Silencing herpes simplex virus type 1 capsid protein encoding genes by siRNA: a promising antiviral therapeutic approach

• Published in: PloS one 2014-05, Vol.9 (5), p.e96623-e96623
• Main Authors: Jin, Fujun, Li, Shen, Zheng, Kai, Zhuo, Cuiqin, Ma, Kaiqi, Chen, Maoyun, Wang, Qiaoli, Zhang, Peizhuo, Fan, Jianglin, Ren, Zhe, Wang, Yifei
• Format: Article
• Language: English
• Subjects: Acyclovir; Animals; Antiviral agents; Biology and life sciences; Capsid protein; Capsid Proteins - genetics; Cercopithecus aethiops; Deoxyribonucleic acid; DNA; Drug resistance; Drugs; Electron microscopy; Engineering research; Gene expression; Gene Expression Regulation, Viral; Genes; Genetic engineering; Genetic Therapy; Genomes; Genomics; Health aspects; Hepatitis; Herpes simplex; Herpes Simplex - therapy; Herpes Simplex - virology; Herpes simplex virus; Herpes viruses; Herpesvirus 1, Human - genetics; Herpesvirus 1, Human - physiology; HIV; Human immunodeficiency virus; Humans; Infection; Infections; Interdisciplinary aspects; Interference; Intracellular; Kinases; Medicine; Medicine and Health Sciences; Pharmacy; Proteins; R&D; Replication; Research & development; Ribonucleic acid; RNA; RNA Interference; RNA, Small Interfering - administration & dosage; RNA, Small Interfering - genetics; RNA, Small Interfering - pharmacology; RNA-mediated interference; siRNA; Transfection; Vero Cells; Viral diseases; Viral proteins; Virions; Virology; Virus Replication; Viruses
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0096623

Herpes simplex virus type 1 (HSV-1), a member of the herpesviridae, causes a variety of human viral diseases globally. Although a series of antiviral drugs are available for the treatment of infection and suppression of dissemination, HSV-1 remains highly prevalent worldwide. Therefore, the development of novel antiviral agents with different mechanisms of action is a matter of extreme urgency. During the proliferation of HSV-1, capsid assembly is essential for viral growth, and it is highly conserved in all HSV-1 strains. In this study, small interfering RNAs (siRNAs) against the HSV-1 capsid protein were screened to explore the influence of silencing capsid expression on the replication of HSV-1. We designed and chemically synthesized siRNAs for the capsid gene and assessed their inhibitory effects on the expression of target mRNA and the total intracellular viral genome loads by quantitative real-time PCR, as well as on the replication of HSV-1 via plaque reduction assays and electron microscopy. Our results showed that siRNA was an effective approach to inhibit the expression of capsid protein encoding genes including UL18, UL19, UL26, UL26.5, UL35 and UL38 in vitro. Interference of capsid proteins VP23 (UL18) and VP5 (UL19) individually or jointly greatly affected the replication of clinically isolated acyclovir-resistant HSV-1 as well as HSV-1/F and HSV-2/333. Plaque numbers and intracellular virions were significantly reduced by simultaneous knockdown of UL18 and UL19. The total intracellular viral genome loads were also significantly decreased in the UL18 and UL19 knockdown groups compared with the viral control. In conclusion, interfering with UL18 and UL19 gene expression could inhibit HSV-1 replication efficiently in vitro. Our research offers new targets for an RNA interference-based therapeutic strategy against HSV-1.