Extended Data Fig. 6: Analysis of SHMT1 interaction with BRISC.

a, Elution profile of wild-type SHMT1 from an S75 16/600 size-exclusion chromatography column (data are representative of two independent experiments). b, Elution profile of SHMT1 containing mutated residues designed to break the tetrameric interface (left; data are from a single experiment). Structure of SHMT1 tetramer (PDB code 1RV4), highlighting residues that are important for tetramerization (right). c, BRISC DUB activity against a fluorogenic K63-linked diUb substrate in the presence of the indicated forms of SHMT1 and SHMT2. Data are mean ± s.e.m. of three independent experiments carried out in duplicate. d, Coomassie-stained SDS–PAGE analysis of the indicated SHMT1 and SHMT2 protein preparations (data are from a single experiment). e, Analytical size-exclusion chromatography runs of the indicated protein preparations. SHMT1 proteins were mixed with BRISC for 30 min before injecting on a 2.4-ml Superose 6 column (bottom traces). Traces on top are control runs. A BRISC–SHMT2ΔN run is shown for comparison (see Extended Data Fig. 8e for detailed analysis). f, Coomassie-stained SDS–PAGE analysis of the indicated peak fractions from size-exclusion runs shown in e. Data in e, f are representative of two independent experiments.