PLANT PHYSIOLOGY , Vol 115, Issue 1 283-289, Copyright © 1997 by American Society of Plant Biologists
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PLANT-MICROBE AND PLANT-INSECT INTERACTIONS |
Rapid and Transient Induction of a Parsley Microsomal [delta]12 Fatty Acid Desaturase mRNA by Fungal Elicitor
C. Kirsch, K. Hahlbrock and I. E. Somssich
Max-Planck-Institut fur Zuchtungsforschung, Abteilung Biochemie, Carl-von-Linne-Weg 10, D-50829 Koln, Germany
Treatment of cultured parsley (Petroselinum crispum L.) cells with a
structurally defined peptide elicitor (Pep25) of fungal origin has
previously been shown to cause rapid and large changes in the levels of
various desaturated fatty acids. We isolated two distinct parsley cDNAs
sharing high sequence similarity with microsomal [omega]-6 fatty acid
desaturases (FADs). One of them was functionally identified as a [delta]12
FAD by expression in the yeast Saccharomyces cerevisiae. Two dienoic fatty
acids, hexadecadienoic and linoleic, which were not detectable in control
cells, together constituted up to 12% of the total fatty acids in the
transformed yeast cells. [delta]12 FAD mRNA accumulated rapidly and
transiently in elicitor-treated parsley cells, protoplasts, and leaves.
These and previous results indicate that fatty acid desaturation is an
important early component of the complex defense response of parsley to
attempted fungal infection.
