Biophysical and structural characterization of the GR/COUP-TFII complex

• Grant number: 19/13928-8
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: October 01, 2019
• End date: December 31, 2019
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Ana Carolina Migliorini Figueira
• Grantee: Izabella Luisa Tambones
• Supervisor: Albane Coirier Le Maire
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Institution abroad: Centre de Biochimie Structurale de Montpellier (CBS), France
• Associated to the scholarship: 18/02481-0 - Regulation of the SMyHC iii promoter by the nuclear receptors AR, GR and Coup-TFII: a solo or joint work?, BP.MS

Abstract

Nuclear Receptors (NRs) belong to a superfamily of transcription factors regulated by ligands. They act on the transcription of specific genes and they are involved in several processes such as cell proliferation, homeostasis, metabolism and others. The receptors COUP-TFII (Chicken ovalbumin upstream promoter-transcription factor) and GR (glucocorticoid receptor) have been associated to diverse biological contexts, especially embryonic cardiac development. Although these two receptors generally exert their actions as homodimers, the interaction between COUP-TFII and GR was demonstrated by glutathione-S-transferase pull-down assay. Our master's results, obtained by microscale thermophoresis and pull-down assay, reinforce and quantify the interaction between these receptors, which bind to each other with high affinity. In order to better understand the modes of interaction of these receptors and to build structural models of this unusual NR heterodimer, the present project aims at characterizing the protein-protein interactions involving GR and COUPTF-II receptors. Proteins will be expressed using bacterial Escherichia coli cells (BL21 DE3) and will be purified by affinity, gel-filtration and ion exchange chromatography. The GR-COUP-TFII complexes will be formed from the expressed and purified proteins separately and purified by gel-filtration. A complete biophysical characterization of the complex will be conducted at the Centre de Biochimie Structurale in Montpellier (France), as well as the SAXS analysis, that will be conducted in collaboration with this team, at the synchrotrons DESY (Hamburg, Germany) and SOLEIL (Paris). (AU)