Homopolymer mutational hot spots mediate herpes simplex virus resistance to acyclovir
| Autor: | K Schubert, Joe Sasadeusz, S. Safrin, Peter K. Cheung, Stephen L. Sacks, Frank Tufaro, M M Hubinette |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Simplexvirus
food.ingredient Immunology Blotting Western Drug Resistance Acyclovir Biology medicine.disease_cause Microbiology Antiviral Agents Thymidine Kinase Frameshift mutation food Western blot HSV-Tk Gene Virology medicine Humans Mutation medicine.diagnostic_test Phenotype Molecular biology Herpes simplex virus Thymidine kinase Insect Science Research Article |
| Zdroj: | Journal of virology. 71(5) |
| ISSN: | 0022-538X |
| Popis: | In the majority of cases, the mechanism underlying the resistance to acyclovir (ACV) of herpes simplex viruses (HSVs) is thymidine kinase (TK) deficiency. Plaque isolates from eight ACV-resistant (ACVr) clinical isolates from AIDS patients, of which five reactivated, were sequenced to determine the genetic lesion within the tk gene conferring resistance and whether this may have correlated with reactivation potential. Mutations were clustered within two homopolymer nucleotide stretches. Three plaque isolates (1737-14, 90-150-3, and 89-650-5) had insertion mutations within a stretch of 7 guanosines, while two isolates (89-063-1 and 89-353-1) had frameshift mutations within a stretch of 6 cytosines (a deletion and an insertion, respectively). Mutations resulted in premature termination codons, and the predicted 28- and 32-kDa truncated TK products were detected by Western blot analysis of virus-infected cell extracts. The repair of one homopolymer frameshift mutation (in isolate 1737-14) restored TK activity, demonstrating that this mutation is the basis of TK deficiency. Of the five reactivated isolates, four were TK deficient and contained frameshift mutations while the fifth retained TK activity because of its altered-TK or Pol- phenotype. These data demonstrate that the majority of ACVr clinical isolates contain frameshift mutations within two long homopolymer nucleotide stretches which function as hot spots within the HSV tk gene and produce nonfunctional, truncated TK proteins. |
| Databáze: | OpenAIRE |
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