Download MendeleyCrystal structure of the human sterol transporter ABCG5/ABCG8.
Lee, J.Y., Kinch, L.N., Borek, D.M., Wang, J., Wang, J., Urbatsch, I.L., Xie, X.S., Grishin, N.V., Cohen, J.C., Otwinowski, Z., Hobbs, H.H., Rosenbaum, D.M.(2016) Nature 533: 561-564
- PubMed: 27144356
- DOI: https://doi.org/10.1038/nature17666
- Primary Citation of Related Structures:
5DO7 - PubMed Abstract:
ATP binding cassette (ABC) transporters play critical roles in maintaining sterol balance in higher eukaryotes. The ABCG5/ABCG8 heterodimer (G5G8) mediates excretion of neutral sterols in liver and intestines. Mutations disrupting G5G8 cause sitosterolaemia, a disorder characterized by sterol accumulation and premature atherosclerosis. Here we use crystallization in lipid bilayers to determine the X-ray structure of human G5G8 in a nucleotide-free state at 3.9 Å resolution, generating the first atomic model of an ABC sterol transporter. The structure reveals a new transmembrane fold that is present in a large and functionally diverse superfamily of ABC transporters. The transmembrane domains are coupled to the nucleotide-binding sites by networks of interactions that differ between the active and inactive ATPases, reflecting the catalytic asymmetry of the transporter. The G5G8 structure provides a mechanistic framework for understanding sterol transport and the disruptive effects of mutations causing sitosterolaemia.
Organizational Affiliation:
Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA.
