Allelic polymorphism of genes encoding catalytic immunoproteasome subunits and its functional meaning

: Proteasomal activity in isolated monocytes from subjects with different variants of large multifunctional proteases genes -LMP2 (Arg60-->His allelic polymorphism) and LMP7 (Lys145-->Gln allelic polymorphism) was determined. Trypsin-like activity of proteasome was 1.6-times (P = 0.19) higher at Arg/Arg genotype comparing to His/His genotype, and 2-fold lower than at Arg/His genotype. The highest chymotrypsin-like activity of proteasome was observed in heterozygotes (on 29.7% higher comparing to Arg/Arg genotype, P = 0.43) and lowest in homozygotes His/His (on 29.7% less comparing to Arg/Arg genotype, P = 0.40). Level of RNA expression in isolated monocytes detetermined by use of RT-PCR did not differed significantly in subjects with different genotypes. Data obtained indicate that LMP2 allelic polymorphism impact peptidase activity of immunoproteasome.