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Title: Designer interface peptide grafts target estrogen receptor alpha dimerization

Abstract

The nuclear transcription factor estrogen receptor alpha (ERα), triggered by its cognate ligand estrogen, regulates a variety of cellular signaling events. ERα is expressed in 70% of breast cancers and is a widely validated target for anti-breast cancer drug discovery. Administration of anti-estrogen to block estrogen receptor activation is still a viable anti-breast cancer treatment option but anti-estrogen resistance has been a significant bottle-neck. Dimerization of estrogen receptor is required for ER activation. Blocking ERα dimerization is therefore a complementary and alternative strategy to combat anti-estrogen resistance. Dimer interface peptide “I-box” derived from ER residues 503–518 specifically blocks ER dimerization. Recently using a comprehensive molecular simulation we studied the interaction dynamics of ERα LBDs in a homo-dimer. Based on this study, we identified three interface recognition peptide motifs LDKITDT (ERα residues 479–485), LQQQHQRLAQ (residues 497–506), and LSHIRHMSNK (residues 511–520) and reported the suitability of using LQQQHQRLAQ (ER 497–506) as a template to design inhibitors of ERα dimerization. Stability and self-aggregation of peptide based therapeutics poses a significant bottle-neck to proceed further. In this study utilizing peptide grafted to preserve their pharmacophoric recognition motif and assessed their stability and potential to block ERα mediated activity in silico and in vitro. The Graftedmore » peptides blocked ERα mediated cell proliferation and viability of breast cancer cells but did not alter their apoptotic fate. We believe the structural clues identified in this study can be used to identify novel peptidometics and small molecules that specifically target ER dimer interface generating a new breed of anti-cancer agents. - Highlights: • Designer peptide grafts retain core molecular recognition motif during MD simulations. • Designer peptide grafts with Poly-ALA helix form stable complexes with estrogen receptor in silico. • Inhibitor peptides significantly decrease estrogen induced cell proliferation of ER positive breast cancer cells in vitro.« less

Authors:
 [1];  [2];  [1];  [2]
  1. Laboratory of Computational Biophysics & Bioengineering, Department of Physics, Tougaloo College, Tougaloo, MS 39174 (United States)
  2. Department of Pharmacology and Toxicology, University of Buffalo, Buffalo, NY 14214 (United States)
Publication Date:
OSTI Identifier:
22606207
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 478; Journal Issue: 1; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CELL PROLIFERATION; DIMERIZATION; DIMERS; DRUGS; ESTROGENS; GRAFTS; IN VITRO; LIGANDS; MAMMARY GLANDS; MOLECULES; NECK; NEOPLASMS; PEPTIDES; RECEPTORS; TRANSCRIPTION FACTORS

Citation Formats

Chakraborty, S., Asare, B.K., Biswas, P.K., E-mail: pbiswas@tougaloo.edu, and Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu. Designer interface peptide grafts target estrogen receptor alpha dimerization. United States: N. p., 2016. Web. doi:10.1016/J.BBRC.2016.07.083.
Chakraborty, S., Asare, B.K., Biswas, P.K., E-mail: pbiswas@tougaloo.edu, & Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu. Designer interface peptide grafts target estrogen receptor alpha dimerization. United States. doi:10.1016/J.BBRC.2016.07.083.
Chakraborty, S., Asare, B.K., Biswas, P.K., E-mail: pbiswas@tougaloo.edu, and Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu. 2016. "Designer interface peptide grafts target estrogen receptor alpha dimerization". United States. doi:10.1016/J.BBRC.2016.07.083.
@article{osti_22606207,
title = {Designer interface peptide grafts target estrogen receptor alpha dimerization},
author = {Chakraborty, S. and Asare, B.K. and Biswas, P.K., E-mail: pbiswas@tougaloo.edu and Rajnarayanan, R.V., E-mail: rajendra@buffalo.edu},
abstractNote = {The nuclear transcription factor estrogen receptor alpha (ERα), triggered by its cognate ligand estrogen, regulates a variety of cellular signaling events. ERα is expressed in 70% of breast cancers and is a widely validated target for anti-breast cancer drug discovery. Administration of anti-estrogen to block estrogen receptor activation is still a viable anti-breast cancer treatment option but anti-estrogen resistance has been a significant bottle-neck. Dimerization of estrogen receptor is required for ER activation. Blocking ERα dimerization is therefore a complementary and alternative strategy to combat anti-estrogen resistance. Dimer interface peptide “I-box” derived from ER residues 503–518 specifically blocks ER dimerization. Recently using a comprehensive molecular simulation we studied the interaction dynamics of ERα LBDs in a homo-dimer. Based on this study, we identified three interface recognition peptide motifs LDKITDT (ERα residues 479–485), LQQQHQRLAQ (residues 497–506), and LSHIRHMSNK (residues 511–520) and reported the suitability of using LQQQHQRLAQ (ER 497–506) as a template to design inhibitors of ERα dimerization. Stability and self-aggregation of peptide based therapeutics poses a significant bottle-neck to proceed further. In this study utilizing peptide grafted to preserve their pharmacophoric recognition motif and assessed their stability and potential to block ERα mediated activity in silico and in vitro. The Grafted peptides blocked ERα mediated cell proliferation and viability of breast cancer cells but did not alter their apoptotic fate. We believe the structural clues identified in this study can be used to identify novel peptidometics and small molecules that specifically target ER dimer interface generating a new breed of anti-cancer agents. - Highlights: • Designer peptide grafts retain core molecular recognition motif during MD simulations. • Designer peptide grafts with Poly-ALA helix form stable complexes with estrogen receptor in silico. • Inhibitor peptides significantly decrease estrogen induced cell proliferation of ER positive breast cancer cells in vitro.},
doi = {10.1016/J.BBRC.2016.07.083},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 478,
place = {United States},
year = 2016,
month = 9
}
  • Highlights: Black-Right-Pointing-Pointer ZNF131 directly interacts with ER{alpha}. Black-Right-Pointing-Pointer The binding affinity of ZNF131 to ER{alpha} increases upon E2 stimulation. Black-Right-Pointing-Pointer ZNF131 inhibits ER{alpha}-mediated trans-activation by suppressing its homo-dimerization. Black-Right-Pointing-Pointer ZNF131 inhibits ER{alpha}-dimerization and E2-induced breast cancer cell proliferation. Black-Right-Pointing-Pointer ZNF131 inhibits estrogen signaling by acting as an ER{alpha}-co-repressor. -- Abstract: Steroid hormone estrogen elicits various physiological functions, many of which are mediated through two structurally and functionally distinct estrogen receptors, ER{alpha} and ER{beta}. The functional role of zinc finger protein 131 (ZNF131) is poorly understood, but it is assumed to possess transcriptional regulation activity due to the presence of amore » DNA binding motif. A few recent reports, including ours, revealed that ZNF131 acts as a negative regulator of ER{alpha} and that SUMO modification potentiates the negative effect of ZNF131 on estrogen signaling. However, its molecular mechanism for ER{alpha} inhibition has not been elucidated in detail. Here, we demonstrate that ZNF131 directly interacts with ER{alpha}, which consequently inhibits ER{alpha}-mediated trans-activation by suppressing its homo-dimerization. Moreover, we show that the C-terminal region of ZNF131 containing the SUMOylation site is necessary for its inhibition of estrogen signaling. Taken together, these data suggest that ZNF131 inhibits estrogen signaling by acting as an ER{alpha}-co-repressor.« less
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