Hyperthermophilic archaeal viruses, along with exceptional morphological and genomic properties, have unique, still unexplored ways of interaction with their hosts. One example is provided by a unque egress mechanism of the rudivirus SIRV2, which involves formation of hexagonal virus-induced pyramids, VAPs, on the host cell surface, which eventually open out, thus creating large apertures through which virions escape the cell. The SIRV2-encoded 10-kDa protein P98 is the sole component of the VAP and self-sufficient for the assembly into 7-fold pyramids in any kind biological membranes from all three domains of life.
For studies on molecular details of virus-host interplay in Archae we have selected three model viruses – the rod-shaped rudivirus SIRV2, the spindle-shaped fusellovirus SSV1 and the bacilliform clavavirus APBV1, which collectively provide insights into the diversity of basic strategies employed by archaeal viruses in extreme geothermal habitats.
Molecular mechanisms of all virus-related processes are addressed, starting from receptor recognition and entry into the host cell, to transcription and replication of viral genomes, and virion assembly and their targeting to the sites of exit. In these studies, we will exploit a combination of structural, biochemical, microbiological and genetic approaches.