GhMPK7, a novel multiple stress-responsive cotton group C MAPK gene, has a role in broad spectrum disease resistance and plant development.
Mitogen-activated protein kinase (MAPK) cascades play a pivotal role in environmental responses and developmental processes in plants. Previous researches mainly focus on the MAPKs in groups A and B, and little is known on group C. In this study, we isolated and characterized GhMPK7, which is a novel gene from cotton belonging to the group C MAPK. RNA blot analysis indicated that GhMPK7 transcript was induced by pathogen infection and multiple defense-related signal molecules. Transgenic Nicotina benthamiana overexpressing GhMPK7 displayed significant resistance to fungus Colletotrichum nicotianae and virus PVY, and the transcript levels of SA pathway genes were more rapidly and strongly induced. Furthermore, the transgenic N. benthamiana showed reduced ROS-mediated injuries by upregulating expression of oxidative stress-related genes. Interestingly, the transgenic plants germinated earlier and grew faster in comparison to wild-type plants. beta-glucuronidase activity driven by the GhMPK7 promoter was detected in the apical meristem at the vegetative stage, and it was enhanced by treatments with signal molecules and phytohormones. These results suggest that GhMPK7 might play an important role in SA-regulated broad-spectrum resistance to pathogen infection, and that it is also involved in regulation of plant growth and development.
Shi
Jing
J
Shandong Agricultural University, Tai'an, People's Republic of China.
An
Hai-Long
HL
Zhang
Liang
L
Gao
Zheng
Z
Guo
Xing-Qi
XQ
D000595:Amino Acid Sequence; D017360:Arabidopsis; D001483:Base Sequence; D003001:Cloning, Molecular; D020231:Colletotrichum / Q000472:pathogenicity; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D003368:Gossypium / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D020928:Mitogen-Activated Protein Kinases / Q000145:classification / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology / Q000821:virology; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D017382:Reactive Oxygen Species / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological; D014026:Nicotiana
D017931:DNA Primers; D018076:DNA, Complementary; D018744:DNA, Plant; D017382:Reactive Oxygen Species; D011993:Recombinant Fusion Proteins; D020928:Mitogen-Activated Protein Kinases