000063302 001__ 63302 000063302 005__ 20171129112117.0 000063302 0247_ $$2doi$$a10.1371/journal.pone.0069773 000063302 0248_ $$2sideral$$a82460 000063302 037__ $$aART-2013-82460 000063302 041__ $$aeng 000063302 100__ $$0(orcid)0000-0001-5664-1729$$aAbian, O.$$uUniversidad de Zaragoza 000063302 245__ $$aAllosteric Inhibitors of the NS3 Protease from the Hepatitis C Virus 000063302 260__ $$c2013 000063302 5060_ $$aAccess copy available to the general public$$fUnrestricted 000063302 5203_ $$aThe nonstructural protein 3 (NS3) from the hepatitis C virus processes the non-structural region of the viral precursor polyprotein in infected hepatic cells. The NS3 protease activity has been considered a target for drug development since its identification two decades ago. Although specific inhibitors have been approved for clinical therapy very recently, resistance-associated mutations have already been reported for those drugs, compromising their long-term efficacy. Therefore, there is an urgent need for new anti-HCV agents with low susceptibility to resistance-associated mutations. Regarding NS3 protease, two strategies have been followed: competitive inhibitors blocking the active site and allosteric inhibitors blocking the binding of the accessory viral protein NS4A. In this work we exploit the intrinsic Zn+2-regulated plasticity of the protease to identify a new type of allosteric inhibitors. In the absence of Zn+2, the NS3 protease adopts a partially-folded inactive conformation. We found ligands binding to the Zn+2-free NS3 protease, trap the inactive protein, and block the viral life cycle. The efficacy of these compounds has been confirmed in replicon cell assays. Importantly, direct calorimetric assays reveal a low impact of known resistance-associated mutations, and enzymatic assays provide a direct evidence of their inhibitory activity. They constitute new low molecular-weight scaffolds for further optimization and provide several advantages: 1) new inhibition mechanism simultaneously blocking substrate and cofactor interactions in a non-competitive fashion, appropriate for combination therapy; 2) low impact of known resistance-associated mutations; 3) inhibition of NS4A binding, thus blocking its several effects on NS3 protease. 000063302 536__ $$9info:eu-repo/grantAgreement/ES/DGA/B01$$9info:eu-repo/grantAgreement/ES/DGA/B89$$9info:eu-repo/grantAgreement/ES/DGA/PI044-09$$9info:eu-repo/grantAgreement/ES/FIS/PI10-00186$$9info:eu-repo/grantAgreement/ES/MICINN/BFU2010-16297$$9info:eu-repo/grantAgreement/ES/MICINN/BFU2010-19451$$9info:eu-repo/grantAgreement/ES/MICINN/PTA2009-2341-I$$9info:eu-repo/grantAgreement/ES/UZ/UZ2009-BIO-05 000063302 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/ 000063302 590__ $$a3.534$$b2013 000063302 591__ $$aMULTIDISCIPLINARY SCIENCES$$b8 / 56 = 0.143$$c2013$$dQ1$$eT1 000063302 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000063302 700__ $$0(orcid)0000-0002-1232-6310$$aVega, S. 000063302 700__ $$0(orcid)0000-0002-2879-9200$$aSancho, J.$$uUniversidad de Zaragoza 000063302 700__ $$0(orcid)0000-0001-5702-4538$$aVelazquez-Campoy, A.$$uUniversidad de Zaragoza 000063302 7102_ $$11002$$2060$$aUniversidad de Zaragoza$$bDepartamento de Bioquímica y Biología Molecular y Celular$$cBioquímica y Biología Molecular 000063302 773__ $$g8, 7 (2013), e69773 [10 pp]$$pPLoS One$$tPLoS One$$x1932-6203 000063302 8564_ $$s356256$$uhttps://zaguan.unizar.es/record/63302/files/texto_completo.pdf$$yVersión publicada 000063302 8564_ $$s126536$$uhttps://zaguan.unizar.es/record/63302/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000063302 909CO $$ooai:zaguan.unizar.es:63302$$particulos$$pdriver 000063302 951__ $$a2017-11-28-12:46:09 000063302 980__ $$aARTICLE