ISSN 10214437, Russian Journal of Plant Physiology, 2013, Vol. 60, No. 1, pp. 77–83. © Pleiades Publishing, Ltd., 2013.
Original Russian Text © A.N. Levchuk, E.N. Voitovich, V.A. Lyakh, 2013, published in Fiziologiya Rastenii, 2013, Vol. 60, No. 1, pp. 75–81.
Due to the lack of mobility, plant organisms cannot
avoid unfavorable effects of environmental factors;
therefore, they have to adapt to new environmental
conditions by changing their metabolism [1, 2].
Development of plant resistance to some extent
depends on lectins (glycoproteins capable of recogniz
ing and binding carbohydrates located on cell sur
faces) . Lectins are quantitatively described by lec
tin activity (minimum protein concentration that
shows biological activity) and qualitatively by carbo
hydrate specificity (the ability to recognize particular
carbohydrates) [4, 5]. According to their location
within the cell, lectins are subdivided into three
groups: membrane (located in cytoplasmic membrane
and the membranes of organelles), soluble (located in
cytosol and vacuolar sap), and cell wall lectins [4, 6].
The role of lectins of different cellular fractions in
adaptation to abiotic stress was shown in several crops
. For instance, lectins of cell walls and organelle
membranes participate in the development of resis
tance to low temperatures [8, 9] and soluble and mem
brane lectins—to salinity [10–14].
The aim of this work was to look into the changes in
characteristics of oilseed flax lectins depending on
total level of nonspecific resistance at early develop
mental stages and on the extent of plant adaptation to
such abiotic stress factors as hypo and hyperthermia,
osmotic stress, and sodium chloride salinity associated
with osmotic stress.
MATERIALS AND METHODS
The experiments were conducted with 7dold eti
olated seedlings of oilseed flax (
representing six genotypes (cvs. Tsian, Antares, Ais
berg, Avangard, Astral, and Zolotistyi), with different
extent of adaptation to particular abiotic stress factors
. The seeds were preliminarily germinated for
5 days in Petri dishes on filter paper moistened with
distilled water at room temperature (
) in the dark.
In order to produce hypo and hyperthermia, 5d
old seedlings were kept for 24 h at 4 and
tively. To simulate osmotic stress, the medium was
supplemented with sucrose up to 15% (–1.13 MPa) or
sodium chloride to 3% (–2.24 MPa). In the latter
case, osmotic stress was associated with toxic effect of
salts (salinity). In these solutions, the seedlings were
incubated for 24 h.
Lectins were extracted from whole 7dold seed
lings after 24hlong exposure to stress and subsequent
Lectin extracts were described by quantitative (lec
tin activity) and qualitative (carbohydrate specificity)
Lectins of OilSeed Flax Plants Exposed to Abiotic Stress
A. N. Levchuk, E. N. Voitovich, and V. A. Lyakh
Zaporozhye National University, ul. Zhukovskogo 66, Zaporozhye, 69041 Ukraine;
Received November 4, 2011
—The seedlings of six cultivars of oilseed flax (
Mill.) differing in the extent of adap
tation to abiotic stresses (hypo and hyperthermia, osmotic stress, and salinity) were used to assess hemag
glutination activity and carbohydrate specificity of total lectin preparations extracted from various cell com
partments. In the course of adaptation of plants resistant to hyperthermia, osmotic stress and salinity, we
observed a considerable rise in the coefficient of activity of membrane lectins, whereas the adaptation to
hypothermia elevated the coefficient of activity of cell wall lectins. As to total soluble lectins, the adaptation
of flax plants was associated with the changes in the range of their carbohydrate specificity. For instance, fol
lowing the adaptation to hyperthermia, they were found to bind glucose and glucosamine, to osmotic stress—
mannose and xylose, to salinity—galactose, glucose, and glucosamine; after cold resistance was developed,
total soluble lectins were found to recognize lactose and fructose. It was concluded that lectins may partici
pate in specific adaptation of flax plants to various abiotic stress factors.
Keywords: Linum humile
, adaptation, abiotic stress, hypo and hyperthermia, osmotic stress, salinity, range
of carbohydrate specificity, lectins
: LA—lectin activity.