Expression and characterization of a potato transcriptional coactivator (StMBF1) under different environmental conditions

ARCE D; TONÓN C; DALEO G; CASALONGUÉ C

Bariloche, Rio Negro

Congreso; Reunión Anual SAIB; 2003

SAIB

MBF is an evolutionary conserved transcriptional coactivator that connects a regulatory factor and TATA element-binding protein (TBP). We have reported the identification of a Solanum tuberosum transcriptional coactivator, named StMBF1,which is up-regulated during Fusarium eumartii attack as well as wounding in potato tubers. StMBF1 is phosphorylated under in vivo and in vitro experimental conditions after treatment of potato cells with hyphal cell wall components. In addition, StMBF1 interacts in vitro with plant transcription factors of the Hd-Zip family. Since some members of Hd-Zip proteins are inducible by plant growth regulators and stress conditions, we attempted to know the StMBF1 expression pattern in potato suspension cells under different physiological conditions. The results indicated that StMBF1 accumulates by ABA, SA and heat shock treatments. In order to evaluate the putative interaction between StMBF1 and TBP proteins we expressed the potato TBP protein in E. coli. Proteinprotein interaction is currently being tested by GST-pull down assays. Our results suggest that StMBF1 may posses a versatile regulation and it would mediate the coupling of different environmental signals within developmental program. Supported by IFS, CONICET, F. Antorchas, ANPCyT, UNMDP