliana. To expand the understanding of the cytokinin-regulated transcriptome, we employed RNA-Seq to analyze gene expression in response to cytokinin in roots and shoots of the monocotyledonous plant rice. RESULTS We identified over 4,600 and approximately 2,400 genes differentially expressed in response to cytokinin in roots and shoots respectively. There were some similarities in the sets of cytokinin-regulated genes identified in rice and Arabidopsis, including an up-regulation of genes that act to reduce cytokinin function. Consistent with this, we found that the preferred DNA-binding motif of a rice type-B response regulator is similar to those from Arabidopsis. Analysis of the genes regulated by cytokinin in rice revealed a large number of transcription factors, receptor-like kinases, and genes involved in protein degradation, as well as genes involved in development and the response to biotic stress. Consistent with the over-representation of genes involved in biotic stress, there is a substantial overlap in the genes regulated by cytokinin and those differentially expressed in response to pathogen infection, suggesting that cytokinin plays an integral role in the transcriptional response to pathogens in rice, including the induction of a large number of WRKY transcription factors. CONCLUSIONS These results begin to unravel the complex gene regulation after cytokinin perception in a crop of agricultural importance and provide insight into the processes and responses modulated by cytokinin in monocots.
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Affiliation(s)
- Tracy Raines
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280 USA
- Present address: AgBiome, Inc., 104 TW Alexander Drive, Bldg 18, Research Triangle Park, NC 27713 USA
| | - Ivory C. Blakley
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, North Carolina Research Campus, Kannapolis, NC 28081 USA
| | - Yu-Chang Tsai
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280 USA
- Present address: Department of Agronomy, National Taiwan University, Taipei, 10617 Taiwan
| | | | - José Manuel Franco-Zorrilla
- Genomics Unit, Centro Nacional de Biotecnología (CNB)-Consejo Superior de Investigaciones Científicas (CSIC), Darwin 3, 28049 Madrid, Spain
| | - Roberto Solano
- Department of Plant Molecular Genetics, Centro Nacional de Biotecnología (CNB)-Consejo Superior de Investigaciones Científicas (CSIC), Darwin 3, 28049 Madrid, Spain
| | - G. Eric Schaller
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755 USA
| | - Ann E. Loraine
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, North Carolina Research Campus, Kannapolis, NC 28081 USA
| | - Joseph J. Kieber
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599-3280 USA
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Alvarez AF, Barba-Ostria C, Silva-Jiménez H, Georgellis D. Organization and mode of action of two component system signaling circuits from the various kingdoms of life. Environ Microbiol 2016; 18:3210-3226. [DOI: 10.1111/1462-2920.13397] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 05/17/2016] [Accepted: 05/23/2016] [Indexed: 11/26/2022]
Affiliation(s)
- Adrian F. Alvarez
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México; 04510 México City, México
| | - Carlos Barba-Ostria
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México; 04510 México City, México
| | - Hortencia Silva-Jiménez
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México; 04510 México City, México
| | - Dimitris Georgellis
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México; 04510 México City, México
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27
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Zürcher E, Müller B. Cytokinin Synthesis, Signaling, and Function--Advances and New Insights. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 324:1-38. [PMID: 27017005 DOI: 10.1016/bs.ircmb.2016.01.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The plant hormones referred to as cytokinins are chemical signals that control numerous developmental processes throughout the plant life cycle, including gametogenesis, root meristem specification, vascular development, shoot and root growth, meristem homeostasis, senescence, and more. In addition, they mediate responses to environmental cues such as light, stress, and nutrient conditions. The core mechanistics of cytokinin metabolism and signaling have been elucidated, but more layers of regulation, additional functions, and interactions with other signals are continuously discovered and described. In this chapter, we recapitulate the highlights of over 100 years of cytokinin research covering its isolation, the elucidation of phosphorelay signaling, and how cytokinin functions in various developmental contexts including its interaction with other pathways. Additionally, given cytokinin's paracrine signaling mechanism, we postulate that cellular exporters for cytokinins exist.
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Affiliation(s)
- E Zürcher
- Department of Plant and Microbial Biology, Zurich-Basel Plant Science Center, University of Zurich Zurich, Switzerland
| | - B Müller
- Department of Plant and Microbial Biology, Zurich-Basel Plant Science Center, University of Zurich Zurich, Switzerland.
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28
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Li G, Ma J, Tan M, Mao J, An N, Sha G, Zhang D, Zhao C, Han M. Transcriptome analysis reveals the effects of sugar metabolism and auxin and cytokinin signaling pathways on root growth and development of grafted apple. BMC Genomics 2016; 17:150. [PMID: 26923909 PMCID: PMC4770530 DOI: 10.1186/s12864-016-2484-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 02/17/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The root architecture of grafted apple (Malus spp.) is affected by various characteristics of the scions. To provide information on the molecular mechanisms underlying this influence, we examined root transcriptomes of M. robusta rootstock grafted with scions of wild-type (WT) apple (M. spectabilis) and a more-branching (MB) mutant at the branching stage. RESULTS The growth rate of rootstock grafted MB was repressed significantly, especially the primary root length and diameter, and root weight. Biological function categories of differentially expressed genes were significantly enriched in processes associated with hormone signal transduction and intracellular activity, with processes related to the cell cycle especially down-regulated. Roots of rootstock grafted with MB scions displayed elevated auxin and cytokinin contents and reduced expression of MrPIN1, MrARF, MrAHP, most MrCRE1 genes, and cell growth-related genes MrGH3, MrSAUR and MrTCH4. Although auxin accumulation and transcription of MrPIN3, MrALF1 and MrALF4 tended to induce lateral root formation in MB-grafted rootstock, the number of lateral roots was not significantly changed. Sucrose, fructose and glucose contents were not decreased in MB-grafted roots compared with those bearing WT scions, but glycolysis and tricarboxylic acid cycle metabolic activities were repressed. Root resistance and nitrogen metabolism were reduced in MB-grafted roots as well. CONCLUSIONS Our findings suggest that root growth and development of rootstock are mainly influenced by sugar metabolism and auxin and cytokinin signaling pathways. This study provides a basis that the characteristics of scions are related to root growth and development, resistance and activity of rootstocks.
