Integrins are α/β heterodimers that interconvert between inactive and active states. In the active state the α/β cytoplasmic domains recruit integrin-activating proteins and separate the transmembrane and cytoplasmic (TMcyto) domains (unclasped TMcyto). Conversely, in the inactive state the α/β TMcyto domains bind integrin-inactivating proteins, resulting in the association of the TMcyto domains (clasped TMcyto). Here, we report the isolation of integrin cytoplasmic tail interactors using either lipid bicelle-incorporated integrin TMcyto domains (α5, αM, αIIb, β1, β2 and β3 integrin TMcyto) or a clasped, lipid bicelle-incorporated αMβ2 TMcyto. Among the proteins found to preferentially bind clasped rather than the isolated αM and β2 subunits was L-plastin (LCP1, also known as plastin-2), which binds to and maintains the inactive state of αMβ2 integrin in vivo and thereby regulates leukocyte adhesion to integrin ligands under flow. Our findings offer a global view on cytoplasmic proteins interacting with different integrins and provide evidence for the existence of conformation-specific integrin interactors.
CITATION STYLE
Tseng, H. Y., Samarelli, A. V., Kammerer, P., Scholze, S., Ziegler, T., Immler, R., … Böttcher, R. T. (2018). LCP1 preferentially binds clasped αMβ2 integrin and attenuates leukocyte adhesion under flow. Journal of Cell Science, 131(22). https://doi.org/10.1242/jcs.218214
Mendeley helps you to discover research relevant for your work.