Fig. 4: Structural basis for highly selective interactions between DLK1 and ACVR2B.
From: Molecular mechanism of Activin receptor inhibition by DLK1
A The structure of ACVR2A (PDB ID: 5NH3) was superimposed onto ACVR2B in the DLK1-ACVR2B complex structure (PDB ID: 9D20). B A zoom window shows Phe82 of ACVR2B inserted into the pocket formed by DLK1 residues Val209 and Val229. The analogous residue of ACVR2A, Ile83, is not predicted to fit into this pocket. C A zoom window shows Arg193 of DLK1 forming polar interactions with Thr93 and Glu94 of ACVR2B. The analogous residues in ACVR2A, Lys94 and Lys95, are not predicted to form charge complementary interactions. D–F Electrostatic potential surface representation of the DLK1-ACVR2B complex. The arrow indicates the ACVR2B interface glutamate (E94) residue that is substituted for a lysine (K95) in ACVR2A. D ACVR2B alone (E) and ACVR2A alone (F). G Sequence alignment of human ACVR2B and ACVR2A. Selected conserved (teal) and non-conserved (yellow) residues forming the DLK1-ACVR2B interface are highlighted. The E94 residue of ACVR2B is indicated with a black arrow.
