Dataset Information

Structural basis for heme-dependent NCoR binding to the transcriptional repressor REV-ERBβ

ABSTRACT: Heme is the endogenous ligand for the constitutively repressive REV-ERB nuclear receptors, REV-ERBα (NR1D1) and REV-ERBβ (NR1D2), but how heme regulates REV-ERB activity remains unclear. While cellular studies indicate heme is required for the REV-ERBs to bind the corepressor NCoR and repress transcription, fluorescence-based biochemical assays and crystal structures suggest that heme displaces NCoR. Here, we found that heme artifactually influences detection of NCoR interaction in fluorescence-based assays. Using fluorescence-independent methods, including isothermal titration calorimetry, NMR spectroscopy, and XL-MS, we determined that heme remodels the thermodynamic profile of NCoR binding to REV-ERBβ ligand-binding domain (LBD) and directly increases LBD binding affinity for an NCoR interaction motif. We further report two crystal structures of REV-ERBβ LBD cobound to heme and NCoR peptides, which reveal the heme-dependent NCoR binding mode. By resolving previous contradictory biochemical, structural, and cellular studies, our findings should facilitate renewed progress toward understanding heme-dependent REV-ERB activity.

INSTRUMENT(S):

ORGANISM(S): Mus Musculus (mouse)

SUBMITTER: Timothy Strutzenberg

LAB HEAD: Patrick Robert Griffin

PROVIDER: PXD021761 | Pride | 2021-02-24

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20200205_TRY_RevERb_HEME_REP1.raw	Raw
	20200205_TRY_RevERb_HEME_REP2.raw	Raw
	20200205_TRY_RevERb_HEME_REP3.raw	Raw
	20200205_TRY_RevERb_NCoR1_HEME_REP1.raw	Raw
	20200205_TRY_RevERb_NCoR1_HEME_REP2.raw	Raw

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Publications

Structural basis for heme-dependent NCoR binding to the transcriptional repressor REV-ERBβ.

Mosure Sarah A SA Strutzenberg Timothy S TS Shang Jinsai J Munoz-Tello Paola P Solt Laura A LA Griffin Patrick R PR Kojetin Douglas J DJ

Science advances 20210127 5

Heme is the endogenous ligand for the constitutively repressive REV-ERB nuclear receptors, REV-ERBα (NR1D1) and REV-ERBβ (NR1D2), but how heme regulates REV-ERB activity remains unclear. Cellular studies indicate that heme is required for the REV-ERBs to bind the corepressor NCoR and repress transcription. However, fluorescence-based biochemical assays suggest that heme displaces NCoR; here, we show that this is due to a heme-dependent artifact. Using ITC and NMR spectroscopy, we show that heme ...[more]

PMID: 33571111

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