CSB Seminar Series – Kathryn Rozen-Gagnon, PhD – Department of Molecular Genetics, University of Toronto

CSB Departmental Seminar

Kathryn Rozen-Gagnon, PhD

Department of Molecular Genetics, University of Toronto

TITLE: Arbovirus biology through the lens of miRNA interactions

ABSTRACT: Arthropod-borne viruses (arboviruses) are major human pathogens, infecting ~400 million people yearly. Nearly all pathogenic arboviruses have short RNA genomes encoding ~10 genes. This infectious RNA must infect mosquitoes to successfully infect humans. Intriguingly, while humans become sick but usually recover, mosquitoes remain infected for life, happily feeding and infecting new hosts. We still lack a thorough understanding of how arbovirus RNA genomes succeed in these extremely divergent organisms. Inside a human or mosquito cell, the viral RNA will encounter radically different host RNAs and RNA-processing systems (RNA networks). Myriad interactions can occur between arbovirus RNA and cellular RNA networks, to either promote or hinder the viral life cycle. Of major interest, cellular microRNA (miRNA) networks modulate gene expression in both organisms and likely interact with arboviruses. Indeed, we know that several RNA viruses rely on miRNAs to successfully infect mammalian cells or evade immune detection. Yet, how and why mosquito-borne viruses interact with miRNA networks remains largely unexplored, particularly in mosquitoes, where we lack many research tools available in human cells. Our recent advances now allow transcriptome-wide mapping of mosquito miRNA interactions. These methods were used to uncover novel miRNA interactions for two emerging arboviruses: chikungunya and Zika viruses. We found these interactions benefited both viruses, expanding the list of arboviruses that engage host miRNAs. Further, because miRNAs modulate host gene expression programs, these interactions shed new light on cellular processes important for arbovirus infection and pathogenesis in different cell types and organisms.

HOST: Arneet Saltzman

LOCATION: Cell and Systems Biology, 25 Harbord Street, Suite 432