2owm
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| , resolution 3.25Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , , , , , , and | ||||||
| Ligands: | and | ||||||
| Gene: | 17E5.250 (Neurospora crassa) | ||||||
| Activity: | Plus-end-directed kinesin ATPase, with EC number 3.6.4.4 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Motor domain of Neurospora crassa kinesin-3 (NcKin3)
OverviewOverview
Neurospora crassa kinesin NcKin3 belongs to a unique fungal-specific subgroup of small Kinesin-3-related motor proteins. One of its functions appears to be the transport of mitochondria along microtubules. Here, we present the X-ray structure of a C-terminally truncated monomeric construct of NcKin3 comprising the motor domain and the neck linker, and a 3-D image reconstruction of this motor domain bound to microtubules, by cryoelectron microscopy. The protein contains Mg.ADP bound to the active site, yet the structure resembles an ATP-bound state. By comparison with structures of the Kinesin-3 motor Kif1A in different nucleotide states (Kikkawa, M. et al. (2001) Nature (London, U.K.) 411, 439-445), the NcKin3 structure corresponds to the AMPPCP complex of Kif1A rather than the AMPPNP complex. NcKin3-specific differences in the coordination of the nucleotide and asymmetric interactions between adjacent molecules in the crystal are discussed in the context of the unusual kinetics of the dimeric wild-type motor and the monomeric construct used for crystal structure analysis. The NcKin3 motor decorates microtubules at a stoichiometry of one head per alphabeta-tubulin heterodimer, thereby forming an axial periodicity of 8 nm. In spite of unusual extensions at the N-terminus and within flexible loops L2, L8a, and L12 (corresponding to the K-loop of monomeric kinesins), the microtubule binding geometry is similar to that of other members of the kinesin family.
About this StructureAbout this Structure
2OWM is a Single protein structure of sequence from Neurospora crassa. Full crystallographic information is available from OCA.
ReferenceReference
X-ray Structure and Microtubule Interaction of the Motor Domain of Neurospora crassa NcKin3, a Kinesin with Unusual Processivity(,)., Marx A, Muller J, Mandelkow EM, Woehlke G, Bouchet-Marquis C, Hoenger A, Mandelkow E, Biochemistry. 2008 Feb 19;47(7):1848-1861. Epub 2008 Jan 19. PMID:18205396
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