Practice question

UASG contains four 17-base-pair palindromic sites for Gal4 dimer located 200-400 nucleotides upstream of GAL1/GAL10 shared TATA box. Functionally analogous to metazoan enhancer, UASG activates heterologous promoters irrespective of orientation, requires Mediator and SAGA for looped communication with basal promoter via DNA bending. When fused to CYC1 minimal promoter driving reporter, UASG confers strong galactose inducible expression, classic enhancer test. Although yeast lacks distal enhancer complexity, UASG exemplifies enhancer concept in simple eukaryote, demonstrating activator recruitment at distance stimulating transcription independently of exact distance to start site.