Polycomb mutant seedlings

We have identified a histone methyltransferase gene CURLY LEAF (CLF), which is required to repress a floral homeotic gene AGAMOUS (AG). CLF acts redundantly with a related gene SWINGER (SWN), so that clf swn double mutants have extreme, near lethal phenotypes in which expression of many target genes is disrupted. To understand better when and where these genes act, we propose to use a system for generating mosaic plants in which marked sectors of cells are created that gain or lose CLF (or other Pc-G) gene function in SWN+ and swn- mutant backgrounds. This will allow us to address questions such as whether the Pc-G genes are needed throughout development to silence their targets, whether they are needed once cell division has ceased, whether they can silence their targets once the targets have been activated, and whether genes that are epigenetically silenced by CLF are impervious to activating factors. Aim is to compare gene expression in wild-type and polycomb mutant seedlings. Comparison of bulked seedlings of four genotypes: wild-type (Columbia), clf-28, swn-7, clf-28 swn-7 double mutant. 8 samples were used in this experiment, 2 of each genotype. Tissue grown in tissue culture.