In molecular biology, a downstream promoter element (DPE) is a

core promoter In genetics, a promoter is a sequence of DNA to which proteins bind to initiate transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein (mRNA), or can have a function in and of i ...

element. Like all core promoters, the DPE plays an important role in the initiation of gene transcription by RNA polymerase II. The DPE was first described by T. W. Burke and James T. Kadonaga in '' Drosophila melanogaster'' at the University of California, San Diego in 1996. It is also present in other species including humans, but not '' Saccharomyces cerevisiae''. Together with the initiator motif (Inr), another core promoter element, the DPE is recognized by the transcription factor II D (TFIID) subunits TAF6 and TAF9. It has been shown that DPE-dependent basal transcription depends highly on the Inr (and vice versa) and on correct spacing between the two elements. The DPE

consensus sequence In molecular biology and bioinformatics, the consensus sequence (or canonical sequence) is the calculated order of most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment. It serves as a simplified r ...

was originally thought to be RGWCGTG, however more recent studies have suggested it to be the similar but more general sequence RGWYV(T). It is located about 28–33 nucleotides downstream of the

transcription Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the copying of DNA into RNA, the fir ...

start site.

Occurrence

It has been shown that the DPE is about as widely used as the TATA box in ''D. melanogaster''. While a DPE was found in many promoters that do not contain a TATA box, there are also promoters that contain both a TATA box and a DPE. The promoters of nearly all Hox genes of ''D. melanogaster'', with the exception of the evolutionarily most recent genes, ''

Ubx Ultrabithorax (Ubx) is a homeobox gene found in insects, and is used in the regulation of patterning in morphogenesis. There are many possible products of this gene, which function as transcription factors. Ubx is used in the specification of s ...

'' and
Abd-A
', contain a DPE motif and lack a TATA box. ''Drosophila'' promoters containing the DPE sequence include

', '' Antp P2'', ''

bride of sevenless ''Sevenless'' (''sev'') is a gene in '' Drosophila melanogaster'' that encodes a receptor tyrosine kinase protein essential to the development of R7 cells in the Drosophila embryonic eye. The drosophila ommatidium contains 8 distinct retinula o ...

'',
brown
',

',

',

', '' engrailed'',
Gsα
',

',

',

',

',

', and

'. In organisms other than ''D. melanogaster'', the promoter of the human and mouse '' IRF1'' gene has been found to contain a DPE consensus sequence at the appropriate distance from the transcription start site. This promoter, too, does not contain a TATA box. DPE has also been reported to play role in primitive Eukaryote '' Entamoeba histolytica''.

Notes

References

{{Transcription DNA Regulatory sequences