Melissa A. Wei with Dr. Derek J. Gingerich and Dr. Richard D. Vierstra

UW-Madison Department of Genetics

There currently exists interest in the functions of individual genes in the fully sequenced Arabidopsis thaliana genome. This study attempts to determine how mutations caused by T-DNA insertions in genes encoding E3 ubiquitin-ligase recognition factors may alter the plants’ growth and development. A total of 18 plant lines with insertions in seven different genes from two BTB gene subfamilies, (the BTB-alone group and the BTB-Ankyrin group), were genotyped, in order to identify homozygous mutants. Those containing inserts in both copies of the BTB gene were grown next to wild-type siblings, and were closely observed for aberrations in the visible morphology. These homozygous plants then selfed, and the F2 generations were observed again for more subtly different phenotypes compared to those of wild-type plants. While several homozygous individuals displayed slight morphologic differences, phenotypical abnormalities remained inconsistent within lines. Data suggests that the mutations examined are too subtle to manifest themselves under the ideal growth conditions of this study, and that additional observation could perhaps reveal abnormalities. Further experimentation, such as the application of certain stresses to identify conditional phenotypes, could better deduce the effects of mutations on the plants.