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Affiliation(s)
- Guofang Li
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Juanjuan Ma
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Ming Tan
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Jiangping Mao
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Na An
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Guangli Sha
- Institute of agricultural science, Qingdao, Shandong, 266000, China.
| | - Dong Zhang
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Caiping Zhao
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| | - Mingyu Han
- College of Horticulture, Northwest A & F University, Yangling, Shaanxi, 712100, China.
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29
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von Schwartzenberg K, Lindner AC, Gruhn N, Šimura J, Novák O, Strnad M, Gonneau M, Nogué F, Heyl A. CHASE domain-containing receptors play an essential role in the cytokinin response of the moss Physcomitrella patens. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:667-79. [PMID: 26596764 PMCID: PMC4737067 DOI: 10.1093/jxb/erv479] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
While the molecular basis for cytokinin action is quite well understood in flowering plants, little is known about the cytokinin signal transduction in early diverging land plants. The genome of the bryophyte Physcomitrella patens (Hedw.) B.S. encodes three classical cytokinin receptors, the CHASE domain-containing histidine kinases, CHK1, CHK2, and CHK3. In a complementation assay with protoplasts of receptor-deficient Arabidopsis thaliana as well as in cytokinin binding assays, we found evidence that CHK1 and CHK2 receptors can function in cytokinin perception. Using gene targeting, we generated a collection of CHK knockout mutants comprising single (Δchk1, Δchk2, Δchk3), double (Δchk1,2, Δchk1,3, Δchk2,3), and triple (Δchk1,2,3) mutants. Mutants were characterized for their cytokinin response and differentiation capacities. While the wild type did not grow on high doses of cytokinin (1 µM benzyladenine), the Δchk1,2,3 mutant exhibited normal protonema growth. Bud induction assays showed that all three cytokinin receptors contribute to the triggering of budding, albeit to different extents. Furthermore, while the triple mutant showed no response in this bioassay, the remaining mutants displayed budding responses in a diverse manner to different types and concentrations of cytokinins. Determination of cytokinin levels in mutants showed no drastic changes for any of the cytokinins; thus, in contrast to Arabidopsis, revealing only small impacts of cytokinin signaling on homeostasis. In summary, our study provides a first insight into the molecular action of cytokinin in an early diverging land plant and demonstrates that CHK receptors play an essential role in bud induction and gametophore development.
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Affiliation(s)
| | - Ann-Cathrin Lindner
- Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststr. 18, D-22609 Hamburg, Germany
| | - Njuscha Gruhn
- Institute for Biology/ Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany
| | - Jan Šimura
- Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators & Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic
| | - Martine Gonneau
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRA Centre de Versailles-Grignon, Route de St-Cyr, 78026 Versailles Cedex, France
| | - Fabien Nogué
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRA Centre de Versailles-Grignon, Route de St-Cyr, 78026 Versailles Cedex, France
| | - Alexander Heyl
- Institute for Biology/ Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany Biology Department, Adelphi University, Science 116, 1 South Avenue, PO Box 701, Garden City, NY 11530-070, USA
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30
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Pekárová B, Szmitkowska A, Dopitová R, Degtjarik O, Žídek L, Hejátko J. Structural Aspects of Multistep Phosphorelay-Mediated Signaling in Plants. MOLECULAR PLANT 2016; 9:71-85. [PMID: 26633861 DOI: 10.1016/j.molp.2015.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 05/16/2023]
Abstract
The multistep phosphorelay (MSP) is a central signaling pathway in plants integrating a wide spectrum of hormonal and environmental inputs and controlling numerous developmental adaptations. For the thorough comprehension of the molecular mechanisms underlying the MSP-mediated signal recognition and transduction, the detailed structural characterization of individual members of the pathway is critical. In this review we describe and discuss the recently known crystal and nuclear magnetic resonance structures of proteins acting in MSP signaling in higher plants, focusing particularly on cytokinin and ethylene signaling in Arabidopsis thaliana. We discuss the range of functional aspects of available structural information including determination of ligand specificity, activation of the receptor via its autophosphorylation, and downstream signal transduction through the phosphorelay. We compare the plant structures with their bacterial counterparts and show that although the overall similarity is high, the differences in structural details are frequent and functionally important. Finally, we discuss emerging knowledge on molecular recognition mechanisms in the MSP, and mention the latest findings regarding structural determinants of signaling specificity in the Arabidopsis MSP that could serve as a general model of this pathway in all higher plants.
