An intronic domain within the rat preprotachykinin-A gene containing a CCCT repetitive motif acts as an enhancer in differentiating embryonic stem cells

Previous attempts by several groups to clone fragments containing intron 2 of the rat preprotachykinin-A gene have generated deletions of various size s. We have determined that these deletions occur within a specific region o f the intron spanning a CCCT tandem repeat domain. We show that this intron ic domain is able to support reporter gene expression in mouse embryonic st em (ES) cells that have been induced to differentiate but not in undifferen tiated ES cells. No significant expression was observed in the HeLa clonal cell line. This demonstrates that this intron 2 domain is a highly restrict ive enhancer and may be associated with differentiation. (C) 1999 Published by Elsevier Science Ireland Ltd. All rights reserved.