Bidirectional activity and orientation-dependent specificity of the rat aldolase C promoter in transgenic mice

We previously reported that the rat aldolase C 115 bp promoter is sufficien t to ensure the brain specific expression of the chloramphenicol acetyltran sferase reporter gene in transgenic mice. We identify in a further reduced 84 bp promoter several putative binding sites for the transcriptional facto rs Sp1, USP, AP1, and AP2, Deletion or mutation of these partially overlapp ing binding sites results in inactivation of the cognate transgenes. Moreov er, we show that the 115 bp sequence is able to direct bidirectional transc ription in vivo but, surprisingly, transcriptional activity in the opposite direction is no more brain specific. (C) 2001 Federation of European Bioch emical Societies. published by Elsevier Science B.V. All rights reserved.