A negative regulatory element in a prespore-specific promoter of Dictyostelium discoideum

We previously isolated several 'promoter-trap' transformants in which insertion of a promoterless β-galactosidase gene into the genome caused expression of β-galactosidase in specific cell types. The upstream flanking region was rescued from one transformant specifically expressing β-galactosidase in prespore cells. We sequenced the promoter of the gene that is fused in-frame with lacZ and characterised a negative element that inhibits expression in pstO cells (a subtype of prestalk cells). Gel-retardation assays show that a developmentally regulated factor(s) recognises and binds to this element. Copyright (C) 1999 Elsevier Science B.V.