Structural hypotheses and computational studies of asciminib resistance mechanisms for M244V and F359V. (A) Structural models of autoinhibited ABL1-SH2/SH3 complex (left; PDBID: 5MO4) with asciminib bound, and activated ABL1-SH2 complex (right; PDBID: 4XEY). Crystallographic active site ligands are omitted for clarity. M244 is shown as yellow spheres, and F359 is shown as purple spheres. (B) Relative position and distance between points of mutation and asciminib binding pocket. (C) αC helix RMSD for wild type (WT), M244V, and F359V simulations with respect to the average structure from the WT simulation. (D) Rearrangements of top of the N-terminal kinase domain, which interfaces SH2 domain in activated structure, for M244V compared with activated structure (top, dark blue) and autoinhibited structure (bottom, light blue). (E) Surface representation of ABL1 kinase N-lobe-SH2 interaction in the activated ABL1 conformation (PDBID: 4XEY). Colors: N-lobe (red), C-lobe (gray), hinge (black), SH2 (gold), asciminib (pink), M244 (yellow), F359 (purple), and I164 (green). (F) Molecular dynamic snapshots of M244V exhibit a well-formed complementary pocket for I164 (bright green) in the SH2 domain, which defines the molecular interaction surface of the kinase N-lobe with the SH2 domain (middle). Compare with similar observation for crystallographic model of activated conformation (top), and contrast with MD snapshots from F359V condition for which no such complementary pocket is significantly observed (bottom). (G) C-lobe α helix bundle (gray) with F359V on one end (purple) and asciminib bound at other end (pink). SH2 domain (yellow) interactions in the autoinhibited conformation could play a role in mechanisms that impact the arrangement of the C-lobe helix bundle.