Functional studies of key regulatory genes in cell fate specification of aleurone cells with application to cereal breeding

Project summary: Recently we succeeded in identifying key regulatory genes controlling aleurone cell fate specification and development in cereal endosperm using maize as a model species. By building on these results, the proposed project aims at understanding the genetic and molecular mechanisms underlying aleurone cell fate specification in cereal endosperm with the goal of providing tools for improving the quality of cereal crops. The project will focus on two main areas; 1) Molecular characterization of endosperm and aleurone cell development in barley. Among the cereals, barley is unique in that the endosperm consistently contains three layers of aleurone cells, thus barley represents a valuable natural resource for understanding the control of aleurone cell specification. This will be carried out by isolating and characterizing the barley orthologs of the genes known to be crucial for this process in maize , phenotypic and genetic characterization of the barley mutant B5 that is affected in aleurone cell fate specification, as well as expression profiling of barley endosperm by Affymetrix-technology. 2) Analyses of the b iochemical and cell biological mechanisms of aleurone cell development using Arabidopsis as model species. This will be carried out by expressing constructs containing different domains of the DEK1 protein in transgenic Arabidopsis to