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5hnz is a 3 chain structure with sequence from Bos taurus and Drome. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[TBA1B_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain. [NCD_DROME] NCD is required for normal chromosomal segregation in meiosis, in females, and in early mitotic divisions of the embryo. The NCD motor activity is directed toward the microtubule's minus end.[1] [TBB2B_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity).
Publication Abstract from PubMed
Kinesin-14 is a unique minus-end-directed microtubule-based motor. A swinging motion of a class-specific N-terminal neck helix has been proposed to produce minus-end directionality. However, it is unclear how swinging of the neck helix is driven by ATP hydrolysis utilizing the highly conserved catalytic core among all kinesins. Here, using a motility assay, we show that in addition to the neck helix, the conserved five residues at the C-terminal region in kinesin-14, namely the neck mimic, are necessary to give kinesin-1 an ability to reverse its directionality toward the minus end of microtubules. Our structural analyses further demonstrate that the C-terminal neck mimic, in cooperation with conformational changes in the catalytic core during ATP binding, forms a kinesin-14 bundle with the N-terminal neck helix to swing toward the minus end of microtubules. Thus, the neck mimic plays a crucial role in coupling the chemical ATPase reaction with the mechanical cycle to produce the minus-end-directed motility of kinesin-14.
Structural Basis of Backwards Motion in Kinesin-1-Kinesin-14 Chimera: Implication for Kinesin-14 Motility.,Yamagishi M, Shigematsu H, Yokoyama T, Kikkawa M, Sugawa M, Aoki M, Shirouzu M, Yajima J, Nitta R Structure. 2016 Aug 2;24(8):1322-34. doi: 10.1016/j.str.2016.05.021. Epub 2016, Jul 21. PMID:27452403[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Walker RA, Salmon ED, Endow SA. The Drosophila claret segregation protein is a minus-end directed motor molecule. Nature. 1990 Oct 25;347(6295):780-2. PMID:2146510 doi:http://dx.doi.org/10.1038/347780a0
↑ Yamagishi M, Shigematsu H, Yokoyama T, Kikkawa M, Sugawa M, Aoki M, Shirouzu M, Yajima J, Nitta R. Structural Basis of Backwards Motion in Kinesin-1-Kinesin-14 Chimera: Implication for Kinesin-14 Motility. Structure. 2016 Aug 2;24(8):1322-34. doi: 10.1016/j.str.2016.05.021. Epub 2016, Jul 21. PMID:27452403 doi:http://dx.doi.org/10.1016/j.str.2016.05.021
