UAS sequences regulate expression of a bicistronic transcript that encodes two open reading frames separated by a 2A linker (this results in separate translation of each protein). The first ORF comprises Hsap\H2B tagged with RFP(Unk). The second ORF comprises Rnor\Hmgb1 tagged with GFP (this protein can be used as a marker for necrosis: nuclear localization of the protein is lost in necrotic cells).