Fig. 1: CS synthases can form heterodimeric complexes.
From: Structural basis for human chondroitin sulfate chain polymerization
a Transient single- and co-expression of secreted CS synthase-encoding constructs in human embryonic kidney Freestyle 293-F cells. Proteins carrying an N-terminal secretion signal, SUMO (Small Ubiquitin-like Modifier) tag, and 6x His tag were detected in the cell culture medium by western blotting using an anti-His-HRP antibody. Expected molecular weights are 103 kDa for secreted CHSY1 (aa68-aa802), 98 kDa for CHPF (aa81-aa775), 102 kDa for CHSY3 (aa157-aa882), and 101 kDa for CHPF2 (aa57-aa772). Experiment was performed in duplicate (see Supplementary Fig 1b). Source data are provided as a Source Data file. b Structural models for the six potential heterodimeric CS polymerase complexes were predicted using AlphaFold 233,34. Models are shown in cartoon representation with CHSY1 in green, CHPF in gray, CHSY3 in orange, and CHPF2 in light blue. The N-terminal anchoring helices and flexible stem regions, which were omitted during model prediction, were drawn by hand. The corresponding predicted aligned error matrices are shown below. AlphaFold 2-predicted models are provided as a Source Data file.
