1. Targeting genomic SARS-CoV-2 RNA with siRNAs allows efficient inhibition of viral replication and spread
- Author
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Shubhankar Ambike, Cho-Chin Cheng, Martin Feuerherd, Stoyan Velkov, Domizia Baldassi, Suliman Qadir Afridi, Diana Porras-Gonzalez, Xin Wei, Philipp Hagen, Nikolaus Kneidinger, Mircea Gabriel Stoleriu, Vincent Grass, Gerald Burgstaller, Andreas Pichlmair, Olivia M Merkel, Chunkyu Ko, and Thomas Michler more...
- Subjects
Cell Survival ,AcademicSubjects/SCI00010 ,viruses ,Oligonucleotides ,Virus Replication ,Antiviral Agents ,03 medical and health sciences ,Open Reading Frames ,0302 clinical medicine ,Databases, Genetic ,Genetics ,Animals ,Humans ,RNA, Small Interfering ,3' Untranslated Regions ,Lung ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,SARS-CoV-2 ,COVID-19 ,3. Good health ,COVID-19 Drug Treatment ,HEK293 Cells ,030220 oncology & carcinogenesis ,Nucleic Acid Conformation ,RNA, Viral - Abstract
A promising approach to tackle the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) could be small interfering (si)RNAs. So far it is unclear, which viral replication steps can be efficiently inhibited with siRNAs. Here, we report that siRNAs can target genomic RNA (gRNA) of SARS-CoV-2 after cell entry, and thereby terminate replication before start of transcription and prevent virus-induced cell death. Coronaviruses replicate via negative sense RNA intermediates using a unique discontinuous transcription process. As a result, each viral RNA contains identical sequences at the 5′ and 3′ end. Surprisingly, siRNAs were not active against intermediate negative sense transcripts. Targeting common sequences shared by all viral transcripts allowed simultaneous suppression of gRNA and subgenomic (sg)RNAs by a single siRNA. The most effective suppression of viral replication and spread, however, was achieved by siRNAs that targeted open reading frame 1 (ORF1) which only exists in gRNA. In contrast, siRNAs that targeted the common regions of transcripts were outcompeted by the highly abundant sgRNAs leading to an impaired antiviral efficacy. Verifying the translational relevance of these findings, we show that a chemically modified siRNA that targets a highly conserved region of ORF1, inhibited SARS-CoV-2 replication ex vivo in explants of the human lung. Our work encourages the development of siRNA-based therapies for COVID-19 and suggests that early therapy start, or prophylactic application, together with specifically targeting gRNA, might be key for high antiviral efficacy., Graphical Abstract Graphical AbstractExclusive targeting of SARS-CoV-2 genomic RNA enables most efficient suppression of viral replication and virus-induced cell death. more...
- Published
- 2021