RESUMO

Mutations in the connection subdomain (CN) and RNase H domain (RH) of HIV-1 reverse transcriptase (RT) from subtype B-infected patients enhance nucleoside and nonnucleoside RT inhibitor (NRTI and NNRTI) resistance by affecting the balance between polymerization and RNase H activity. To determine whether CN mutations in subtype C influence drug sensitivity, single genome sequencing was performed on Brazilian subtype C-infected patients failing RTI therapy. CN mutations identified were similar to subtype B, including A376S, A400T, Q334D, G335D, N348I, and A371V, and increased AZT resistance in the presence of thymidine analog mutations. CN mutations also enhanced NNRTI resistance in the presence of classical NNRTI mutations: etravirine resistance was enhanced 6- to 11-fold in the presence of L100I/K103N/Y181C. These results indicate that selection of CN mutations in treatment-experienced patients also occurs in subtype-C-infected patients and are likely to provide valuable information in predicting clinical RTI resistance.

Assuntos

Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , Mutação , Inibidores da Transcriptase Reversa/farmacologia , Sequência de Aminoácidos , Brasil , Linhagem Celular , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/genética , Humanos , Dados de Sequência Molecular , Nitrilas , Estrutura Terciária de Proteína/genética , Piridazinas/farmacologia , Pirimidinas , Zidovudina/farmacologia