Protein p6 from HIV-1 gag open reading frame is reported to affect both the final phase of assembly of the viral particle and the early stage of the gag polyprotein maturation in vitro. Two separate hypotheses have been proposed, on only one of these reported effects. We think that both observations may be eventually explained if p6 protein strongly inhibits the HIV-1 proteinase. Protein p6 was synthesised by solid-phase peptide synthesis. Several methods of folding the p6 protein were tested, each resulting in the random structure according to both CD and 1D proton NMR spectra. A uniformly high exposure of NH protons to the solution was confirmed by temperature-dependent NMR spectra and isotope exchange experiments. Thus the p6 protein does not have any rigid conformation in solution. A rigid structure is not formed after further cleavage by HIV-1 proteinase as neither the protein nor its fragments are cleaved by this proteinase. In addition, the p6 protein itself does not act as inhibitor of HIV-1 proteinase. This excludes a direct role of p6 protein and supports the hypothesis that p6 is involved in forming the appropriate structure of gag polyprotein precursor. The role of slowly cleaved tight gag-proteinase in the final stage of maturation may be to slow down maturation of the precursor polyproteins prior to their transport to final location in the membrane.

• MeSH
• cirkulární dichroismus MeSH
• DNA vazebné proteiny chemická syntéza   chemie   metabolismus   MeSH
• HIV-1 enzymologie   genetika   MeSH
• inhibitory HIV-proteasy chemie   metabolismus   MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární sekvence - údaje MeSH
• otevřené čtecí rámce MeSH
• sekundární struktura proteinů MeSH
• sekvence aminokyselin MeSH
• software MeSH
• virové proteiny chemická syntéza   chemie   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA vazebné proteiny MeSH
• inhibitory HIV-proteasy MeSH
• viral protein p6 MeSH Prohlížeč
• virové proteiny MeSH