한빛사논문
Kevin Wu 1,2,5, Samuel Itskanov 3,5, Diane L. Lynch 4, Yuanyuan Chen 1,2, Aasha Turner 1, James C. Gumbart 4 & Eunyong Park 1,2,*
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
2California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, USA.
3Biophysics Graduate Program, University of California, Berkeley, CA 94720, USA.
4School of Physics and School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
5These authors contributed equally: Kevin Wu, Samuel Itskanov.
*Corresponding author: correspondence to Eunyong Park
Abstract
Doa10 (MARCHF6 in metazoans) is a large polytopic membrane-embedded E3 ubiquitin ligase in the endoplasmic reticulum (ER) that plays an important role in quality control of cytosolic and ER proteins. Although Doa10 is highly conserved across eukaryotes, it is not understood how Doa10 recognizes its substrates. Here, we define the substrate recognition mechanism of Doa10 by structural and functional analyses on Saccharomyces cerevisiae Doa10 and its model substrates. Cryo-EM analysis shows that Doa10 has unusual architecture with a large lipid-filled central cavity, and its conserved middle domain forms an additional water-filled lateral tunnel open to the cytosol. Our biochemical data and molecular dynamics simulations suggest that the entrance of the substrate’s degron peptide into the lateral tunnel is required for efficient polyubiquitination. The N- and C-terminal membrane domains of Doa10 seem to form fence-like features to restrict polyubiquitination to those proteins that can access the central cavity and lateral tunnel. Our study reveals how extended hydrophobic sequences at the termini of substrate proteins are recognized by Doa10 as a signal for quality control.
논문정보
관련 링크
연구자 ID
관련분야 연구자보기
소속기관 논문보기
관련분야 논문보기
해당논문 저자보기