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Affiliation(s)
- Blanka Pekárová
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Agnieszka Szmitkowska
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Radka Dopitová
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Oksana Degtjarik
- Faculty of Science, Institute of Chemistry and Biochemistry, University of South Bohemia, 370 05 České Budějovice, Czech Republic
| | - Lukáš Žídek
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jan Hejátko
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
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31
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Raines T, Shanks C, Cheng CY, McPherson D, Argueso CT, Kim HJ, Franco-Zorrilla JM, López-Vidriero I, Solano R, Vaňková R, Schaller GE, Kieber JJ. The cytokinin response factors modulate root and shoot growth and promote leaf senescence in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 85:134-47. [PMID: 26662515 DOI: 10.1111/tpj.13097] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/13/2015] [Accepted: 11/24/2015] [Indexed: 05/23/2023]
Abstract
The cytokinin response factors (CRFs) are a group of related AP2/ERF transcription factors that are transcriptionally induced by cytokinin. Here we explore the role of the CRFs in Arabidopsis thaliana growth and development by analyzing lines with decreased and increased CRF function. While single crf mutations have no appreciable phenotypes, disruption of multiple CRFs results in larger rosettes, delayed leaf senescence, a smaller root apical meristem (RAM), reduced primary and lateral root growth, and, in etiolated seedlings, shorter hypocotyls. In contrast, overexpression of CRFs generally results in the opposite phenotypes. The crf1,2,5,6 quadruple mutant is embryo lethal, indicating that CRF function is essential for embryo development. Disruption of the CRFs results in partially insensitivity to cytokinin in a root elongation assay and affects the basal expression of a significant number of cytokinin-regulated genes, including the type-A ARRs, although it does not impair the cytokinin induction of the type-A ARRs. Genes encoding homeobox transcription factors are mis-expressed in the crf1,3,5,6 mutant, including STIMPY/WOX9 that is required for root and shoot apical meristem maintenance roots and which has previously been linked to cytokinin. These results indicate that the CRF transcription factors play important roles in multiple aspects of plant growth and development, in part through a complex interaction with cytokinin signaling.
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Affiliation(s)
- Tracy Raines
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Carly Shanks
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Chia-Yi Cheng
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Duncan McPherson
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Cristiana T Argueso
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Hyo J Kim
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
| | - José M Franco-Zorrilla
- Unidad de Genómica and Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas, Campus Universidad Autónoma, 28049, Madrid, Spain
| | - Irene López-Vidriero
- Unidad de Genómica and Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas, Campus Universidad Autónoma, 28049, Madrid, Spain
| | - Roberto Solano
- Unidad de Genómica and Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas, Campus Universidad Autónoma, 28049, Madrid, Spain
| | - Radomíra Vaňková
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany AS CR, Rozvojová 263, 165 02, Prague, Czech Republic
| | - G Eric Schaller
- Department of Biological Sciences, Dartmouth College, Hanover, NH, 03755, USA
| | - Joseph J Kieber
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
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32
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Chauhan N. Two-component phosphorelays in fungal mitochondria and beyond. Mitochondrion 2015; 22:60-5. [PMID: 25858273 DOI: 10.1016/j.mito.2015.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 11/19/2022]
Abstract
Prokaryotes, eukaryotic microorganisms and plants utilize two-component signal transduction pathways to detect and respond to various environmental cues. These signaling cascades were acquired by eukaryotes via horizontal gene transfer events from ancestral bacteria. Recent exciting discoveries have identified two-component signaling systems in mitochondria and chloroplasts of several eukaryotic microorganisms and plants, therefore providing important clues to the evolutionary transition of these signaling cascades from prokaryotes to eukaryotes. This review will focus on the role of two-component signal transduction pathways in fungal pathogenesis and also discuss key new discoveries of presence of proteins participating in these signaling pathways in mitochondrion. Before addressing these issues, I first briefly describe the magnitude and the economic impact of the healthcare problems caused by fungal pathogens.
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Affiliation(s)
- Neeraj Chauhan
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, 225 Warren Street, Newark, NJ 07103, United States; Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers, The State University of New Jersey, 225 Warren Street, Newark, NJ 07103, United States.
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33
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Marchadier E, Hetherington AM. Involvement of two-component signalling systems in the regulation of stomatal aperture by light in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2014; 203:462-468. [PMID: 24758561 DOI: 10.1111/nph.12813] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 03/14/2014] [Indexed: 05/07/2023]
Abstract
Two-component signalling (TCS) systems play important roles in cytokinin and ethylene signalling in Arabidopsis thaliana. Although the involvement of histidine kinases (AHKs) in drought stress responses has been described, their role and that of histidine phosphotransferases (AHPs) in guard cell signalling remain to be fully elucidated. Here, we investigated the roles of TCS genes, the histidine phosphotransferase AHP2 and the histidine kinases AHK2 and AHK3, previously reported to play roles in cytokinin and abscisic acid (ABA) signalling. We show that AHP2 is present in the nucleus and the cytoplasm, and is involved in light-induced opening. We also present evidence that there is some redistribution of AHP2 from the nucleus to the cytoplasm on addition of ABA. In addition, we provide data to support a role for the cytokinin receptors AHK2 and AHK3 in light-induced stomatal opening and, by inference, in controlling the stomatal sensitivity to ABA. Our results provide new insights into the operation of TCS in plants, cross-talk in stomatal signalling and, in particular, the process of light-induced stomatal opening.
