InterDiVE · Host-virus interactions in marine diatoms across environmental and ecophysiological gradients

Diatoms shape the global carbon cycle, contributing ~20% of primary production on the planet and nearly half of the carbon sequestration in the ocean. Marine viruses transform ecological, evolutionary and biogeochemical processes, yet the impact of viral infection on diatoms remains a fundamental gap in our understanding of microbial dynamics in the ocean. The landmark discovery of diatom-infecting viruses, together with advances in high throughput sequencing and imaging technologies now enable the exploration of diatom host-virus interactions at unprecedented resolution. We know very little about when, where and how viruses impact diatom populations, despite the potential for viral infection to radically alter diatom ecology and diatom-mediated biogeochemistry. Proposed work seeks to elucidate how virus infection of diatoms manifests along environmental and ecophysiological gradients in the ocean. Our team will pursue three complementary aims: (1) Characterize the impacts of environmental stress on virus production and virus-mediated mortality in diatoms; (2) Determine the ecophysiological frameworks that drive diatom host-virus dynamics; (3) Capture and contextualize diverse host-virus interactions throughout a diatom bloom. Using a multi-tiered and interdisciplinary approach that draws upon molecular biology, biogeochemistry and biological oceanography, we will interrogate diatom host-virus interactions across environmental gradients in model systems and natural communities. Amidst the urgency to decipher how ocean processes respond to global climate change, InterDiVE will provide invaluable ecological, ecophysiological, and molecular insight into how environmental conditions regulate diatom host-virus interactions, advancing our understanding of the microscale dynamics that underpin primary production and biogeochemical cycling in the global ocean.