Figure 5: Structural basis underlying regulation of ACF7 binding with F-actin by phosphorylation of tyrosine 259.
From: In vivo epidermal migration requires focal adhesion targeting of ACF7
(a) Structure of ACF7’s ABD. Note the closed conformation of the tandem CH domains, and interaction between Tyrosine 259 and the loop between CH1 and CH2 (green). (b) SAXS scattering curves of ACF7-NT and NT Y259D in PBS. The Guinier Rg was calculated using PRIMUS in ATSAS package. Note the highly similar scattering curves of NT and NT mutant in solution. (c) Detailed view of ACF7-NT structure (upper panel). Note the close contact of tyrosine 259 with the hinge sequence between CH1 and CH2, and formation of multiple hydrogen bonds between tyrosine 259 and residues in the loop (dashed lines). Lower panel indicates predicted structure of ACF7-NT on phosphorylation of tyrosine 259. The phosphorylation will likely disrupt the hydrogen bonds, and the negatively charged phosphate group is projected towards the hinge sequence, which contains multiple hydrophobic residues. (d) ACF7-NT or its various mutants were isolated from E. coli as His-tagged recombinant proteins. F-actin binding was examined by co-sedimentation assay. Pellet and supernatant as well as an aliquot of pre-cleared protein sample (input) were immunoblotted with α-His6 to determine F-actin binding affinity.