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Affiliation(s)
- Elodie Marchadier
- Department of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK
- INRA-Institut National de la Recherche Agronomique, UMR 1318, Institut Jean-Pierre Bourgin, RD10, F-78000, Versailles, France
| | - Alistair M Hetherington
- Department of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK
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34
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Sun L, Zhang Q, Wu J, Zhang L, Jiao X, Zhang S, Zhang Z, Sun D, Lu T, Sun Y. Two rice authentic histidine phosphotransfer proteins, OsAHP1 and OsAHP2, mediate cytokinin signaling and stress responses in rice. PLANT PHYSIOLOGY 2014; 165:335-45. [PMID: 24578505 PMCID: PMC4012592 DOI: 10.1104/pp.113.232629] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cytokinin plays an important role in plant development and stress tolerance. Studies of Arabidopsis (Arabidopsis thaliana) have demonstrated that cytokinin acts through a two-component system that includes a histidine (His) kinase, a His phosphotransfer protein (HP), and a response regulator. Phylogenetic analyses have revealed the conservation of His kinases but lineage-specific expansion of HPs and response regulators in rice (Oryza sativa). However, whether the functions of rice HPs have diverged remains unknown. In this study, two rice authentic HPs (OsAHP1 and OsAHP2) were knocked down simultaneously via RNA interference (RNAi), and the transgenic OsAHP-RNAi plants exhibited phenotypes expected for a deficiency in cytokinin signaling, including dwarfism with reduced internode lengths, enhanced lateral root growth, early leaf senescence, and reduced tiller numbers and fertility under natural conditions. The OsAHP-RNAi seedlings were also hyposensitive to exogenous cytokinin. Furthermore, OsAHP-RNAi seedlings were hypersensitive to salt treatment but resistant to osmotic stress relative to wild-type plants. These results indicate that OsAHPs function as positive regulators of the cytokinin signaling pathway and play different roles in salt and drought tolerance in rice.
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35
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Gruhn N, Halawa M, Snel B, Seidl MF, Heyl A. A subfamily of putative cytokinin receptors is revealed by an analysis of the evolution of the two-component signaling system of plants. PLANT PHYSIOLOGY 2014; 165:227-37. [PMID: 24520157 PMCID: PMC4012582 DOI: 10.1104/pp.113.228080] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 02/07/2014] [Indexed: 05/05/2023]
Abstract
The two-component signaling system--the major signaling pathway of bacteria--is found among higher eukaryotes only in plants, where it regulates diverse processes, such as the signaling of the phytohormone cytokinin. Cytokinin is perceived by a hybrid histidine (His) kinase receptor, and the signal is transduced by a multistep phosphorelay system of His phosphotransfer proteins and different classes of response regulators (RRs). To shed light on the origin and evolution of the two-component signaling system members in plants, we conducted a comprehensive domain-based phylogenetic study across the relevant kingdoms, including Charophyceae algae, the group of green algae giving rise to land plants. Surprisingly, we identified a subfamily of cytokinin receptors with members only from the early diverging land plants Marchantia polymorpha and Physcomitrella patens and then experimentally characterized two members of this subfamily. His phosphotransfer proteins of Charophyceae seemed to be more closely related to land plants than to other groups of green algae. Farther down the signaling pathway, the type-B RRs were found across all plant clades, but many members lack either the canonical Asp residue or the DNA binding domain. In contrast, the type-A RRs seemed to be limited to land plants. Finally, the analysis provided hints that one additional group of RRs, the type-C RRs, might be degenerated receptors and thus, of a different evolutionary origin than bona fide RRs.
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Affiliation(s)
- Nijuscha Gruhn
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität, 14195 Berlin, Germany (N.G., M.H., A.H.)
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, 3584 CH, Utrecht, The Netherlands (B.S., M.F.S.); and
- Centre for BioSystems Genomics, 6700 AB, Wageningen, The Netherlands (B.S., M.F.S.)
| | - Mhyeddeen Halawa
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität, 14195 Berlin, Germany (N.G., M.H., A.H.)
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, 3584 CH, Utrecht, The Netherlands (B.S., M.F.S.); and
- Centre for BioSystems Genomics, 6700 AB, Wageningen, The Netherlands (B.S., M.F.S.)
| | - Berend Snel
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität, 14195 Berlin, Germany (N.G., M.H., A.H.)
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, 3584 CH, Utrecht, The Netherlands (B.S., M.F.S.); and
- Centre for BioSystems Genomics, 6700 AB, Wageningen, The Netherlands (B.S., M.F.S.)
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Schuster C, Gaillochet C, Medzihradszky A, Busch W, Daum G, Krebs M, Kehle A, Lohmann JU. A regulatory framework for shoot stem cell control integrating metabolic, transcriptional, and phytohormone signals. Dev Cell 2014; 28:438-49. [PMID: 24576426 DOI: 10.1016/j.devcel.2014.01.013] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/25/2013] [Accepted: 01/13/2014] [Indexed: 11/24/2022]
Abstract
Plants continuously maintain pluripotent stem cells embedded in specialized tissues called meristems, which drive long-term growth and organogenesis. Stem cell fate in the shoot apical meristem (SAM) is controlled by the homeodomain transcription factor WUSCHEL (WUS) expressed in the niche adjacent to the stem cells. Here, we demonstrate that the bHLH transcription factor HECATE1 (HEC1) is a target of WUS and that it contributes to SAM function by promoting stem cell proliferation, while antagonizing niche cell activity. HEC1 represses the stem cell regulators WUS and CLAVATA3 (CLV3) and, like WUS, controls genes with functions in metabolism and hormone signaling. Among the targets shared by HEC1 and WUS are phytohormone response regulators, which we show to act as mobile signals in a universal feedback system. Thus, our work sheds light on the mechanisms guiding meristem function and suggests that the underlying regulatory system is far more complex than previously anticipated.
