Tag Archives: proteasome

RNA interference of proteasome subunit of PSMβ7 gene restricts proteasome subunit PSMβ1 and PSMβ5 mRNA expression and peptidyl-glutamyl peptide-hydrolyzing proteasome activity in neonatal cardiomyocytes

V. O. Kyrychenko, D. O. Pashevin, L. V. Tumanovska, V. E. Dosenko, O. O. Moibenko

Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv;
e-mail: victoria30@mail.ru

Using small interfering RNA (siRNA) transfection of neonatal cardiomyocytes to inhibit expression of nonproteolytic proteasome β7 subunit, we observed a significant decrease in β1 proteolytic subunit mRNA expression. Proteasome peptidyl-glutamyl peptide-hydrolyzing activity decreased to 28% (0.48 ± 0.2 nM AMC/min) compared to control (1.7 ± 0.5 nM AMC/min) (Р < 0.05). β5 Subunit mRNA expression decreased 21 times (Р < 0.05) with no changes in its chymotrypsin-like activity. Proteasome trypsin-like activity and activity of another proteolytic enzyme tripeptidylpeptidase II remained unchanged.