[Artifitial increase of HIV-1 reverse transcriptase turnover through proteasome pathway].
Proteasome plays a key role in antigen presentation through MHC class I pathway. Thus, approaches are actively developed to increase proteasome targeting of DNA-vaccine encoded proteins. Gene of reverse transcriptase of HIV-1 is used in DNA-vaccines. It was shown, that revertase degraded in cells slowly (half-life is 18-20 h). Revertase content increased in presence of proteasome inhibitors MG132 and epoxomicin indicated that it degraded by proteasome. Level of protein was 2 fold higher after treatment with MG132 then after epoxomicin treatment. Since epoxomicin is more specific proteasome inhibitor it indicated that other cellular proteases can take part in revertase degradation. With the aim to increase affinity and degradation rate by proteasome of revertase we have to add strong degradation signal. Ornithine decarboxylase contains this kind of signals, it's unique properties are fast degradation by proteasome in ubiquitin-independent manner. As result fusion protein of revertase and ornithine decarboxylase was created. Half-life of fusion protein was 6 time less than revertase (3 h). Degradation of fusion protein was blocked by proteasome inhibitors 10 times stronger than revertase. Thus, degradation by proteasome pathway of reverse transcriptase was enhanced by fusion with ornithine decarboxylase. Performance of this fusion could improve presentation of revertase in DNA-vaccine.
Starodubova
E S
ES
Isaguliants
M G
MG
Karpov
V L
VL
D000818:Animals; D002478:Cells, Cultured; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D054303:HIV Reverse Transcriptase / Q000235:genetics / Q000378:metabolism*; D006207:Half-Life; D006801:Humans; D007976:Leupeptins / Q000494:pharmacology; D051379:Mice; D009842:Oligopeptides / Q000494:pharmacology; D009955:Ornithine Decarboxylase / Q000235:genetics / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D061988:Proteasome Inhibitors; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D019444:Vaccines, DNA / Q000378:metabolism
D015853:Cysteine Proteinase Inhibitors; D007976:Leupeptins; D009842:Oligopeptides; D061988:Proteasome Inhibitors; D011993:Recombinant Fusion Proteins; D019444:Vaccines, DNA; D054303:HIV Reverse Transcriptase; D046988:Proteasome Endopeptidase Complex; D009955:Ornithine Decarboxylase; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde; C078846:epoxomicin