Small interfering RNA targeted to stem-loop II of the 5' untranslated region effectively inhibits expression of six HCV genotypes
Authors: Robert F Garry
Srikanta Dash
Ramesh Prabhu
Journal: Virology Journal (2006)
Discipline: MICROBIOLOGY
Keywords: interferon alpha; hepatitis C virus; 5' untranslated region (UTR); internal ribosome entry site (IRES); small interfering RNA (siRNA)
Affiliations: Department of Pathology and Laboratory Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA. 

Abstract:  Background: The antiviral action of interferon alpha targets the 5' untranslated region (UTR) used by hepatitis C virus (HCV) to translate protein by an internal ribosome entry site (IRES) mechanism. Although this sequence is highly conserved among different clinical strains, approximately half of chronically infected hepatitis C patients do not respond to interferon therapy. Therefore, development of small interfering RNA (siRNA) targeted to the 5'UTR to inhibit IRES mediated translation may represent an alternative approach that could circumvent the problem of interferon resistance. Results: Four different plasmid constructs were prepared for intracellular delivery of siRNAs targeting the stem loop II-III of HCV 5' UTR. The effect of siRNA production on IRES mediated translation was investigated using chimeric clones between the gene for green fluorescence protein (GFP) and IRES sequences of six different HCV genotypes. The siRNA targeted to stem loop II effectively mediated degradation of HCV IRES mRNA and inhibited GFP expression in the case of six different HCV genotypes, where as siRNAs targeted to stem loop III did not. Furthermore, intracytoplasmic expression of siRNA into transfected Huh-7 cells efficiently degraded HCV genomic RNA and inhibited core protein expression from infectious full-length infectious clones HCV 1a and HCV 1b strains. Conclusion: These in vitro studies suggest that siRNA targeted to stem-loop II is highly effective inhibiting IRES mediated translation of the major genotypes of HCV. Stem-loop II siRNA may be a good target for developing an intracellular immunization strategy based antiviral therapy to inhibit hepatitis C virus strains that are not inhibited by interferon. 

Retracted: Yes

PubPeer comments:
 compressed image duplicated ![file] Disclaimer: These potential image duplications have been detected automatically using ImageTwin http: dx.doi.org 10.1145 3019612.3019875 Although results have been curated, the automatic algorithm may have generated false positive results and cannot take into account all scientific explanations for apparent duplications like stripped and reprobed blots, time series, serial sections and reused controls. , 
 The finding above in Comment #1 refers to Figure 4. Figure 6 also appears to show two panels that are unexpectedly similar. Marked here with red boxes. Note a little airbubble that looks like a above the 4th lane. ![file]  *This work was supported by NIH grant CA89121 (SD) and partial support from the Tulane Cancer Center.* , 
 #1 Please also note that top left and bottom center are exact duplications , 
 An illustration of the issue brought up in #3, a duplication apparently missed by ImageTwin in Comment #1, marked below in blue. ![file] Strangely enough, my copy of ImageTwin had no trouble finding the other duplication: ![file] , 
 2021 retraction. https: virologyj.biomedcentral.com articles 10.1186 s12985-021-01623-y The Editor-in-Chief has retracted this article. Concerns were raised regarding a number of figures, specifically: Figure 4: the pCVH77C +siRNA74 panel appears to overlap with the pCVJ4L6S +siRNA74 panel Figure 4: the pCVH77C Full-length HCV panel appears to be identical with the pM.O.9.6.-T7 +EBNA1 panel Figure 6: the bottom center and bottom right panels appear to be identical The article also shows significant overlap with a previously published article [1]. The Editor-in-Chief therefore no longer has full confidence in the reliability of some data reported in the article. Robert F. Garry and Srikanta Dash agree to this retraction. The editor was not able to obtain a current email address for Ramesh Prabhu. Reference 1. Prabhu R, Vittal P, Yin Q, Flemington E, Garry R, Robichaux WH, Dash S. Small interfering RNA effectively inhibits protein expression and negative strand RNA synthesis from a full-length hepatitis C virus clone. J Med Virol. 2005;76:511u20139. https: doi.org 10.1002 jmv.20391. ,