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Affiliation(s)
- Christoph Schuster
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Christophe Gaillochet
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Anna Medzihradszky
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Wolfgang Busch
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Gabor Daum
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Melanie Krebs
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Andreas Kehle
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Jan U Lohmann
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany.
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Two-component histidine phosphotransfer protein Ypd1 is not essential for viability in Candida albicans. EUKARYOTIC CELL 2014; 13:452-60. [PMID: 24489039 DOI: 10.1128/ec.00243-13] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Prokaryotes and lower eukaryotes, such as yeasts, utilize two-component signal transduction pathways to adapt cells to environmental stress and to regulate the expression of genes associated with virulence. One of the central proteins in this type of signaling mechanism is the phosphohistidine intermediate protein Ypd1. Ypd1 is reported to be essential for viability in the model yeast Saccharomyces cerevisiae. We present data here showing that this is not the case for Candida albicans. Disruption of YPD1 causes cells to flocculate and filament constitutively under conditions that favor growth in yeast form. To determine the function of Ypd1 in the Hog1 mitogen-activated protein kinase (MAPK) pathway, we measured phosphorylation of Hog1 MAPK in ypd1Δ/Δ and wild-type strains of C. albicans. Constitutive phosphorylation of Hog1 was observed in the ypd1Δ/Δ strain compared to the wild-type strain. Furthermore, fluorescence microscopy revealed that green fluorescent protein (GFP)-tagged Ypd1 is localized to both the nucleus and the cytoplasm. The subcellular segregation of GFP-tagged Ypd1 hints at an important role(s) of Ypd1 in regulation of Ssk1 (cytosolic) and Skn7 (nuclear) response regulator proteins via phosphorylation in C. albicans. Overall, our findings have profound implications for a mechanistic understanding of two-component signaling pathways in C. albicans, and perhaps in other pathogenic fungi.
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Abstract
Cytokinins are N (6) substituted adenine derivatives that affect many aspects of plant growth and development, including cell division, shoot initiation and growth, leaf senescence, apical dominance, sink/source relationships, nutrient uptake, phyllotaxis, and vascular, gametophyte, and embryonic development, as well as the response to biotic and abiotic factors. Molecular genetic studies in Arabidopsis have helped elucidate the mechanisms underlying the function of this phytohormone in plants. Here, we review our current understanding of cytokinin biosynthesis and signaling in Arabidopsis, the latter of which is similar to bacterial two-component phosphorelays. We discuss the perception of cytokinin by the ER-localized histidine kinase receptors, the role of the AHPs in mediating the transfer of the phosphoryl group from the receptors to the response regulators (ARRs), and finally the role of the large ARR family in cytokinin function. The identification and genetic manipulation of the genes involved in cytokinin metabolism and signaling have helped illuminate the roles of cytokinins in Arabidopsis. We discuss these diverse roles, and how other signaling pathways influence cytokinin levels and sensitivity though modulation of the expression of cytokinin signaling and metabolic genes.
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Affiliation(s)
- Joseph J Kieber
- University of North Carolina, Biology Department, Chapel Hill, NC 27599-3280
| | - G Eric Schaller
- Dartmouth College, Department of Biological Sciences, Hanover, NH 03755
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Immanen J, Nieminen K, Duchens Silva H, Rodríguez Rojas F, Meisel LA, Silva H, Albert VA, Hvidsten TR, Helariutta Y. Characterization of cytokinin signaling and homeostasis gene families in two hardwood tree species: Populus trichocarpa and Prunus persica. BMC Genomics 2013; 14:885. [PMID: 24341635 PMCID: PMC3866579 DOI: 10.1186/1471-2164-14-885] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/27/2013] [Indexed: 01/01/2023] Open
Abstract
Background Through the diversity of cytokinin regulated processes, this phytohormone has a profound impact on plant growth and development. Cytokinin signaling is involved in the control of apical and lateral meristem activity, branching pattern of the shoot, and leaf senescence. These processes influence several traits, including the stem diameter, shoot architecture, and perennial life cycle, which define the development of woody plants. To facilitate research about the role of cytokinin in regulation of woody plant development, we have identified genes associated with cytokinin signaling and homeostasis pathways from two hardwood tree species. Results Taking advantage of the sequenced black cottonwood (Populus trichocarpa) and peach (Prunus persica) genomes, we have compiled a comprehensive list of genes involved in these pathways. We identified genes belonging to the six families of cytokinin oxidases (CKXs), isopentenyl transferases (IPTs), LONELY GUY genes (LOGs), two-component receptors, histidine containing phosphotransmitters (HPts), and response regulators (RRs). All together 85 Populus and 45 Prunus genes were identified, and compared to their Arabidopsis orthologs through phylogenetic analyses. Conclusions In general, when compared to Arabidopsis, differences in gene family structure were often seen in only one of the two tree species. However, one class of genes associated with cytokinin signal transduction, the CKI1-like family of two-component histidine kinases, was larger in both Populus and Prunus than in Arabidopsis.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ykä Helariutta
- Institute of Biotechnology and Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland.
