Mirko Schmitz, Eva Neugebauer, Florian Full, Kristen L. Conn
Comparative transcriptomics offers a powerful approach to elucidate host-virus interactions across related pathogens, yet systematic evaluations across species-matched cellular systems remain limited. We performed a cross-species RNA sequencing analysis of respective species' cells infected with three alphaherpesviruses-herpes simplex virus 1 (HSV-1), bovine alphaherpesvirus 1 (BHV-1), and equid alphaherpesvirus 1 (EHV-1)-to dissect conserved and virus-specific transcriptional responses. We show that certain orthologous genes and orthologous pathways are differentially regulated upon infection among the three species like pathways related to translation rRNA processing and TNF-alpha signalling. We find that the earliest sampled timepoint of infection, 2 h post infection (hpi), shows the most commonly enriched pathways among the three species compared to later timepoints. At 6 h and 9 h post infection, BHV-1- and EHV-1 infections have more in common with each other in terms of enriched pathways than with HSV-1 infections. Moreover, we provide a comprehensive analysis of temporal viral gene expression for all three herpesviruses. Together, these findings provide a comparative framework for understanding alphaherpevirus-host interactions and reveal both conserved core responses and species-specific transcriptional signatures. This work establishes a foundation for identifying broadly acting antiviral targets as well as virus-specific vulnerabilities that may inform host-directed therapies and cross-species disease management.