TABLE 1.
Summary of binding data showing that the kinesin-1 tail-microtubule interaction is electrostatic in nature, and is mediated by the basic residues in the 892–914 region of the tail and the acidic E-hooks of tubulin (αβ = wild-type microtubules, αsβs = subtilisin-treated microtubules)
See Figs. 1, supplemental S1A, S2B, and S3 for microtubule co-sedimentation and fluorescence anisotropy experiments. All dissociation constants are reported as the mean ± S.E. for three experiments
| Ligand | Microtubule |
Kd |
|
|---|---|---|---|
| Microtubule co-sedimentation | Fluorescence anisotropy | ||
| μm | |||
| Tail944 | αβ | 0.45 ± 0.15 | |
| Tail944 R907C-F | αβ | 0.65 ± 0.21 | 0.46 ± 0.02 |
| Tail963 R907C-F | αβ | 0.56 ± 0.12 | 0.51 ± 0.07 |
| Tail944 A905C-F | αβ | 0.65 ± 0.14 | 0.35 ± 0.03 |
| Tail944 A905C-F Mutant A | αβ | 12.5 ± 2.2 | NDa |
| Tail944 A905C-F Mutant B | αβ | 3.8 ± 1.4 | ND |
| Tail944 A905C-F Mutant A+B | αβ | 16.7 ± 7.1 | ND |
| Tail944 R907C-F | αsβs | 4.06 ± 2.9 | 3.17 ± 0.36 |
a ND, not determined.