RRC ID 29020
Author Fukuzawa M, Williams JG.
Title Analysis of the promoter of the cudA gene reveals novel mechanisms of Dictyostelium cell type differentiation.
Journal Development
Abstract The cudA gene encodes a nuclear protein that is essential for normal multicellular development. At the slug stage cudA is expressed in the prespore cells and in a sub-region of the prestalk zone. We show that cap site distal promoter sequences direct cudA expression in prespore cells, while proximal sequences direct expression in the prestalk sub-region. The promoter domain that directs prespore-specific transcription consists of a positively acting region, that has the potential to direct expression in all cells within the slug, and a negatively acting region that prevents expression in the prestalk cells. Dd-STATa is the STAT protein that regulates commitment to stalk cell gene expression, where it is known to function as a transcriptional repressor. We show that Dd-STATa binds in vitro to the positively acting part of the prespore domain of the cudA promoter. However, Dd-STATa cannot be utilised for this purpose in vivo, because analysis of a Dd-STATa null mutant strain shows that Dd-STATa is not necessary for cudA transcription in prespore cells. In contrast, the part of the cudA promoter that directs prestalk-specific expression contains a binding site for Dd-STATa that is essential for its biological activity. Dd-STATa appears therefore to serve as a direct activator of cudA transcription in prestalk cells, while a protein with a DNA binding specificity highly related to that of Dd-STATa is utilised to activate cudA transcription in prespore cells.
Volume 127(12)
Pages 2705-13
Published 2000-6-1
PMID 10821768
MeSH Actins / genetics Animals Base Sequence Cell Differentiation Cloning, Molecular Dictyostelium / cytology* Dictyostelium / genetics* Dictyostelium / physiology Gene Expression Regulation Molecular Sequence Data Mutagenesis Nuclear Proteins / genetics* Nuclear Proteins / metabolism Promoter Regions, Genetic* Protozoan Proteins / genetics Recombinant Proteins / metabolism Ribonucleotide Reductases / genetics Sequence Deletion Spores Transcription, Genetic
IF 5.611
Times Cited 44
Cellular slime molds S90304