Fig. 7: Structural basis of the CH domain release from the bMERB domain upon Rab8a binding.
From: The mechanism of activation of the actin binding protein EHBP1 by Rab8 family members
a Structural superposition of the EHBP1 bMERBH1-2:CH domain and EHBP1 bMERBM1116A:GppNHp Rab8a1-176 complexes. b, c Schematic presentation of the CH (green, N-terminal) and Rab8 (blue, C-terminal) binding site of EHBP1 bMERB domain. Structural and sequence alignment of the N-and C-terminal halves of the EHBP1 bMERB domain, showing strong conservation between both CH and Rab8a binding sites. CH and Rab8a interacting residues are shown in red. * denotes critical residues for the interaction. d Structural alignment of the EHBP1 CH domain (orange, bMERB binding site (bMERB_BS) in blue) with the filamin A CH1 domain (gray). F-actin binding sites in the filamin A CH1 domain are shown in pink (ABS-N), red (ABS2´), and in green (ABS2). (ABS actin binding site). e Structural model of the F-actin:EHBP1 CH domain complex, based on the complex structure of filamin A CH1 domain:F-actin (PDB ID 6D8C). The bMERB binding site (bMERB_BS, blue) of the CH domain is buried by the actin filament.
