Reference "A novel lipoxygenase from rice. Primary structure and specific expression upon incompatible infection with rice blast fungus"

Reference ID

3431

Title

A novel lipoxygenase from rice. Primary structure and specific expression upon incompatible infection with rice blast fungus

Source

The Journal of biological chemistry, 1994, vol. 269, pp. 3755-3761

Authors (6)

Peng-Y-L	Shirano-Y
Ohta-H	Hibino-T
Tanaka-K	Shibata-D

Abstract

A novel lipoxygenase cDNA (3,007 base pairs) was isolated from rice leaves
(Oryza sativa cv. Aichiasahi) which had been infected with an incompatible race
of the rice blast fungus, Magnaporthe grisea. A single copy of the gene is
present in the rice genome and encodes a protein of 923 residues with a
molecular weight of 102,714. This gene product shares the least amino acid
sequence homology among plant lipoxygenases identified to date. A novel feature
of this gene product is a putative transit peptide sequence at the amino
terminus, suggesting the enzyme is localized in chloroplasts. An active
lipoxygenase was expressed from the cDNA in Escherichia coli and characterized.
The lipoxygenase introduces molecular oxygen exclusively into the C-13 position
of linoleic and linolenic acids. The gene is expressed at high levels 15 h after
inoculation with an incompatible race of M. grisea, at a low level after
inoculation with a compatible race of the pathogen, and is not expressed in mock-
infected leaves. Gene expression begins at the same time that the pathogen
begins to penetrate into leaf tissue. This novel lipoxygenase gene expression is
a part of the early response of the host to pathogenic attack.