[Seasonal changes in the composition of the titin isoforms in muscles of hibernating ground squirrels].
An electrophoretic study of changes in the content of intact titin isoforms, N2B-, N2BA-, N2A-titins and T2 in skeletal and cardiac muscles of ground squirrel (Spermophillus undulatus) in different periods: summer activity, autumn activity, hibernation, arousal, and winter activity has been carried out. In atriums and ventricles of autumn activity ground squirrels, an increase (approximately 1.5 times) in the N2BA-to-N2B ratio in comparison with that in cardiac muscle of summer activity ground squirrels has been observed. During hibernation, the decrease in the relative content of N2B,- N2BA-titins and T2 in cardiac muscle and of N2A-titin and T2 in skeletal muscles has been tested against the background of preservation of the relative amount of intact titin isoforms. During arousal of ground squirrel and in short-time period of winter activity, a rapid restoration in the content of N2B,- N2BA-, N2A-titins and T2 in muscles has been observed. In this case, in cardiac muscle of hibernating, arousing and winter active ground squirrels, the increased N2BA-to-N2B ratio has been preserved. The changes in the titin content are discussed in the context of adaptation of ground squirrels to hibernation.
Vikhliantsev
I M
IM
Karaduleva
E V
EV
Podlubnaia
Z A
ZA
D000818:Animals; D064211:Connectin; D004591:Electrophoresis, Polyacrylamide Gel; D006605:Hibernation; D009124:Muscle Proteins / Q000737:chemistry*; D018482:Muscle, Skeletal / Q000737:chemistry*; D009206:Myocardium / Q000737:chemistry*; D020033:Protein Isoforms / Q000737:chemistry; D011494:Protein Kinases / Q000737:chemistry*; D012589:Sciuridae; D012621:Seasons
D064211:Connectin; D009124:Muscle Proteins; D020033:Protein Isoforms; D011494:Protein Kinases