Name: Kay Bidle

Email: bidle@marine.rutgers.edu

Author: Kay Bidle1, Assaf Vardi1, Liti Haramaty1, Ben Van Mooy2, and Helen Fredericks2

Author affiliation: 1 Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901 USA. 2 Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, USA

Abstract title: The mechanistic impact of apoptosis on algal-virus dynamics

Absstract:

Coccolithoviruses were recently shown to induce and regulate host programmed cell death (PCD) as part of their lytic pathway through late-phase induction and active recruitment of metacaspases. Emiliania huxleyi virus 86 (EhV86), the type species for Coccolithovirus, contains biosynthetic genes for cerebroside-like, glycosphingolipids that are potent inducers PCD in plants and animals, suggesting it plays an active role in eliciting PCD for successful replication. Indeed, these lipid signatures were specifically observed during viral infection and appear to be unique among marine microbes. In an attempt to put mechanistic laboratory observations in an ecological context, we analyzed natural coccolithophore populations for diagnostic hallmarks of PCD, including the induction of reactive oxygen species, metacaspases, and cerebrosides, during infection with resident viral populations. This work highlights the importance of apoptotic, molecular mechanisms to virus-host interactions and on their ecological dynamics.