Abstract
The Arabidopsis CUP-SHAPED COTYLEDON genes CUC1, CUC2 and CUC3 encode transcriptional activators of the NAC family and are redundantly required for shoot meristem formation and organ separation. The cuc1 cuc2 double mutation causes severely fused cotyledons and lack of an embryonic shoot meristem. Conversely, ectopic overexpression of CUC1 or CUC2 induces ectopic shoot meristem formation on the surface of cotyledons. To identify downstream genes of CUC genes, we carried out microarray-based screenings. We first compared expression profiles in wild-type and cuc1 cuc2 embryos and obtained ten candidate genes which are significantly downregulated in cuc1 cuc2. In addition, another set of microarray experiments using 35S-CUC1 seedlings identified eleven more genes activated by CUC1 overexpression. We are now analyzing expression patterns of these candidate downstream genes in wild type embryos and the effect of CUC1 and CUC2 on them. The results from these experiments will be presented.
