Integrins bent conformation

Fig. 3. Conformational states for integrins. A-C. Model for a l3 integrin activation, with at least three conformations of the extracellular domain (Takagi et al, 2002). (A) Bent, low affinity conformation. (B) Extended conformation with closed headpiece. (C) Extended conformation with open headpiece shown with bound RGD-mimetic peptide (green CPK). D-H. Model for aiJ3 integrin activation. (D) Bent conformation with low affinity. (E) and (F) with a closed headpiece and closed I domain in...

In solution and apparently on the cell surface as well, integrins are not fixed in a particular conformation, but equilibrate between them (Takagi et al, 2002) (Fig. 3A-G). Whether the equilibrium favors the bent, low affinity conformation or the extended, high affinity conformation is affected by the presence of activating intracellular factors and the... 

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