title: A maize mitogen-activated protein kinase kinase, ZmMKK1, positively regulated the salt and drought tolerance in transgenic Arabidopsis.
abstract: Mitogen-activated protein kinase (MAPK) cascades are highly conserved signal transduction modules in animals, plants and yeast. MAPK cascades are complicated networks and play vital roles in signal transduction pathways involved in biotic and abiotic stresses. In this study, a maize MAPKK gene, ZmMKK1, was characterized. Quantitative real time PCR (qRT-PCR) analysis demonstrated that ZmMKK1 transcripts were induced by diverse stresses and ABA signal molecule in maize root. Further study showed that the ZmMKK1-overexpressing Arabidopsis enhanced the tolerance to salt and drought stresses. However, seed germination, post-germination growth and stomatal aperture analysis demonstrated that ZmMKK1 overexpression was sensitive to ABA in transgenic Arabidopsis. Molecular genetic analysis revealed that the overexpression of ZmMKK1 in Arabidopsis enhanced the expression of ROS scavenging enzyme- and ABA-related genes, such as POD, CAT, RAB18 and RD29A under salt and drought conditions. In addition, heterologous overexpression of ZmMKK1 in yeast (Saccharomyces cerevisiae) improved the tolerance to salt and drought stresses. These results suggested that ZmMKK1 might act as an ABA- and ROS-dependent protein kinase in positive modulation of salt and drought tolerance. Most importantly, ZmMKK1 interacted with ZmMEKK1 as evidenced by yeast two-hybrid assay, redeeming a deficiency of MAPK interaction partners in maize.
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors: Guohua
authors: G
authors: Cai
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors: Guodong
authors: G
authors: Wang
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors: Li
authors: L
authors: Wang
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors: Yang
authors: Y
authors: Liu
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China.
authors: Jiaowen
authors: J
authors: Pan
authors: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an 271018, Shandong, China. Electronic address: b00011@sdau.edu.cn.
authors: Dequan
authors: D
authors: Li
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D002374:Catalase / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D018525:Germination / Q000187:drug effects; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism*; D009997:Osmotic Pressure / Q000187:drug effects; D009195:Peroxidase / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000033:anatomy & histology / Q000187:drug effects; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology; D030821:Plants, Genetically Modified; D011485:Protein Binding / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D055049:Salt Tolerance / Q000235:genetics*; D012639:Seeds / Q000187:drug effects / Q000254:growth & development; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects; D020798:Two-Hybrid System Techniques; D003313:Zea mays / Q000201:enzymology*
chemical_list: D010940:Plant Proteins; D017382:Reactive Oxygen Species; D012965:Sodium Chloride; D000040:Abscisic Acid; D002374:Catalase; D009195:Peroxidase; D020929:Mitogen-Activated Protein Kinase Kinases
keywords: Expression analysis; MAPK cascades; Salt and drought stresses; Sensitivity; ZmMKK1