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Gruhn N, Heyl A. Updates on the model and the evolution of cytokinin signaling. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:569-74. [PMID: 24080474 DOI: 10.1016/j.pbi.2013.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Revised: 09/02/2013] [Accepted: 09/02/2013] [Indexed: 05/09/2023]
Abstract
Cytokinins represent a class of phytohormones, which are key players not only in many processes important for plant growth and development, but also in the response to changes in their environment. The model for the cytokinin signaling pathway was established at the turn of the last century and many experiments confirmed its validity. In recent years several changes and extensions to the model were necessary to accommodate new findings concerning its components, such as subcellular localization, selective protein degradation and new modes of cross talk. In addition phylogenetic analyses of components of the cytokinin circuitry started to reveal the origin and evolution of the cytokinin regulatory system.
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Affiliation(s)
- Nijuscha Gruhn
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Germany
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41
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Ren B, Chen Q, Hong S, Zhao W, Feng J, Feng H, Zuo J. The Arabidopsis eukaryotic translation initiation factor eIF5A-2 regulates root protoxylem development by modulating cytokinin signaling. THE PLANT CELL 2013; 25:3841-57. [PMID: 24163315 PMCID: PMC3877783 DOI: 10.1105/tpc.113.116236] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/04/2013] [Accepted: 10/06/2013] [Indexed: 05/07/2023]
Abstract
The phytohormone cytokinin regulates various aspects of plant growth and development, including root vascular development. In Arabidopsis thaliana, mutations in the cytokinin signaling components cause misspecification of protoxylem cell files. Auxin antagonizes cytokinin-regulated root protoxylem differentiation by inducing expression of Arabidopsis phosphotransfer protein6 (AHP6), a negative regulator of cytokinin signaling. However, the molecular mechanism of cytokinin-regulated protoxylem differentiation is not fully understood. Here, we show that a mutation in Arabidopsis fumonisin B1-resistant12 (FBR12), which encodes a eukaryotic translation initiation factor 5A, causes defective protoxylem development and reduced sensitivity to cytokinin. FBR12 genetically interacts with the cytokinin receptor cytokinin response1 (CRE1) and downstream AHP genes, as double mutants show enhanced phenotypes. FBR12 forms a protein complex with CRE1 and AHP1, and cytokinin regulates formation of this protein complex. Intriguingly, ahp6 partially suppresses the fbr12 mutant phenotype, and the fbr12 mutation causes increased expression of AHP6, indicating that FBR12 negatively regulates AHP6. Consistent with this, ectopic expression of FBR12 in the CRE1-expressing domain partially rescues defective protoxylem development in fbr12, and overexpression of AHP6 causes an fbr12-like phenotype. These results define a regulatory role of the highly conserved FBR12 in cytokinin-mediated root protoxylem specification.
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Affiliation(s)
- Bo Ren
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qingguo Chen
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sulei Hong
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenming Zhao
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Feng
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haizhong Feng
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jianru Zuo
- State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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Ramireddy E, Brenner WG, Pfeifer A, Heyl A, Schmülling T. In planta analysis of a cis-regulatory cytokinin response motif in Arabidopsis and identification of a novel enhancer sequence. PLANT & CELL PHYSIOLOGY 2013; 54:1079-92. [PMID: 23620480 DOI: 10.1093/pcp/pct060] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The phytohormone cytokinin plays a key role in regulating plant growth and development, and is involved in numerous physiological responses to environmental changes. The type-B response regulators, which regulate the transcription of cytokinin response genes, are a part of the cytokinin signaling system. Arabidopsis thaliana encodes 11 type-B response regulators (type-B ARRs), and some of them were shown to bind in vitro to the core cytokinin response motif (CRM) 5'-(A/G)GAT(T/C)-3' or, in the case of ARR1, to an extended motif (ECRM), 5'-AAGAT(T/C)TT-3'. Here we obtained in planta proof for the functionality of the latter motif. Promoter deletion analysis of the primary cytokinin response gene ARR6 showed that a combination of two extended motifs within the promoter is required to mediate the full transcriptional activation by ARR1 and other type-B ARRs. CRMs were found to be over-represented in the vicinity of ECRMs in the promoters of cytokinin-regulated genes, suggesting their functional relevance. Moreover, an evolutionarily conserved 27 bp long T-rich region between -220 and -193 bp was identified and shown to be required for the full activation by type-B ARRs and the response to cytokinin. This novel enhancer is not bound by the DNA-binding domain of ARR1, indicating that additional proteins might be involved in mediating the transcriptional cytokinin response. Furthermore, genome-wide expression profiling identified genes, among them ARR16, whose induction by cytokinin depends on both ARR1 and other specific type-B ARRs. This together with the ECRM/CRM sequence clustering indicates cooperative action of different type-B ARRs for the activation of particular target genes.
