Studying the function and regulation of a plant member of MBF1 family. Arce D, Terrile C and Casalongué C.

ARCE D; TERRILE C; CASALONGUÉ C

USA

Congreso; Annual Meeting of Plant Biology; 2004

MBF1 is a family of transcriptional co-activators capable of interconnect regulatory proteins with TBP protein (TATA box binding protein), allowing transcriptional activation to proceed. MBF1 members from several organisms including yeast, parasites, plant and animals have been identified so far. However, functional roles of plant MBF1 remain unknown. StMBF1 (Solanum tuberosum multiprotein bridging factor 1) is able to interact in vitro with a plant Hd-Zip protein, in presence or absence of DNA. In order to get a key on the role of StMBF1 as a bridging molecule we also analysed its interaction with the potato TBP. GST-pull down assays indicated a physical interaction between both proteins, suggesting an evolutionary conservation in the mode of action of MBF1 proteins across kingdoms. To characterize the structural-functional relationships of this interaction we are testing StMBF1 mutants with different amino acid regions deleted. In addition, we examined StMBF1 expression in potato suspension cells exogenously treated with different chemical compounds (IAA, SA, JA, ABA).This approach will allow us to identify different signalling pathways potentially related with StMBF1 regulation.