Structural insights into Cullin4-RING ubiquitin ligase remodelling by Vpr from simian immunodeficiency viruses
Fig 5
Cross-linking mass spectrometry (CLMS) analysis of CRL4DCAF1-CtD/ Vprmus/SAMHD1.
(A) Schematic representation of sulfo-SDA cross-links between CRL4DCAF1/Vprmus and SAMHD1, identified by CLMS. Proteins are colour-coded as in Figs 3 and 4, and SAMHD1 black/white. SAMHD1-CtD is highlighted in yellow. Crosslinks to the N-terminal SAMHD1 globular SAM and HD domains are coloured light brown, while cross-links to the N-terminal half of SAMHD1-CtD are highlighted in pink and cross-links to the C-terminal end of SAMHD1-CtD are coloured purple. (B) Sulfo-SDA cross-links from A, in the same colour scheme, mapped on the molecular model of CRL4-NEDD8DCAF1-CtD/Vprmus/SAMHD1 (state-2), obtained from cryo-EM analysis (Fig 3). SAMHD1-CtD density from the CRL4-NEDD8DCAF1-CtD/Vprmus/SAMHD1 (core) cryo-EM analysis (Fig 4) is shown as yellow mesh. (C) The accessible interaction space of SAMHD1-CtD, calculated by the DisVis server [61], consistent with at least 14 of 26 observed cross-links, is visualised as grey mesh. DCAF1-CtD and Vprmus are oriented and coloured as in Fig 4A.