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bioRxiv · 10.1101/2020.12.23.424160

Herpes Simplex Virus Type 1 Co-Infection Leads to the Formation of Rolling Circle Amplification-Like Adeno-Associated Virus DNA Replication Products

Meier, A. F.·Tobler, K.·Leisi, R.·Lkharrazi, A.·Ros, C.·Fraefel, C.
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Abstract

Adeno-associated virus (AAV) genome replication only occurs in the presence of a co-infecting helper virus such as adenovirus type 5 (AdV5) or herpes simplex virus type 1 (HSV-1). AdV5-supported replication of the AAV genome has been described to occur in a strand-displacement rolling hairpin replication (RHR) mechanism initiated at the AAV 3 inverted terminal repeat (ITR) end. It has been assumed that the same mechanism applies to HSV-1-supported AAV genome replication. Using nanopore sequencing as a novel, high-throughput approach to study viral genome replication we demonstrate the formation of double-stranded head-to-tail concatemers of AAV genomes in the presence of HSV-1, thus providing evidence for an unequivocal rolling circle replication (RCR) mechanism. This stands in contrast to the textbook model of AAV genome replication when HSV-1 is the helper virus. SIGNIFICANCEEfficient adeno-associated virus (AAV) replication requires the presence of helper factors, which can be provided by co-infecting helper viruses such as adenoviruses or herpesviruses. AAV replication has been described to occur as a rolling hairpin replication mechanism. However, we show that during a herpes simplex virus type 1 (HSV-1) supported replication, AAV rolling circle-like replication intermediates are formed. Thus, this study stands in contrast to the textbook model of AAV genome replication. Additionally, we introduce nanopore sequencing as a novel, high-throughput approach to study viral genome replication in unprecedented detail.

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Meier, A. F., Tobler, K., Leisi, R., Lkharrazi, A., Ros, C., Fraefel, C.. 2020-12-23. Herpes Simplex Virus Type 1 Co-Infection Leads to the Formation of Rolling Circle Amplification-Like Adeno-Associated Virus DNA Replication Products. https://doi.org/10.1101/2020.12.23.424160

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