Journal
PLANT SCIENCE
Volume 287, Issue -, Pages -Publisher
ELSEVIER IRELAND LTD
DOI: 10.1016/j.plantsci.2019.110190
Keywords
Arabidopsis; MAPK cascade; MKK7; MKK9; Salt stress; Phosphatidic acid
Categories
Funding
- National Natural Science Foundation of China [31570270, 31400234]
- Fundamental Research Funds for the Central Universities [KJQN201531]
- Ministry of Science and Technology in China [2015BAD01B01]
- Jiangsu province (PAPD)
Ask authors/readers for more resources
Phosphatidic acid (PA) is a lipid secondary messenger involved in intracellular signaling in eukaryotes. It has been confirmed that PA mediates salt stress signaling by promoting activation of Mitogen-activated Protein Kinase 6 (MPK6) which phosphorylates Na+/H+ antiporter SOS1. However, the MPK6-upstream kinases and their relationship to PA remain unclear. Here, we found that, among the six tested Arabidopsis Mitogen-activated Protein Kinase Kinases (MKKs), PA specifically bound to MKK7 and MKK9 which phosphorylate MPK6, and promoted the activation of MKK7/MKK9. Based on phenotypic and physiological analyses, we found that MKK7 and MKK9 positively regulate Arabidopsis salt tolerance and are functionally redundant. NaCl treatment can induce significant increase in MKK7/MKK9 activities, and this depends, in part, on the Phospholipase D alpha 1 (PLD alpha 1). MKK7 and MKK9 also mediate the NaCl-induced activation of MPK6. Furthermore, PA or NaCl treatment could induce translocation of MKK7/MKK9 to the plasma membrane, whereas this translocation disappeared in pld alpha 1. These results indicate that PA binds to MKK7 and MKK9, increases their kinase activity and plasma membrane localization during Arabidopsis response to salt stress. Together with the PA-MPK6-SOS1 pathway identified previously, this mechanism may maximize the signal transduction efficiency, providing novel insights into the link between lipid signaling and MAPK cascade.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available