Leukemia-Associated Mutations in Nucleophosmin Alter Recognition by CRM1: Molecular Basis of Aberrant Transport
Fig 6
Analysis of importin α/β/NPM interaction by SEC and ITC.
(A) Elution profiles of mixtures of 10 μM (pentamer) NPM with 70 μM importin Δα (red) or 70 μM importin α and 140 μM importin β (blue), and mixture of 70 μM importin α and 140 μM importin β (green). The control of 10 μM NPM (black) is also shown. The complexes are saturated, as evidenced by the absence of free NPM, and excess of free importins. Importin β was always added in molar excess to avoid the presence of free importin α, which also binds NPM, although with lower affinity. (B) Titration of importin α/β (21 μM) onto NPM (7.2 μM pentamer) (top panel) and fit of the binding isotherm by an independent binding sites model (bottom panel), with a χ2 / DoF of 3.22 x 106.