Activation of MKK9-MPK3/MPK6 enhances phosphate acquisition in Arabidopsis thaliana
- PMID: 24865627
- DOI: 10.1111/nph.12872
Activation of MKK9-MPK3/MPK6 enhances phosphate acquisition in Arabidopsis thaliana
Abstract
Despite the abundance of phosphorus in soil, very little is available as phosphate (Pi) for plants. Plants often experience low Pi (LP) stress. Intensive studies have been conducted to reveal the mechanism used by plants to deal with LP; however, Pi sensing and signal transduction pathways are not fully understood. Using in-gel kinase assays, we determined the activities of MPK3 and MPK6 in Arabidopsis thaliana seedlings under both LP and Pi-sufficient (Murashige and Skoog, MS) conditions. Using MKK9 mutant transgenic and crossed mutants, we analyzed the functions of MPK3 and MPK6 in regulating Pi responses of seedlings. The regulation of Pi responses by downstream components of MKK9-MPK3/MPK6 was also screened. LP treatment activated MPK3 and MPK6. Under both LP and MS conditions, mpk3 and mpk6 seedlings took up and accumulated less Pi than the wild-type; activation of MKK9-MPK3/MPK6 in transgenic seedlings induced the transcription of Pi acquisition-related genes and enhanced Pi uptake and accumulation, whereas its activation suppressed the transcription of anthocyanin biosynthetic genes and anthocyanin accumulation; WRKY75 was downstream of MKK9-MPK3/MPK6 when regulating the accumulation of Pi and anthocyanin, and the transcription of Pi acquisition-related and anthocyanin biosynthetic genes. These results suggest that the MKK9-MPK3/MPK6 cascade is part of the Pi signaling pathway in plants.
Keywords: Arabidopsis thaliana; MKK9; MPK3; MPK6; Pi responses; phosphate; signal transduction pathway.
© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.
References
-
- Alvarez E, Northwood IC, Gonzalez FA, Latour DA, Seth A, Abate C, Curran T, Davis RJ. 1991. Pro-Leu-Ser/Thr-Pro is a consensus primary sequence for substrate protein phosphorylation. Journal of Biological Chemistry 266: 15277-15285.
-
- Ames BN. 1966. Assay of inorganic phosphate, total phosphate and phosphatases. Methods in Enzymology 8: 115-118.
-
- Andreasson E, Ellis B. 2010. Convergence and specificity in the Arabidopsis MAPK nexus. Trends in Plant Science 15: 106-113.
-
- Asai T, Tena G, Plotnikova J, Willmann MR, Chiu WL, Gomez-Gomez L, Boller T, Ausubel FM, Sheen J. 2002. MAP kinase signalling cascade in Arabidopsis innate immunity. Nature 415: 977-983.
-
- Aung K, Lin SI, Wu CC, Huang YT, Cl Su, Chiou TJ. 2006. pho2, a phosphate overaccumulator, is caused by a nonsense mutation in a MicroRNA399 target gene. Plant Physiology 141: 1000-1011.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Other Literature Sources
Molecular Biology Databases
Research Materials
Miscellaneous
