1021-4437/02/4904- $27.00 © 2002
Russian Journal of Plant Physiology, Vol. 49, No. 4, 2002, pp. 541–544. Translated from Fiziologiya Rastenii, Vol. 49, No. 4, 2002, pp. 603–607.
Original Russian Text Copyright © 2002 by Rozhnova, Gerashenkov, Babosha.
Polyunsaturated fatty acids are known to be meta-
bolic precursors to highly effective biological regula-
tors of prostaglandin nature in humans and animals [1,
2]. Aerobic oxidation of PUFAs, such as AA, leads to
the formation of hydroperoxy- and epoxyderivatives,
which are subjected to enzymatic conversion into the
cascade of leukotrienes, which act as potent biological
regulators of signal transduction in animals [3, 4].
The data concerning the molecular mechanisms pro-
viding for the localization and inhibition of viral infec-
tions by plants and the development of acquired sys-
temic resistance are rather contradictory, although
researchers work with diverse model systems. Antiviral
AA action is still not well studied  and is, therefore,
the subject of increased attention. Lectins, that is, pro-
teins speciﬁcally interacting with the carbohydrate res-
idues of glycoconjugates, play an important role in
these processes. Lectin (phytohemagglutinin) activity
was shown to increase during the development of resis-
tance to avirulent pathogens or after treatment with
elicitors . The evidence concerning the involvement
of potato lectins in the resistance processes is scarce.
The inoculation of potato tubers with PVX was shown
to elevate the level of lectins by 60%. The lectins of
infected plants differed in their isoelectric point, the
content of hydroxyproline, and some other properties
. Recent studies demonstrated that
are very promising for investigations of the mecha-
nisms of induced systemic antiviral resistance [8–12].
The goal of this work was to study the physiological
action of the elicitor of lipid nature on
plants, which manifest a relative resistance to phytovi-
MATERIALS AND METHODS
Two-week-old virus-free potato plants (
, cv. Nevskii) grown in tubes were used. Cv.
Nevskii shows a moderate resistance to viruses .
The collection was propagated by cuttings from the
central part of
plants (2–3 cm in length with one
axillary bud). Plants were grown in glass tubes (20
200 mm) sealed with cotton plugs on the Murashige–
Skoog medium (1 ml). Hormones (auxins and cytoki-
nins), vitamins, casein hydrolyzate, and ferulic acid
were not used.
Growth conditions were as follows: scattered light
at an illuminance of 9–10 klx, a day length of 16 h, a
day/night temperature of 22–23/20
C, and a humidity
of 70%. The purity of the virus preparations was tested
by the ELISA technique, using diagnostic monovalent
kits according to manufacturers’ protocols . Virus
concentration was determined using a calibrating curve
built with puriﬁed viral preparations.
Common strains of various phytoviruses were used
for plant inoculation: tobamovirus (TMV), potexvirus
(PVX), carlavirus (PVM), and potyvirus (PVY).
Induction of Phytohemagglutinin Activity
by Arachidonic Acid in
N. A. Rozhnova*, G. A. Gerashenkov*, and A. B. Babosha**
*Institute of Biochemistry and Genetics, Ufa Research Center, Russian Academy of Sciences,
pr. Oktyabrya 69, Ufa, Bashkortostan, 450054 Russia;
fax: 7 (3472) 3561-00; e-mail: email@example.com
**Main Botanical Garden, Russian Academy of Sciences, Moscow
Received July 23, 2001
—Tube-grown potato (
L., cv. Nevskii) plants treated with arachidonic acid (AA)
were used as a model to study the activity of phytohemagglutinins (PHA) during induction of the plant antiviral
defense system. Plant treatment with 10
M AA and also their inoculation with potato viruses X, Y, and M
resulted in the increased activity of PHAs in potato shoots. The inducer of antiviral resistance behaved as a mod-
ulator of the PHA activity providing for its various levels during the development of viral infection. During the
development of AA-induced systemic resistance, the level of phytohemagglutinin activity did not essentially
depend on the nature of the viral pathogen. We suggested that the mechanism of AA-induced plant antiviral
defense was connected with changes in the PHA activity.
Key words: Solanum tuberosum - arachidonic acid - phytohemagglutinins (lectins) - phytoviruses - antiviral
: AA—arachidonic acid; PHA—phytohemaggluti-
nin; PUFA—polyunsaturated fatty acid; PVM—potato virus M;
PVX—potato virus X; PVY—potato virus Y; TMV—tobacco