21 Jul 2025

Abstract: Herpesviruses are characterized by highly GC-rich genomes and several lines of evidence suggest the formation of G-quadruplexes (G4s) within these viral DNA sequences. Kaposis’s sarcoma associated herpesvirus (KSHV), the etiological agent of multiple lymphoproliferative diseases, contains an extensive non-coding repetitive region named terminal repeats (TRs) with a GC content higher than 80%. TRs are crucial for KSHV latency, mediating efficient latent viral genome replication and segregation during host cell division through binding of the essential latency-associated nuclear antigen (LANA). TRs have been previously proposed to form G4s. However, the function of these difficult-to-replicate regions within the genome of KSHV and how they are processed by the eukaryotic host replication machinery during viral latency remain unknown.

We exploit in vitro replication in Xenopus laevis egg extracts combined with work in infected human lymphoblasts as complementary es to dissect the contribution of DNA secondary structures and of LANA to the replication of TRs. By using mass-spectrometry based approaches, we also identify eukaryotic proteins and pathways recruited to the TRs and we dissect their contribution during DNA replication.

Biography: Irene Gallina is a molecular biologist with a longstanding interest in the mechanisms of DNA replication and repair. After earning her PhD in at the University of Copenhagen, she conducted a postdoctoral training at the Novo Nordisk Foundation Center for Protein Research, investigating DNA replication dependent DNA repair in Xenopus laevis egg extracts. She is now Assistant Professor at the Department of Molecular Medicine at the University of Padova, where she is coordinating a small research group focused on exploiting the in vitro system from egg extracts to dissect the molecular basis of herpesvirus replication.
Download poster