Clamping, bending, and twisting inter-domain motions in the misfold-recognizing portion of UDP-glucose:glycoprotein glucosyltransferase

DOI: 10.1016/j.str.2020.11.017

Authors: Carlos P. Modenutti (Universidad de Buenos Aires; Ciudad Universitaria) , Juan I. Blanco Capurro (Universidad de Buenos Aires; Ciudad Universitaria) , Roberta Ibba (University of Oxford; Università degli Studi di Sassari) , Dominic S. Alonzi (University of Oxford) , Mauro N. Song (Universidad de Buenos Aires; Ciudad Universitaria) , Snežana Vasiljević (University of Oxford) , Abhinav Kumar (University of Oxford) , Anu V. Chandran (University of Oxford) , Gabor Tax (University of Leicester) , Lucia Marti (C.N.R.) , Johan C. Hill (University of Oxford) , Andrea Lia (University of Oxford; University of Leicester; C.N.R.) , Mario Hensen (University of Oxford) , Thomas Waksman (University of Oxford) , Jonathan Rushton (University of Oxford) , Simone Rubichi (University of Oxford; C.N.R.) , Angelo Santino (C.N.R.) , Marcelo A. Martí (Universidad de Buenos Aires; Ciudad Universitaria) , Nicole Zitzmann (University of Oxford) , Pietro Roversi (University of Oxford; University of Leicester)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Structure

State: Published (Approved)
Published: December 2020
Diamond Proposal Number(s): 12346 , 18069

Abstract: UDP-glucose:glycoprotein glucosyltransferase (UGGT) flags misfolded glycoproteins for ER retention. We report crystal structures of full-length Chaetomium thermophilum UGGT (CtUGGT), two CtUGGT double-cysteine mutants, and its TRXL2 domain truncation (CtUGGT-ΔTRXL2). CtUGGT molecular dynamics (MD) simulations capture extended conformations and reveal clamping, bending, and twisting inter-domain movements. We name “Parodi limit” the maximum distance on the same glycoprotein between a site of misfolding and an N-linked glycan that can be reglucosylated by monomeric UGGT in vitro, in response to recognition of misfold at that site. Based on the MD simulations, we estimate the Parodi limit as around 70–80 Å. Frequency distributions of distances between glycoprotein residues and their closest N-linked glycosylation sites in glycoprotein crystal structures suggests relevance of the Parodi limit to UGGT activity in vivo. Our data support a “one-size-fits-all adjustable spanner” UGGT substrate recognition model, with an essential role for the UGGT TRXL2 domain.

Journal Keywords: UGGT; glycoprotein folding; negative-stain EM; molecular dynamics; Parodi limit; misfolding; misfold sensing; X-ray diffraction; re-glucosylation; GT24 domain

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I03-Macromolecular Crystallography , I04-Macromolecular Crystallography , I24-Microfocus Macromolecular Crystallography

Added On: 13/01/2021 11:57

Documents:
1-s2.0-S0969212620304640-main.pdf

Discipline Tags:

Biochemistry Chemistry Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)