Emiliania huxleyi is a tiny marine alga that floats freely in the ocean and makes itself a chalky outer shell from scales known as coccoliths. When conditions are right this tiny alga can grow in huge numbers (up to 10,000 in a teaspoonful of seawater) to form what is known as a 'bloom'. Unusually, the best conditions for these blooms are when concentrations of a major nutrient (phosphorus) are low. A giant virus was recently isolated that is responsible for the death of these algae. Viruses have a high phosphorus demand during infection so this group of giant viruses must have evolved a novel mechanism for infection of this globally important alga. Intriguingly, when the genome sequence of the virus was decoded, it revealed a gene known to be involved in phosphorus acquisition. The main goals of this research are to determine the function of this gene and what cellular and environmental factors regulate its operation with a view to asking if phosphorus acquisition genes are essential for a successful virus infection. Microarray technology and analysis of genomes of single infected cells will be used to investigate regulation of all genes in the virus at the same time (global expression analysis). Ultimately, this will help decipher how giant algal virus genes work together to achieve a successful infection under nutrient stress. E. huxleyi form massive blooms and they play extremely important roles in carbon sequestration and even climate regulation. All the methods outlined in this proposal will be used in the development of a new workshop in virus ecology that will eventually become part of the Bigelow summer course program aimed at senior undergraduate and graduate students. Middle school and high school audiences will be taught virus-related research through the "Cycling through the Food Web" website at Bigelow.
