Unsaturated fatty acids inhibit MP2C, a protein phosphatase 2C involved in the wound-induced MAP kinase pathway regulation
Article first published online: 1 MAY 2002
The Plant Journal
Volume 20, Issue 3, pages 343–348, November 1999
How to Cite
Baudouin, E., Meskiene, I. and Hirt, H. (1999), Unsaturated fatty acids inhibit MP2C, a protein phosphatase 2C involved in the wound-induced MAP kinase pathway regulation. The Plant Journal, 20: 343–348. doi: 10.1046/j.1365-313X.1999.00608.x
- Issue published online: 1 MAY 2002
- Article first published online: 1 MAY 2002
- Received 6 July 1999; revised 20 September 1999; accepted 20 September 1999.
When mechanically injured, plants develop multiple defense systems including the activation of specific genes. These responses are triggered by a complex network of signalling events that include Ca2+ fluxes, the production of free fatty acids from membrane lipids, as well as the activation of mitogen-activated protein kinases (MAPK). In the present paper, we address the question of the regulation of the MAPK pathway by wound-induced Ca2+ and fatty acid signals. We report that MP2C, a serine/threonine protein phosphatase 2C from alfalfa involved in MAPK pathway inactivation, is inhibited specifically in vitro by long-carbon-chain polyunsaturated fatty acids, and α-linolenic acid, the primary product of the octadecanoid pathway, was found to be the most potent inhibitor. Ca2+ also inhibits MP2C, but only at high concentrations, and other divalent cations show similar inhibitory effect, making it unlikely that Ca2+ is involved in the regulation of MP2C in vivo. Overall, our data suggest that cross-talk between wound-induced MAPK and octadecanoid pathways may occur at the level of protein phosphatase 2C and linolenic acid.