Comparison of activity, structure, and dynamics of SF-1 and LRH-1 complexed with small molecule modulators.

Michael L Cato, Emma H D'Agostino, Racheal M Spurlin, Autumn R Flynn, Jeffery L Cornelison, Alyssa M Johnson, Rei A Fujita, Sarah M Abraham, Nathan T Jui, Eric A Ortlund

The Journal of biological chemistry 2023 Aug

filter terms:

Steroidogenic factor-1 (SF-1) is a phospholipid-sensing nuclear receptor expressed in the adrenal glands, gonads, and hypothalamus which controls steroidogenesis and metabolism. There is significant therapeutic interest in SF-1 because of its oncogenic properties in adrenocortical cancer. Synthetic modulators are attractive for targeting SF-1 for clinical and laboratory purposes due to the poor pharmaceutical properties of its native phospholipid ligands. While small molecule agonists targeting SF-1 have been synthesized, no crystal structures have been reported of SF-1 in complexes with synthetic compounds. This has prevented the establishment of structure-activity relationships that would enable better characterization of ligand-mediated activation and improvement in current chemical scaffolds. Here, we compare the effects of small molecules in SF-1 and its close homolog, liver receptor homolog-1 (LRH-1), and identify several molecules that specifically activate LRH-1. We also report the first crystal structure of SF-1 in complex with a synthetic agonist that displays low nanomolar affinity and potency for SF-1. We use this structure to explore the mechanistic basis for small molecule agonism of SF-1, especially compared to LRH-1, and uncover unique signaling pathways that drive LRH-1 specificity. Molecular dynamics simulations reveal differences in protein dynamics at the pocket mouth as well as ligand-mediated allosteric communication from this region to the coactivator binding interface. Our studies, therefore, shed important insight into the allostery driving SF-1 activity and show potential for modulation of LRH-1 over SF-1. Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.

Citation

Michael L Cato, Emma H D'Agostino, Racheal M Spurlin, Autumn R Flynn, Jeffery L Cornelison, Alyssa M Johnson, Rei A Fujita, Sarah M Abraham, Nathan T Jui, Eric A Ortlund. Comparison of activity, structure, and dynamics of SF-1 and LRH-1 complexed with small molecule modulators. The Journal of biological chemistry. 2023 Aug;299(8):104921