Gene Structure and Function
Locascio, Antonella , Vannozzi, Alessandro , Amasino, Richard , Lucchin, Margherita , Varotto, Serena .
Analysis of flowering mediated by vernalization in Cichorium intybus L.
Since proper timing of flowering is critical for the survival of plant species, plant have evolved a complex genetic network to regulate phase transition in response to endogenous signals and environmental cues. In winter annuals ecotypes of Arabidopsis, a flowering repressor, FLOWERING LOCUS C (FLC), is expressed at levels that inhibit flowering in the first growing season. FLC expression is enhanced by FRIGIDA (FRI), then it repress the genes referred to as Floral Pathways Integrators. Vernalization promotes flowering by FLC repression inducing epigenetically stable modifications. Comparative genetic approaches show that flowering time genes are conserved between Arabidopsis and a large range of crop species, including legumes and cereals. By contrast, the vernalization pathway seems to be only partially conserved, since FLC and FRI were not characterized in dicots other than Brassicaceae. Wild chicory (Cichorium intybus L.) is a biennial species which requires vernalization to flower. In Italy different types of chicory have been selected by farmers as leafy vegetable. These types show quite different classes of precocity in relation to flowering. We are investigating the molecular basis that regulate flowering in chicory by vernalization, to verify whether such mechanism is the same that controls flowering in Arabidopsis, and, finally, to address the diversity of the classes of precocity to one of the cases known for this model plant. We isolated FLC homologues from chicory and characterized their expression in plant tissues. We studied the pattern of cytosine methylation in chicory genomic DNA in response to vernalization. In addition, a vernalization-mediated decrease of FLC transcript has been determinate and related with changes in SAM morphology. Preliminary data indicate that arabidopsis and chicory share homologies in regulating FLC expression in the vernalization response. Further analysis will be conducted to define if the machinery in FLC regulation is shared between the two species.
Log in to add this item to your schedule
1 - University of Padova, Environmental Agronomy and Crop Production, viale dell'Universitą 16, Legnaro, Padova, Italy, 35020, Italy
2 - University of Wisconsin, Biochemistry, 433 Babcock drive, Madison, Wisconsin, 53706, USA
Presentation Type: Poster:Posters for Topics
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM