Abscisic acid and hydrogen peroxide induce a novel maize group C MAP kinase gene, ZmMPK7, which is responsible for the removal of reactive oxygen species.
Mitogen-activated protein kinase (MAPK) cascades are involved in biotic and abiotic stress responses. In plants, MAPKs are classified into four groups, designated A-D. Information about group C MAPKs is limited, and, in particular, no data from maize are available. In this article, we isolated a novel group C MAPK gene, ZmMPK7, from Zea mays. Exogenous abscisic acid (ABA) and hydrogen peroxide (H(2)O(2)) induced calcium-dependant transcription of ZmMPK7. Induction of this gene in response to ABA was blocked by several reactive oxygen species (ROS) manipulators such as imidazole, Tiron, and dimethylthiourea (DMTU). This result indicates that endogenous H(2)O(2) may be required for ZmMPK7-mediated ABA signaling. Expression of ZmMPK7 in Nicotonia tobaccum caused less H(2)O(2) to accumulate and alleviated ROS-mediated injuries following submission of the plants to osmotic stress. The enhanced total peroxidase (POD) activity in transgenic tobacco plants may contribute to removal of ROS. Finally, we have shown that the ZmMPK7 protein localizes in the nucleus. These results broaden our knowledge regarding plant group C MAPK activity in response to stress signals.
Zong
Xiao-juan
XJ
Shandong Agricultural University, 271018, Taian, Shandong, People's Republic of China.
Li
Da-peng
DP
Gu
Ling-kun
LK
Li
De-quan
DQ
Liu
Li-xia
LX
Hu
Xiao-li
XL
D000040:Abscisic Acid / Q000494:pharmacology*; D002467:Cell Nucleus / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D013312:Stress, Physiological; D014026:Nicotiana / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects; D003313:Zea mays / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics
D010937:Plant Growth Regulators; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; D020928:Mitogen-Activated Protein Kinases