5TGK

Nucleotide-binding domain 1 of the human cystic fibrosis transmembrane conductance regulator (CFTR) with dATP

Summary for 5TGK

• Entry DOI: 10.2210/pdb5tgk/pdb
• Related: 5TF7 5TF8 5TFA 5TFB 5TFC 5TFD 5TFE 5TFF 5TFG 5TFH 5TFI 5TFJ
• Descriptor: Cystic fibrosis transmembrane conductance regulator, MAGNESIUM ION, 2'-DEOXYADENOSINE 5'-TRIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: hnbd1, cftr, abc transport, datp, hydrolase
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 26040.90

Authors

Wang, C.,Aleksandrov, A.A.,Yang, Z.,Forouhar, F.,Proctor, E.,Kota, P.,An, J.,Kaplan, A.,Khazanov, N.,Boel, G.,Stockwell, B.R.,Senderowitz, H.,Dokholyan, N.V.,Riordan, J.R.,Brouillette, C.G.,Hunt, J.F. (deposition date: 2016-09-28, release date: 2018-05-09, Last modification date: 2023-10-04)

Primary citation

Wang, C.,Aleksandrov, A.A.,Yang, Z.,Forouhar, F.,Proctor, E.A.,Kota, P.,An, J.,Kaplan, A.,Khazanov, N.,Boel, G.,Stockwell, B.R.,Senderowitz, H.,Dokholyan, N.V.,Riordan, J.R.,Brouillette, C.G.,Hunt, J.F.
Ligand binding to a remote site thermodynamically corrects the F508del mutation in the human cystic fibrosis transmembrane conductance regulator.
J. Biol. Chem., 2018

PubMed Abstract: Many disease-causing mutations impair protein stability. Here, we explore a thermodynamic strategy to correct the disease-causing F508del mutation in the human cystic fibrosis transmembrane conductance regulator (hCFTR). F508del destabilizes nucleotide-binding domain 1 (hNBD1) in hCFTR relative to an aggregation-prone intermediate. We developed a fluorescence self-quenching assay for compounds that prevent aggregation of hNBD1 by stabilizing its native conformation. Unexpectedly, we found that dTTP and nucleotide analogs with exocyclic methyl groups bind to hNBD1 more strongly than ATP and preserve electrophysiological function of full-length F508del-hCFTR channels at temperatures up to 37 °C. Furthermore, nucleotides that increase open-channel probability, which reflects stabilization of an interdomain interface to hNBD1, thermally protect full-length F508del-hCFTR even when they do not stabilize isolated hNBD1. Therefore, stabilization of hNBD1 itself or of one of its interdomain interfaces by a small molecule indirectly offsets the destabilizing effect of the F508del mutation on full-length hCFTR. These results indicate that high-affinity binding of a small molecule to a remote site can correct a disease-causing mutation. We propose that the strategies described here should be applicable to identifying small molecules to help manage other human diseases caused by mutations that destabilize native protein conformation.

PubMed: 29903914
DOI: 10.1074/jbc.RA117.000819

Experimental method

X-RAY DIFFRACTION (1.912 Å)