7SVR

The complex of dephosphorylated human cystic fibrosis transmembrane conductance regulator (CFTR) and Lumacaftor (VX-809)

Summary for 7SVR

• Entry DOI: 10.2210/pdb7svr/pdb
• EMDB information: 25452
• Descriptor: Cystic fibrosis transmembrane conductance regulator, Lumacaftor (3 entities in total)
• Functional Keywords: abc transporter, ion channel, folding correction, membrane protein, atp-binding protein
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 2
• Total formula weight: 170422.87

Authors

Fiedorczuk, K.,Chen, J. (deposition date: 2021-11-19, release date: 2022-01-12, Last modification date: 2024-02-28)

Primary citation

Fiedorczuk, K.,Chen, J.
Mechanism of CFTR correction by type I folding correctors.
Cell, 185:158-168.e11, 2022

PubMed Abstract: Small molecule chaperones have been exploited as therapeutics for the hundreds of diseases caused by protein misfolding. The most successful examples are the CFTR correctors, which transformed cystic fibrosis therapy. These molecules revert folding defects of the ΔF508 mutant and are widely used to treat patients. To investigate the molecular mechanism of their action, we determined cryo-electron microscopy structures of CFTR in complex with the FDA-approved correctors lumacaftor or tezacaftor. Both drugs insert into a hydrophobic pocket in the first transmembrane domain (TMD1), linking together four helices that are thermodynamically unstable. Mutating residues at the binding site rendered ΔF508-CFTR insensitive to lumacaftor and tezacaftor, underscoring the functional significance of the structural discovery. These results support a mechanism in which the correctors stabilize TMD1 at an early stage of biogenesis, prevent its premature degradation, and thereby allosterically rescuing many disease-causing mutations.

PubMed: 34995514
DOI: 10.1016/j.cell.2021.12.009

Experimental method

ELECTRON MICROSCOPY (3.9 Å)