title: The Cotton Mitogen-Activated Protein Kinase Kinase 3 Functions in Drought Tolerance by Regulating Stomatal Responses and Root Growth.
abstract: Mitogen-activated protein kinase (MAPK) cascades play critical roles in signal transduction processes in eukaryotes. The MAPK kinases (MAPKKs) that link MAPKK kinases (MAPKKKs) and MAPKs are key components of MAPK cascades. However, the intricate regulatory mechanisms that control MAPKKs under drought stress conditions are not fully understood, especially in cotton (Gossypium hirsutum) Here, we isolated and characterized the cotton group B MAPKK gene GhMKK3 Overexpressing GhMKK3 in Nicotiana benthamiana enhanced tolerance to drought, and the results of RNA sequencing (RNA-seq) and quantitative real-time PCR (qRT-PCR) assays suggest that GhMKK3 plays an important role in responses to abiotic stresses by regulating stomatal responses and root hair growth. Further evidence demonstrated that overexpressing GhMKK3 promoted root growth and ABA-induced stomatal closure. In contrast, silencing GhMKK3 in cotton using virus-induced gene silencing (VIGS) resulted in the opposite phenotypes. More importantly, we identified an ABA- and drought-induced MAPK cascade that is composed of GhMKK3, GhMPK7 and GhPIP1 that compensates for deficiency in the MAPK cascade pathway in cotton under drought stress conditions. Together, these findings significantly improve our understanding of the mechanism by which GhMKK3 positively regulates drought stress responses.
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: He
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Yuli
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China.
authors.forename: Xulei
authors.initials: X
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, PR China xqguo@sdau.edu.cn.
authors.forename: Xingqi
authors.initials: X
authors.lastname: Guo
mesh_terms: D055864:Droughts; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D018525:Germination; D003368:Gossypium / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D048371:MAP Kinase Kinase 3 / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D054046:Plant Stomata / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D020798:Two-Hybrid System Techniques
chemical_list: D010940:Plant Proteins; D012965:Sodium Chloride; D048371:MAP Kinase Kinase 3
keywords: Drought stress; Gossypium hirsutum mitogen-activated protein kinase kinase 3 (GhMKK3); MAPK cascade; Root growth; Stomata