Abstract
Amphiregulin (AR), a heparin-binding, epidermal growth factor (EGF) receptor ligand has homology with EGF but exhibits a lower affinity for the EGF receptor than EGF. As the mature form of AR is truncated at the C terminus and lacks a conserved leucine residue known to be essential for high affinity binding of EGF to the EGF receptor, wild-type AR (AR1-84), a C-terminally extended AR construct incorporating six residues from the predicted coding sequence of AR (AR1-90) and a similarly extended construct with a Met86 to Leu substitution (AR1-90(leu86)) were expressed as recombinant proteins in yeast, purified by heparin affinity and C18 reverse phase chromatography and their relative biological activities determined. The growth factors were tested in mitogenesis and EGF receptor autophosphorylation assays and their relative order of potencies was found to be leu86 > met86 > wt. The AR1-90(leu86) construct was found to be 50- to 100-fold more active than wild type AR1-84 consistent with previously reported studies of the role of the equivalent C-terminal leucine in EGF or TGFα. Significantly, the C-terminally extended form of AR, AR1-90, which utilized six residues from the predicted coding sequence, was 10-times more active than wild type AR1-84. This difference in activity of the C-terminally extended form of AR may be of biological significance since differential proteolytic processing of the AR precursor in vivo could result in production of multiple forms of the growth factor with differing affinities for the EGF receptor and hence differing biological potencies.
| Original language | English |
|---|---|
| Pages (from-to) | 83-90 |
| Number of pages | 8 |
| Journal | BBA - Molecular Cell Research |
| Volume | 1266 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Apr 6 1995 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology
Cite this
Modulation of the receptor binding affinity of amphiregulin by modification of its carboxyl terminal tail. / Adam, R.; Drummond, Douglas Robert; Solic, N.; Holt, S. J.; Sharma, R. P.; Chamberlin, S. G.; Davies, D. E.
In: BBA - Molecular Cell Research, Vol. 1266, No. 1, 06.04.1995, p. 83-90.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Modulation of the receptor binding affinity of amphiregulin by modification of its carboxyl terminal tail
AU - Adam, R.
AU - Drummond, Douglas Robert
AU - Solic, N.
AU - Holt, S. J.
AU - Sharma, R. P.
AU - Chamberlin, S. G.
AU - Davies, D. E.
PY - 1995/4/6
Y1 - 1995/4/6
N2 - Amphiregulin (AR), a heparin-binding, epidermal growth factor (EGF) receptor ligand has homology with EGF but exhibits a lower affinity for the EGF receptor than EGF. As the mature form of AR is truncated at the C terminus and lacks a conserved leucine residue known to be essential for high affinity binding of EGF to the EGF receptor, wild-type AR (AR1-84), a C-terminally extended AR construct incorporating six residues from the predicted coding sequence of AR (AR1-90) and a similarly extended construct with a Met86 to Leu substitution (AR1-90(leu86)) were expressed as recombinant proteins in yeast, purified by heparin affinity and C18 reverse phase chromatography and their relative biological activities determined. The growth factors were tested in mitogenesis and EGF receptor autophosphorylation assays and their relative order of potencies was found to be leu86 > met86 > wt. The AR1-90(leu86) construct was found to be 50- to 100-fold more active than wild type AR1-84 consistent with previously reported studies of the role of the equivalent C-terminal leucine in EGF or TGFα. Significantly, the C-terminally extended form of AR, AR1-90, which utilized six residues from the predicted coding sequence, was 10-times more active than wild type AR1-84. This difference in activity of the C-terminally extended form of AR may be of biological significance since differential proteolytic processing of the AR precursor in vivo could result in production of multiple forms of the growth factor with differing affinities for the EGF receptor and hence differing biological potencies.
AB - Amphiregulin (AR), a heparin-binding, epidermal growth factor (EGF) receptor ligand has homology with EGF but exhibits a lower affinity for the EGF receptor than EGF. As the mature form of AR is truncated at the C terminus and lacks a conserved leucine residue known to be essential for high affinity binding of EGF to the EGF receptor, wild-type AR (AR1-84), a C-terminally extended AR construct incorporating six residues from the predicted coding sequence of AR (AR1-90) and a similarly extended construct with a Met86 to Leu substitution (AR1-90(leu86)) were expressed as recombinant proteins in yeast, purified by heparin affinity and C18 reverse phase chromatography and their relative biological activities determined. The growth factors were tested in mitogenesis and EGF receptor autophosphorylation assays and their relative order of potencies was found to be leu86 > met86 > wt. The AR1-90(leu86) construct was found to be 50- to 100-fold more active than wild type AR1-84 consistent with previously reported studies of the role of the equivalent C-terminal leucine in EGF or TGFα. Significantly, the C-terminally extended form of AR, AR1-90, which utilized six residues from the predicted coding sequence, was 10-times more active than wild type AR1-84. This difference in activity of the C-terminally extended form of AR may be of biological significance since differential proteolytic processing of the AR precursor in vivo could result in production of multiple forms of the growth factor with differing affinities for the EGF receptor and hence differing biological potencies.
UR - http://www.scopus.com/inward/record.url?scp=0028898965&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028898965&partnerID=8YFLogxK
U2 - 10.1016/0167-4889(94)00224-3
DO - 10.1016/0167-4889(94)00224-3
M3 - Article
C2 - 7718625
AN - SCOPUS:0028898965
VL - 1266
SP - 83
EP - 90
JO - Biochimica et Biophysica Acta - Molecular Cell Research
JF - Biochimica et Biophysica Acta - Molecular Cell Research
SN - 0167-4889
IS - 1
ER -