Fig. 1: The high-order assembly of KAT2A in complex with succinyl-CoA.

a–c Octahedral complex of KAT2A in association with succinyl-CoA. The protein molecules are shown as ribbons, whereas the substrate succinyl-CoA molecules are shown in red as space-filling models. The complex is viewed along a 2-fold, b 3-fold, and c 4-fold symmetry axes. d–f Three different KAT2A oligomers found in the octahedral assembly. A dimer (d), tetramer (e), and trimer (f) are shown. The upper panels in these three figures represent top views along the symmetry axes from the outside of the octahedron. The lower panels are views from the side, with the molecules at the back removed for clarity. Secondary structure elements at the oligomer interfaces are labeled. g–i Hydrogen bonds and salt bridges at the dimeric (g) and tetrameric (h, i) interfaces. The protein molecules are shown as ribbons, whereas the interacting residues are labeled and shown as sticks. The molecular regions shown in g, h, and i correspond to the rectangle box highlighted in d, solid rectangle box in e, and dashed rectangle box in e. j Gel-filtration analyses of purified recombinant His-KAT2A (497–662) (upper panel) and wild-type (WT) Flag-rKAT2A (full-length) in the nucleus of 293T cells (lower panel). Bacterially purified His-KAT2A (497–662) or the nuclear lysate from WT Flag-rKAT2A (full-length)-expressing 293T cells was injected into an AKTA Purifier system with a HiPrep 16/60 Sephacryl S-300 High Resolution column for molecular weight-dependent fractionation. The elution from 18 ml to 120 ml was collected with 3 ml for each fraction. Immunoblot analysis of each fraction was performed with the indicated antibodies. The elution volume for each molecular weight marker is indicated. A second peak of His-tagged catalytic domain of KAT2A near 110 ml was observed; this was likely due to the nonspecific interaction of the catalytic domain of KAT2A with the resin. The same peak was not affected by increasing the NaCl concentration from 0.15 M to 0.5 M. k WT Myc-rKAT2A was co-transfected with WT Flag-rKAT2A or a control vector into U251 glioblastoma cells. Immunoprecipitation was performed with an anti-Flag antibody. Immunoblot analysis was performed with the indicated antibodies