Integrins high-affinity conformation

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... 

Luo, B.-H., Takagi, J., and Springer, T. A. (2004b). Locking the f3i integrin I-like domain into high and low affinity conformations with disulfides. /. Biol. Chem. 279, 10215-10221. 

Figure 1 Movement of T lymphocytes from the blood into the lymph nodes, (a) Soluble or endothelial-displayed CCL21 ( ) binds CCR7 ( ). (b) The interaction induces a change in the conformation of the integrin tt4P7 from low affinity (I) to high affinity ( ). (c) The high affinity integrin then binds to mucosal addressin cell adhesion molecule-1, MAdCAM-1 (C), causing cell adhesion, (d) Directed cell migration between endothelial cells results.

---