TY - JOUR
T1 - The N-terminal Regions of Estrogen Receptor α and β Are Unstructured in Vitro and Show Different TBP Binding Properties
AU - Wärnmark, Anette
AU - Wikström, Anja
AU - Wright, Anthony P.H.
AU - Gustafsson, Jan Åke
AU - Härd, Torleif
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2001/12/7
Y1 - 2001/12/7
N2 - The N-terminal regions of the estrogen receptor α (ERα-N) and β (ERβ-N) were expressed and purified to homogeneity. Using NMR and circular dichroism spectroscopy, we conclude that both ERα-N and ERβ-N are unstructured in solution. The TATA box-binding protein (TBP) has been shown previously to interact with ERα-N in vitro and to potentiate ER-activated transcription. We used surface plasmon resonance and circular dichroism spectroscopy to confirm and further characterize the ER-N-TBP interaction. Our results show that the intrinsically unstructured ERα-N interacts with TBP, and suggest that structural changes are induced in ERα-N upon TBP interaction. Conformational changes upon target factor interaction have not previously been demonstrated for any N-terminal region of nuclear receptors. In addition, no binding of ERα-N to TBP was detected. This difference in TBP binding could imply differential recruitment of target proteins by ERα-N and ERβ-N. The affinity of the ERβ-N-TBP interaction was determined to be in the micromolar range (KD = 10-6 to 10-5 M). Our results support models of TBP as a target protein for the N-terminal activation domain of ERα. Further, our results suggest that target proteins can induce and/or stabilize ordered structure in N-terminal regions of nuclear receptors upon interaction.
AB - The N-terminal regions of the estrogen receptor α (ERα-N) and β (ERβ-N) were expressed and purified to homogeneity. Using NMR and circular dichroism spectroscopy, we conclude that both ERα-N and ERβ-N are unstructured in solution. The TATA box-binding protein (TBP) has been shown previously to interact with ERα-N in vitro and to potentiate ER-activated transcription. We used surface plasmon resonance and circular dichroism spectroscopy to confirm and further characterize the ER-N-TBP interaction. Our results show that the intrinsically unstructured ERα-N interacts with TBP, and suggest that structural changes are induced in ERα-N upon TBP interaction. Conformational changes upon target factor interaction have not previously been demonstrated for any N-terminal region of nuclear receptors. In addition, no binding of ERα-N to TBP was detected. This difference in TBP binding could imply differential recruitment of target proteins by ERα-N and ERβ-N. The affinity of the ERβ-N-TBP interaction was determined to be in the micromolar range (KD = 10-6 to 10-5 M). Our results support models of TBP as a target protein for the N-terminal activation domain of ERα. Further, our results suggest that target proteins can induce and/or stabilize ordered structure in N-terminal regions of nuclear receptors upon interaction.
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U2 - 10.1074/jbc.M107875200
DO - 10.1074/jbc.M107875200
M3 - Article
C2 - 11595744
AN - SCOPUS:0035824562
SN - 0021-9258
VL - 276
SP - 45939
EP - 45944
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 49
ER -