Rl. Garifullina et al., Spin-label study of the microtubule modifier effect on the aqueous-medium microviscosity of nonhardened and cold-hardened winter wheat seedlings, APPL MAGN R, 16(4), 1999, pp. 559-563
The influence of the substances modifying the microtubule structure, colchi
cine and dimethyl sulfoxide (DMSO), on the aqueous-medium microviscosity of
nonhardened and cold-hardened winter wheat seedlings has been studied with
a spin label (1-oxyl-2,2,6,6-tetramethyl-4-oxypiperidine). The correlation
times tau(c) of rotational diffusion of the labels were found with values
for the cold-hardened plants lower than those for the plants grown in optim
al temperature conditions. In case of nonhardened tissues colchicine gives
the slight increase and DMSO causes the slight decrease of tau(c) values in
comparison with data for control variant without any treatment. It was exp
lained by opposite changes in plasma membrane permeability and/or hydration
or dehydration of cytoskeleton under the treatments. However, these substa
nces do not influence the aqueous medium microviscosity of cold-hardened se
edlings. This fact indicates the essential change of the tubulin proteins u
nder cold exposure.