Repression of regulatory factor for Drosophila DNA replication-related gene promoters by zerknüllt homeodomain protein.


The expression of the chloramphenicol acetyltransferase gene under ...
The expression of the chloramphenicol acetyltransferase gene under control of the 1152-base pair 5'-flanking region (-1107 to +45 nucleotide positions with respect to the major transcription initiation site) of the Drosophila DNA polymerase alpha gene was repressed by cotransfection into Drosophila Kc cells with a zerknüllt (zen)-expressing plasmid as previously observed with the proliferating cell nuclear antigen (PCNA) gene promoter. The expression of the zen resulted in reduction of the abundance of mRNA for the transfected chloramphenicol acetyltransferase gene and also mRNAs for both DNA polymerase alpha and PCNA. Results obtained using various deletion derivatives of the promoter region and chemically synthesized oligonucleotides of the DNA replication-related element (DRE), a positive cis-acting element found in both DNA polymerase alpha and PCNA genes, revealed that the DRE sequences are responsible to repression by Zen protein. The nuclear extract of Kc cells transfected by the zen-expressing plasmid contained lesser amounts of the DRE-binding factor (DREF) than that of untransfected or mutant zen-transfected cells. These results suggest that the Zen protein represses expression of DNA replication-related genes by reducing DREF, although the detailed mechanism of the repression remains to be elucidated.




new topics/pols set partial results complete validated


No results available for this paper.

Entry validated by:

Using Polbase tables:


Tables may be sorted by clicking on any of the column titles. A second click reverses the sort order. <Ctrl> + click on the column titles to sort by more than one column (e.g. family then name).


It is also possible to filter the table by typing into the search box above the table. This will instantly hide lines from the table that do not contain your search text.