1021-4437/01/4801- $25.00 © 2001
Russian Journal of Plant Physiology, Vol. 48, No. 1, 2001, pp. 89–94. Translated from Fiziologiya Rastenii, Vol. 48, No. 1, 2001, pp. 106–112.
Original Russian Text Copyright © 2001 by Voinikov, Grabel’nykh, Kolesnichenko, Pobezhimova.
Plants respond to low temperatures with diverse
physiological and biochemical changes in cell metabo-
lism. A speciﬁc plant response to temperature stress
that provides for their adaptation is the synthesis of
stress proteins . By analogy with the heat-shock pro-
teins, proteins synthesized in response to plant chilling
were called cold-shock proteins . It is believed that
CSP play an important role in the development of plant
tolerance to low temperatures [3–5]. By now, several
families of CSP with speciﬁc functions are established.
The ﬁrst group comprises chaperonins and dehydrins,
which protect macromolecules and plant-cell mem-
branes against dehydration during hypothermia .
The second group consists of antifreeze proteins
secreted by plant cells into the apoplast and intercellu-
lar space . They prevent the formation of large ice
crystals during the freezing of extracellular water, thus
protecting cells from injury . Finally, there are pro-
teins uncoupling respiratory oxidation and phosphory-
lation [9, 10].
Previously, we isolated a CSP with a mol wt of
310 kD from winter rye seedlings . Proteins of this
family were also found in other cereals . They are
located in nuclei, cytoplasm, and mitochondria . It
may be that CSP310 is involved in uncoupling between
respiratory oxidation and phosphorylation . This
suggestion is based on data indicating the operation of
a mechanism protecting plants against low-temperature
stress  that was previously believed to function only
in mammals .
It is well known that chilling of warm-blooded ani-
mals induces thermogenesis due to uncoupling of oxi-
dative phosphorylation . It turned out that thermo-
genesis is a much more common phenomenon and
occurs not only in animals but also in plants, for exam-
ple, in some ﬂowering plants  and during the initial
period of chilling of wintering cereal crops . The
cause of thermogenesis in both plants and animals is
the uncoupling of oxidative phosphorylation, which is
related to the activity of free fatty acids. FA accumulate
in plant mitochondria due to cold-induced activation of
. It was suggested that uncou-
pling between oxidation and phosphorylation in mito-
chondria of winter cereals might involve uncoupling
proteins . A set of such proteins, which were
homologous to uncoupling proteins from animals, was
later found in plant tissues [9, 18, 19].
The location of CSP310 in plant mitochondria 
permits the suggestion that this protein might affect
mitochondrial energetic activity during hypothermia.
In this connection, the objective of this work was to
verify this suggestion and to examine the possible
uncoupling function of CSP310.
MATERIALS AND METHODS
Three-day-old etiolated seedlings of
winter wheat (
L., cv. Zalarinka),
winter rye (
L., cv. Dymka), and maize
L, hybrid VIR 36), and also six-day-old pea
Cold-Shock 310-kD Protein Uncouples Oxidative Phosphorylation
in Plant Mitochondria
V. K. Voinikov, O. I. Grabel’nykh, A. V. Kolesnichenko, and T. P. Pobezhimova
Siberian Institute of Plant Physiology and Biochemistry, Siberian Division, Russian Academy of Sciences,
ul. Lermontova 132, Irkutsk, 664033 Russia;
fax: 7 (3952) 51-0754; e-mail: VVK@siﬁbr.irk.ru
Received March 13, 2000
—We studied the effects of cold-shock 310-kD protein (CSP310) isolated from winter rye seedlings
on the energetic activity of plant mitochondria. CSP310 was shown to enhance nonphosphorylating respiration
and uncoupled oxidative phosphorylation in isolated mitochondria. The uncoupling effect was enhanced with
increasing protein concentration. An antibody against CSP310 interfered with the uncoupling effect of CSP310.
Free fatty acids were not evidently involved in uncoupling. The physiological role of uncoupling between oxi-
dation and phosphorylation during plant adaptation to low temperatures is discussed.
Key words: Triticum aestivum - Secale cereale - Zea mays - Pisum sativum - mitochondria - uncoupling oxida-
tion and phosphorylation - cold-shock 310-kD protein
: BSA—bovine serum albumin; CSP—cold-shock
protein(s); FA—fatty acids; Mops—3(N-morpholino)propane-