Table I. Rates of nuclear import of wild-type and mutant FKHR.

Mutation	Mean cytoplasmic concentration (arbitrary units)	Initial rate of import (U/min)
Wild type	37 ± 3	0.20 ± 0.02
Thr24Ala	28 ± 4	0.22 ± 0.05
Ser256Ala	16 ± 1	0.24 ± 0.02
Ser319Ala	28 ± 2	0.17 ± 0.03
Ser322Ala	35 ± 4	0.12 ± 0.03
Ser329Ala	34 ± 3	0.23 ± 0.04
Ser319Ala, Ser322Ala,     Ser325Ala, Ser329Ala	29 ± 4	0.17 ± 0.02

FKHR–GFP was transfected as described in the legend of Figure 8. After serum starvation for 2 h, and pre-incubation with leptomycin B (5 ng/ml) for 20 min, rates of nuclear import were determined in the presence of IGF-1 and 10% serum as described in Materials and methods.