TY - JOUR
T1 - Epidermal growth factor stimulation of the human gastrin promoter requires Sp1
AU - Merchant, J. L.
AU - Shiotani, A.
AU - Mortensen, E. R.
AU - Shumaker, D. K.
AU - Abraczinskas, D. R.
PY - 1995
Y1 - 1995
N2 - Growth factors coordinately regulate a variety of different genes to stimulate cellular proliferation. In the stomach, gastrin, epidermal growth factor (EGF), and transforming growth factor-α all mediate gastric mucosal homeostasis by promoting cell renewal. We have previously shown that EGF and phorbol esters stimulate the human gastrin promoter through a novel GC-rich DNA element 5'--68GGGGCGGGGTGGGGGG-53 called gERE (gastrin EGF response element). In this report, we show that three factors bind to this element, the transcription factor Sp1 and two fast migrating complexes designated gastrin EGF response proteins (gERP 1 and 2). To understand how these factors bind and confer EGF responsiveness, mutations of gERE were tested in vitro for protein binding and in vivo for promoter activation. Both gel shift assays and UV cross-linking studies revealed that the factors bind to overlapping domains, Sp1 to the 5' half-site and gERP 1 and 2 to the 3' half- site. Placing either the 5' or 3' mutations upstream of a minimal gastrin promoter abolished EGF induction. Therefore both the 5' and 3' domains were required to confer EGF induction. Collectively, these results demonstrate that complex interactions between Sp1 and other factors binding to overlapping gERE half-sites confer EGF responsiveness to the gastrin promoter.
AB - Growth factors coordinately regulate a variety of different genes to stimulate cellular proliferation. In the stomach, gastrin, epidermal growth factor (EGF), and transforming growth factor-α all mediate gastric mucosal homeostasis by promoting cell renewal. We have previously shown that EGF and phorbol esters stimulate the human gastrin promoter through a novel GC-rich DNA element 5'--68GGGGCGGGGTGGGGGG-53 called gERE (gastrin EGF response element). In this report, we show that three factors bind to this element, the transcription factor Sp1 and two fast migrating complexes designated gastrin EGF response proteins (gERP 1 and 2). To understand how these factors bind and confer EGF responsiveness, mutations of gERE were tested in vitro for protein binding and in vivo for promoter activation. Both gel shift assays and UV cross-linking studies revealed that the factors bind to overlapping domains, Sp1 to the 5' half-site and gERP 1 and 2 to the 3' half- site. Placing either the 5' or 3' mutations upstream of a minimal gastrin promoter abolished EGF induction. Therefore both the 5' and 3' domains were required to confer EGF induction. Collectively, these results demonstrate that complex interactions between Sp1 and other factors binding to overlapping gERE half-sites confer EGF responsiveness to the gastrin promoter.
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U2 - 10.1074/jbc.270.11.6314
DO - 10.1074/jbc.270.11.6314
M3 - Article
C2 - 7890769
AN - SCOPUS:0028933246
SN - 0021-9258
VL - 270
SP - 6314
EP - 6319
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 11
ER -