THE CANADIAN POTATO GENOME PROJECT

¹ Genome Atlantic, 921 College Hill Road, Fredericton, New Brunswick, E3B 6Z9, Canada

² AAFC, Potato Research Centre, 850 Lincoln Road, Fredericton, New Brunswick, E3B 9H8, Canada

³ Nova Scotia Agricultural College, Department of Plant and Animal Sciences, PO Box 550, Truro, Nova Scotia, B2N 5E3, Canada

⁴ Carleton University, Department of Biology, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6,Canada

The Canadian Potato Genome Project (CPGP) is focused on an analysis of the genes that govern the characteristics of the potato tuber, as well as the genes associated with responses to specified pathogens and certain environmental cues. To carry this out, strategic resources being developed include the generation of 5' and 3' ESTs and the production of activation tagged mutants. Over 40,000 clones from a variety of regular and normalized cDNA libraries have been sequenced so far, yielding tentative consensus (TC) sequences and singletons representing several thousand unigenes. While numerous TC and singleton sequences show identity to known Solanaceae sequences, many novel TC and singleton sequences have been identified. The identity of the top TC sequences vary between libraries, but functional annotations reveal that the predominant biological processes represented in each library are metabolism, cell growth and cell maintenance. Gene discovery and inferred functionality can be carried out via EST sequence generation, as well via the screening of phenotypic mutant lines. However, the tetraploid nature of the potato genome makes it unrealistic to produce mutants by knockout technology, and as a result very few mutants are available in potato. But activation tagging, using multimerized enhancers from the cauliflower mosaic virus 35S promoter to activate expression of a neighbouring gene, results in a dominant gain-of-function phenotype that should be detectable in complex genomes. We are producing up to 20,000 activation tagged lines of potato, with future screening for obvious changes in plant morphology and traits related to tuber quality and tuber health.