A GC-rich element confers epidermal growth factor responsiveness to transcription from the gastrin promoter.
AUTOR(ES)
Merchant, J L
RESUMO
Epidermal growth factor (EGF) and transforming growth factor alpha are important determinants of mucosal integrity in the gastrointestinal tract, and they act both directly and indirectly to prevent ulceration in the stomach. Consistent with this physiological role, EGF stimulates transcription of gastrin, a peptide hormone which regulates gastric acid secretion and mucosal growth. EGF stimulation of gastrin transcription is mediated by a GC-rich gastrin EGF response element (gERE) (GGGGCGGGGTGGGGGG) which lies between -54 and -68 in the human gastrin promoter. The gERE sequence also confers weaker responsiveness to phorbol ester stimulation. The gERE sequence differs from previously described EGF response elements. The gERE DNA sequence specifically interacts with a GH4 DNA-binding protein distinct from previously described transcription factors (Egr-1 and AP2) which bind GC-rich sequences and mediate transcriptional activation by growth factors. Furthermore, the gERE element does not bind the Sp1 transcription factor even though the gERE sequence contains a high-affinity Sp1-binding site (GGCGGG).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=360038Documentos Relacionados
- The repeated GC-rich motifs upstream from the TATA box are important elements of the SV40 early promoter.
- The anaerobic responsive element contains two GC-rich sequences essential for binding a nuclear protein and hypoxic activation of the maize Adh1 promoter.
- DNA helix: the importance of being GC-rich
- Betaine improves the PCR amplification of GC-rich DNA sequences.
- A novel GC-rich dispersed repeat sequence in Drosophila melanogaster.