ISSN 10214437, Russian Journal of Plant Physiology, 2014, Vol. 61, No. 1, pp. 105–111. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © A.G. Ponomarev, T.D. Tatarinova, A.A. Perk, I.V. Vasilieva, V.V. Bubyakina, 2014, published in Fiziologiya Rastenii, 2014, Vol. 61, No. 1, pp. 114–120.
Plants inhabiting Yakutia can survive under condi
tions of extreme low temperatures and summer
drought. Sharply continental climate of the region is
characterized by a large amplitude of fluctuations in
the absolute maximum and minimum temperatures
, while winter temperatures can
reach up to
. Such climate severity is unique
to the entire Northern Hemisphere, which determines
the rarity of woody plants among life forms of the
Asian white birch (
the main forestforming deciduous species in Central
Yakutia. It takes about 2% of the forest territories and
is involved together with coniferous species in the for
mation of ecosystems stabilizing the cryolithic zone.
Its adaptive potential is not inferior to that of Cajander
Mayr), the world’s most frost
resistant tree, the dominant of the East Siberian taiga.
. Together with this species, Asian white birch pen
etrates to the very North of Eurasia. Its ecological flex
ibility is directly related to the genetic polymorphism,
also observed at the level of the polymorphism of a
number of proteins  creating a species mobilization
reserve ensuring the optimal adaptation of individual
populations at any given point of time.
The development of woody plant frost resistance is
triggered by a short photoperiod and low temperature.
Plant cold acclimation is associated with specific
genes, which expression results in the changes of
metabolism and physiological functions, in particular
the levels of phytohormones and antioxidants,
osmolytes and defense proteins, including chaper
ones, and also proteins with unknown functions [4, 5].
Among defense proteins, dehydrins induce a special
interest; they are group II of late embryogenesis pro
teins. Dehydrins accumulate in plant tissues in
response to osmotic stress induced by water shortage,
low temperature, and high salinity [6, 7].
Dehydrins are highly hydrophilic proteins com
prising conserved K, Y, and Ssegments . In vitro
experiments showed that dehydrins fulfill numerous
functions (chaperone, cryoprotective, antifreeze, rad
icalscavenging, and ionbinding) . Direct evi
dence for dehydrin defensive role was also reported
. The analysis of woody plants inhabiting temperate
climate zones showed that they contain much dehy
drins in winter and low amounts of dehydrins during
active growth. It is supposed that dehydrins are
involved in the cell defense in overwintering plants,
when water exits from the cytoplasm and extracellular
ice is formed . Dehydrins can be used as indirect
stress markers, in particular, markers of frost resistance
. Some dehydrins isolated from separate birch
organs have been identified by us earlier [10, 11].
The objective of this work was to reveal specific fea
tures of intraspecies polymorphism and seasonal vari
ation of dehydrins associated with the development of
Dehydrins Associated with the Development of Frost Resistance
of Asian White Birch
A. G. Ponomarev, T. D. Tatarinova, A. A. Perk, I. V. Vasilieva, and V. V. Bubyakina
Institute of Biological Problems of Cryolithozone, Siberian Branch, Russian Academy of Sciences,
pr. Lenina 41, Yakutsk, 677980 Russia;
Received December 28, 2012
—Seasonal changes in the content of dehydrins in Asian white birch (
growing under extreme cold conditions of Eastern Siberia (Central Yakutia) were studied for the first time by
SDSPAGE and immunoblotting. Several polypeptides, including putative storage proteins, which content
was higher in winter than in other periods, were observed. Intraspecies polymorphism of dehydrins was
detected during plant dormancy. The two groups of dehydrins were found: dehydrins with mol wts of 56–
73 kD, which were present yearround, and dehydrins with mol wts of 15–21 kD, evidently related to the
development of frost resistance because they were absent in summer but present in large amounts in winter.
Under low winter temperatures, the highest level of dehydrins coincided with the lowest content of water in
buds, which was accompanied by increased plant frost resistance to the highest values.
Keywords: Betula platyphylla
, cryolithic zone of Yakutia, frost resistance, dehydrins, seasonal variation,