The PEBP family of genes in chicory and their role in flowering time and root development

English. The PHOSPHATIDYLETHANOLAMINE-BINDING PROTEIN (PEBP) gene family is present in all eukaryotic kingdoms. In plants, three separate subfamilies have been identified, all of which have diversified functions. In Arabidopsis thaliana, the PEBP family members have been assigned roles as promoting or repressing flowering, controlling inflorescence meristem determinacy and axillary bud growth. Members of the PEBP family have also been identified to play a role in tuber initiation in potato but not much is known about the role of PEBPs in root development, especially for species that form storage roots. Root chicory (Cichorium intybus var. sativum) is a biennial crop used for nutrition, animal feed and as coffee substitute and is one of the most important sources of inulin, a type of polysaccharides that is gaining great importance in the food and medical industry. Chicory root extracts have been found to have hepatoprotective, anti-bacterial, anti- inflammatory, anti-microbial, nematicidal and anti-cancer effects. With the use of bioinformatic tools, the sequences of chicory FLOWERING LOCUS T (CiFT) and TERMINAL FLOWER1 (CiTFL1-1 to 4) like genes were identified and the coding sequences were overexpressed in null A. thaliana mutants (ft-10 or tfl1). Independent transgenic lines for each gene were phenotyped for flowering time and root development. In addition, the expression pattern of these genes was analyzed in chicory in various tissues during early stages of plant development and initiation of root storage. Transformation of chicory is being performed using an Agrobacterium rhizogenes in vitro transformation protocol. The results of this project will help us elucidate the role for the PEBPs in flowering and root development in chicory.

Rootsctock