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Affiliation(s)
- Eswarayya Ramireddy
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences (DCPS), Freie Universität Berlin, Germany
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43
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Del Bianco M, Giustini L, Sabatini S. Spatiotemporal changes in the role of cytokinin during root development. THE NEW PHYTOLOGIST 2013; 199:324-338. [PMID: 23692218 DOI: 10.1111/nph.12338] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/12/2013] [Indexed: 05/07/2023]
Abstract
The root is a dynamic system whose structure is regulated by a complex network of interactions between hormones. The primary root meristem is specified in the embryo. After germination, the primary root meristem grows and then reaches a final size that will be maintained during the life of the plant. Subsequently, secondary structures such as lateral roots and root nodules form via the re-specification of differentiated cells. Cytokinin plays key roles in the regulation of root development. Down-regulation of the cytokinin response is required for the specification of a new stem cell niche, during both embryo and lateral root development. In the root meristem, cytokinin signalling regulates the longitudinal zonation of the meristem by controlling cell differentiation. Moreover, cytokinin regulates radial patterning of root vasculature by promoting protophloem cell identity and by spatially inhibiting protoxylem formation. In this review, an effort is made to describe the known details of the role of cytokinin during root development, taking into account also the interactions between cytokinin and other hormones. Attention is given on the dynamicity of cytokinin signalling output during different developmental events. Indeed, there is much evidence that the effects of cytokinin change as organs grow, underlining the importance of the spatiotemporal specificity of cytokinin signalling.
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Affiliation(s)
- Marta Del Bianco
- Laboratory of Functional Genomics and Proteomics of Model Systems, Dipartimento di Biologia e Biotecnologie, Università di Roma, Sapienza - via dei Sardi, 70-00185, Rome, Italy
| | - Leonardo Giustini
- Laboratory of Functional Genomics and Proteomics of Model Systems, Dipartimento di Biologia e Biotecnologie, Università di Roma, Sapienza - via dei Sardi, 70-00185, Rome, Italy
| | - Sabrina Sabatini
- Laboratory of Functional Genomics and Proteomics of Model Systems, Dipartimento di Biologia e Biotecnologie, Università di Roma, Sapienza - via dei Sardi, 70-00185, Rome, Italy
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Histidine phosphotransfer proteins in fungal two-component signal transduction pathways. EUKARYOTIC CELL 2013; 12:1052-60. [PMID: 23771905 DOI: 10.1128/ec.00083-13] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The histidine phosphotransfer (HPt) protein Ypd1 is an important participant in the Saccharomyces cerevisiae multistep two-component signal transduction pathway and, unlike the expanded histidine kinase gene family, is encoded by a single gene in nearly all model and pathogenic fungi. Ypd1 is essential for viability in both S. cerevisiae and in Cryptococcus neoformans. These and other aspects of Ypd1 biology, combined with the availability of structural and mutational data in S. cerevisiae, suggest that the essential interactions between Ypd1 and response regulator domains would be a good target for antifungal drug development. The goal of this minireview is to summarize the wealth of data on S. cerevisiae Ypd1 and to consider the potential benefits of conducting related studies in pathogenic fungi.
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45
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Kunikowska A, Byczkowska A, Doniak M, Kaźmierczak A. Cytokinins résumé: their signaling and role in programmed cell death in plants. PLANT CELL REPORTS 2013; 32:771-80. [PMID: 23579381 PMCID: PMC3654191 DOI: 10.1007/s00299-013-1436-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/22/2013] [Accepted: 03/25/2013] [Indexed: 05/21/2023]
Abstract
Cytokinins (CKs) are a large group of plant hormones which play a crucial role in many physiological processes in plants. One of the interesting functions of CKs is the control of programmed cell death (PCD). It seems that all CKs-dependent phenomena including PCD are accompanied by special multi-step phosphorelay signaling pathway. This pathway consists of three elements: histidine kinase receptors (HKs), histidine phosphotransfer proteins (HPs) and response regulators (RRs). This review shows the résumé of the latest knowledge about CKs signaling pathways in many physiological processes in plants with special attention paid to PCD process.
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Affiliation(s)
- A. Kunikowska
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/133, 90236 Łódź, Poland
| | - A. Byczkowska
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/133, 90236 Łódź, Poland
| | - M. Doniak
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/133, 90236 Łódź, Poland
| | - A. Kaźmierczak
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/133, 90236 Łódź, Poland
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El-Showk S, Ruonala R, Helariutta Y. Crossing paths: cytokinin signalling and crosstalk. Development 2013; 140:1373-83. [PMID: 23482484 DOI: 10.1242/dev.086371] [Citation(s) in RCA: 171] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cytokinins are a major class of plant hormones that are involved in various aspects of plant development, ranging from organ formation and apical dominance to leaf senescence. Cytokinin and auxin have long been known to interact antagonistically, and more recent studies have shown that cytokinins also interact with other plant hormones to regulate plant development. A growing body of research has begun to elucidate the molecular and genetic underpinnings of this extensive crosstalk. The rich interconnections between the synthesis, perception and transport networks of these plant hormones provide a wide range of opportunities for them to modulate, amplify or buffer one another. Here, we review this exciting and rapidly growing area of cytokinin research.
