Poster: Late and Moved Abstracts

Abs # 1420: TILLING for Loss of Function Alleles in the Tomato Fruit Specific Polygalacturonase

Presenter:	McCallum, Claire M, claire@anawah.com
Authors	McCallum, Claire M (A)   Hurst, Susan R (A)   Ann, Slade J (A)   Colbert, Trent G (A)   Facciotti, Daniel  (A)   Loeffler, Dayna  (A)   Steine, Michael N (A)   McGuire, Cate  (A)   Jones, Patrick  (A)   Knauf, Vic C (A)
Affiliations:	(A): Anawah Inc.
Web Site:	http://www.anawah.com

One of the biochemical changes during tomato fruit ripening is the depolymerization and solubilization of cell wall pectin by the ripening induced enzyme polygalacturonase (PG). Solubilization of cell wall pectin contributes to rapid spoiling and hence short shelf-life in fresh market tomatoes, while in processing tomatoes, failure to inactivate PG in sauces and pastes results in an inferior product. Previous approaches to knocking out PG have been successful but involved the use of transgenic technologies. We have identified loss of function alleles in the PG gene using the TILLING reverse genetics approach. TILLING involves treating seeds with EMS to induce variation, preparing DNA from M2 plants, sample pooling, PCR amplifying the target gene, followed by single nucleotide polymorphism (SNP) analysis. By screening approximately 1300 individual M2 plants we have identified two missense alleles that are predicted to severely affect protein function. Phenotypic analysis of homozygous M3 and F2 fruit will be presented.