Sequence and expression analysis of a cAMP‐responsive gene regulated during late development of Dictyostelium discoideum

Abstract

The 7E gene is expressed late in normal development of Dictyostelium discoideum after pseudoplasmodium formation. After disaggregation of the developing cells, transcription of this gene depends entirely on exogenous 3'5' cyclic AMP (cAMP). The 5' flanking region of the 7E gene contains two TATA box-oligo (dT) promoter motifs but analysis of 7E gene expression by primer extension shows only a single primary transcript with transcription initiating immediately after the most proximal promoter motif during development or in disaggregated cells in the presence of exogenous cAMP. Four C-rich sequences lie within 350bp upstream of the cap site, analogous to the upstream elements implicated in the cAMP regulation of several other Dictyostelium genes expressed in development.

Identification of novel elements which regulate the cell-type specificity of Dictyostelium 7E gene expression

“…The ‘full‐length’ 7E promoter fragment (− 619 to + 58) described previously (Ramji et al, 1991), directs expression of a CAT reporter gene in a temporal manner that parallels the expression of the endogenous 7E gene, both during development and in response to extracellular cAMP (McCaffery et al, manuscript submitted). To examine the cell‐type specificity of expression during development, the − 619 to + 58 promoter fragment was subcloned into the lacZ reporter vector pDdGal‐16ATG(H + ) (Stevens et al, manuscript submitted).…”