We isolated and characterized artificial transcription factors (ATFs) that functionally activate GAL1 promoter in yeast. These ATFs transformed the yeast galactose-dependent GAL1 promoter system into a galactose-independent one. The ATFs were identified by screening a combinatorial library of zinc finger-containing transcription factors for components that activated the transcription of a reporter gene under the control of a truncated GAL1 promoter from which the GAL4p-binding sites were deleted. We also showed that these ATFs activate transcription from GAL1 promoter by binding directly to specific sequence elements in the promoter. (c) 2006 Elsevier Inc. All rights reserved.