[Escherichia coli Dam methylase as a molecular tool for mapping binding sites of the yeast transcription factor Rpn4]

Rpn4p is a transcription factor responsible for coordinated regulation of proteasomal genes in Saccharomyces cerevisiae. This factor is involved directly or indirectly in regulation of comprise more than one tenth part of all yeast genome. Traditional methods are inappropriate for mapping of Rpn4p binding sites because of its extremely low concentration in the cell. We have developed the model system using Dam-methylase of E. coli which allows to detect interaction of Rpn4p with its target genes. In this system we showed that Rpn4p is recruited to proteasomal genes only through interactions with DNA.