Functional analysis of NF-Y transcription factors in Arabidopsis

In yeast and mammals, the CCAAT box, one of the most promoter ubiquitous elements, is recognized by NF-Y, a trimer composed by NF-YA, NF-YB and NF-YC, all required for DNA-binding and encoded by single copy genes. In Arabidopsis thaliana 29 NF-Y genes have been cloned: 10 NF-YAs, 10 NF-YBs, 9 NF-Ycs. The aim of this Ph.D project has been the functional characterisation of some members of this gene family. To determine the function of these transcription factors, various approaches have been undertaken such as analysis of expression pattern, mutant and double mutants selection, production of transgenic plants in which the selected NF-Y gene is silenced by RNA interferences technics or ectopically expressed. Moreover, interactions among NF-Y subunits have been studied. Two-Hybrid analysis indicates that all B subunit are able to interact with C subunit tested and the colorimetric assay indicates that some interaction are favourite in comparison to others. Some of these data have been confirmed by biochemical assays.