Transcription activator that binds to 5'-TATCCA-3' elements in gene promoters. Derepresses weakly the sugar-repressed transcription of promoters containing SRS. Contributes to the sugar-repressed transcription of promoters containing 5'-TATCCA-3' elements. Expressed mainly in roots, leaves, and senescent leaves at similar levels. Induced by sucrose. Slightly repressed by gibberellic acid (GA).