Tau promoter activity in neuronally differentiated P19 cells

Tau proteins are encoded by a single gene which is regulated by a unique pr omoter. The proximal 196 base pairs of the tau 5' flanking region confers t au protein with neuronal specific expression and nerve growth factor induci bility. We tested tau promoter activity in neuronally differentiated embryo nal carcinoma cells, the P19 mouse blastoderm cell line. In these experimen ts, we examined the temporal expression pattern of the tau promoter and com pared it to other viral and cellular promoters. Tau promoter activity incre ases significantly with differentiation, specifically during neurite initia tion. In addition, tau promoter activity in neuronally differentiated P19 c ells was significantly greater than all five of the other neuronal or non n euronal promoters tested. All other promoters displayed low levels of promo ter activity throughout retinoic acid induced neuronal differentiation of P 19 cells. Taken together, our results suggest that the tau promoter is a go od choice for ectopic expression of exogenous genes in P19 cells, which ser ves as a differentiating neuronal model system. (C) 2000 Elsevier Science B .V. All rights reserved.