......................................................................................................................................... i Acknowledgements ..................................................................................................................... ii Table of Figures ......................................................................................................................... iv Background .................................................................................................................................. 1 Circoviridae .......................................................................................................................................... 1 Structure ............................................................................................................................................................ 1 Genome Organization ................................................................................................................................... 2 VP3 and Apoptosis.............................................................................................................................. 3 PCV1 VP3................................................................................................................................................ 8 Materials and Methods ........................................................................................................... 9 Results ....................................................................................................................................... 13 Discussion ................................................................................................................................ 17 Figures ....................................................................................................................................... 22 References .................................................................................................................................. 29