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Affiliation(s)
- Sedeer El-Showk
- Institute of Biotechnology/Department of Biosciences, University of Helsinki, Helsinki FI-00014, Finland
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47
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Li Y, Kurepa J, Smalle J. AXR1 promotes the Arabidopsis cytokinin response by facilitating ARR5 proteolysis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:13-24. [PMID: 23279608 DOI: 10.1111/tpj.12098] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 12/07/2012] [Accepted: 12/11/2012] [Indexed: 05/26/2023]
Abstract
The plant hormone cytokinin plays essential roles in many aspects of growth and development. The cytokinin signal is transmitted by a multi-step phosphorelay to the members of two functionally antagonistic classes of Arabidopsis response regulators (ARRs): type B ARRs (response activators) and type A ARRs (negative-feedback regulators). Previous studies have shown that mutations in AXR1, encoding a subunit of the E1 enzyme in the RUB (related to ubiquitin) modification pathway, lead to decreased cytokinin sensitivity. Here we show that the cytokinin resistance of axr1 seedlings is suppressed by loss of function of the type A ARR family member ARR5. Based on the established role of the RUB pathway in ubiquitin-dependent proteolysis, these data suggest that AXR1 promotes the cytokinin response by facilitating type A ARR degradation. Indeed, both genetic (axr1 mutants) and chemical (MLN4924) suppression of RUB E1 increased ARR5 stability, suggesting that the ubiquitin ligase that promotes ARR5 proteolysis requires RUB modification for optimal activity.
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Affiliation(s)
- Yan Li
- Plant Physiology, Biochemistry and Molecular Biology Program, Department of Plant and Soil Science, University of Kentucky, Lexington, KY 40546, USA
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48
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Arabidopsis AHP2, AHP3, and AHP5 histidine phosphotransfer proteins function as redundant negative regulators of drought stress response. Proc Natl Acad Sci U S A 2013; 110:4840-5. [PMID: 23487796 DOI: 10.1073/pnas.1302265110] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Cytokinin is an essential phytohormone controlling various biological processes, including environmental stress responses. In Arabidopsis, although the cytokinin (CK)-related phosphorelay--consisting of three histidine kinases, five histidine phosphotransfer proteins (AHPs), and a number of response regulators--has been known to be important for stress responses, the AHPs required for CK signaling during drought stress remain elusive. Here, we report that three Arabidopsis AHPs, namely AHP2, AHP3, and AHP5, control responses to drought stress in negative and redundant manner. Loss of function of these three AHP genes resulted in a strong drought-tolerant phenotype that was associated with the stimulation of protective mechanisms. Specifically, cell membrane integrity was improved as well as an increased sensitivity to abscisic acid (ABA) was observed rather than an alteration in ABA-mediated stomatal closure and density. Consistent with their negative regulatory functions, all three AHP genes' expression was down-regulated by dehydration, which most likely resulted from a stress-induced reduction of endogenous CK levels. Furthermore, global transcriptional analysis of ahp2,3,5 leaves revealed down-regulation of many well-known stress- and/or ABA-responsive genes, suggesting that these three AHPs may control drought response in both ABA-dependent and ABA-independent manners. The discovery of mechanisms of activation and the targets of the downstream components of CK signaling involved in stress responses is an important and challenging goal for the study of plant stress regulatory network responses and plant growth. The knowledge gained from this study also has broad potential for biotechnological applications to increase abiotic stress tolerance in plants.
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Kim J, Jeon J. Cold signaling via the two-component signaling system. MOLECULAR PLANT 2013; 6:15-17. [PMID: 23220944 DOI: 10.1093/mp/sss151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Jungmook Kim
- Department of Bioenergy Science and Technology, Chonnam National University, Buk-Gu, Gwangju 500-757, Korea
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50
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Jeon J, Kim J. Arabidopsis response Regulator1 and Arabidopsis histidine phosphotransfer Protein2 (AHP2), AHP3, and AHP5 function in cold signaling. PLANT PHYSIOLOGY 2013; 161:408-24. [PMID: 23124324 PMCID: PMC3532271 DOI: 10.1104/pp.112.207621] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 11/01/2012] [Indexed: 05/18/2023]
Abstract
The Arabidopsis (Arabidopsis thaliana) two-component signaling system, which is composed of sensor histidine kinases, histidine phosphotransfer proteins, and response regulators, mediates the cytokinin response and various other plant responses. We have previously shown that ARABIDOPSIS HISTIDINE KINASE2 (AHK2), AHK3, and cold-inducible type A ARABIDOPSIS RESPONSE REGULATORS (ARRs) play roles in cold signaling. However, the roles of type B ARRs and ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEINS (AHPs) have not been investigated in cold signaling. Here, we show that ARR1 and AHP2, AHP3, and AHP5 play positive roles in the cold-inducible expression of type A ARRs. arr1 mutants showed greatly reduced cold-responsive expression of type A ARRs compared with the wild type, whereas ARR1-overexpressing Arabidopsis exhibited the hypersensitive cold response of type A ARRs as well as enhanced freezing tolerance with cytokinin, suggesting that ARR1 functions as a positive factor of cold signaling. Transgenic Arabidopsis expressing ARR1ΔDDK:GR lacking the amino-terminal receiver domain showed wild-type expression levels of type A ARRs in response to cold, indicating that the signal receiver domain of ARR1 might be important for cold-responsive expression of type A ARRs. ahp2 ahp3 ahp5 triple mutations greatly reduced type A ARR expression in response to cold, whereas the single or double ahp mutants displayed wild-type levels of ARR expression, suggesting that AHP2, AHP3, and AHP5 are redundantly involved in cold signaling. Taken together, these results suggest that ARR1 mediates cold signal via AHP2, AHP3, or AHP5 from AHK2 and AHK3 to express type A ARRs. We further identified a cold transcriptome affected by ahk2 ahk3 mutations by microarray analysis, revealing a new cold-responsive gene network regulated downstream of AHK2 and AHK3.
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