Structural highlights
Function
[DYHC_DICDI] Cytoplasmic dynein acts as a motor for the intracellular retrograde motility of vesicles and organelles along microtubules. Dynein has ATPase activity; the force-producing power stroke is thought to occur on release of ADP. [TBB_PIG] 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. [TBA1A_PIG] 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.
Publication Abstract from PubMed
Dynein is a motor protein that moves on microtubules (MTs) using the energy of adenosine triphosphate (ATP) hydrolysis. To understand its motility mechanism, it is crucial to know how the signal of MT binding is transmitted to the ATPase domain to enhance ATP hydrolysis. However, the molecular basis of signal transmission at the dynein-MT interface remains unclear. Scanning mutagenesis of tubulin identified two residues in alpha-tubulin, R403 and E416, that are critical for ATPase activation and directional movement of dynein. Electron cryomicroscopy and biochemical analyses revealed that these residues form salt bridges with the residues in the dynein MT-binding domain (MTBD) that work in concert to induce registry change in the stalk coiled coil and activate the ATPase. The R403-E3390 salt bridge functions as a switch for this mechanism because of its reversed charge relative to other residues at the interface. This study unveils the structural basis for coupling between MT binding and ATPase activation and implicates the MTBD in the control of directional movement.
A flipped ion pair at the dynein-microtubule interface is critical for dynein motility and ATPase activation.,Uchimura S, Fujii T, Takazaki H, Ayukawa R, Nishikawa Y, Minoura I, Hachikubo Y, Kurisu G, Sutoh K, Kon T, Namba K, Muto E J Cell Biol. 2015 Jan 19;208(2):211-22. doi: 10.1083/jcb.201407039. Epub 2015 Jan, 12. PMID:25583999[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Uchimura S, Fujii T, Takazaki H, Ayukawa R, Nishikawa Y, Minoura I, Hachikubo Y, Kurisu G, Sutoh K, Kon T, Namba K, Muto E. A flipped ion pair at the dynein-microtubule interface is critical for dynein motility and ATPase activation. J Cell Biol. 2015 Jan 19;208(2):211-22. doi: 10.1083/jcb.201407039. Epub 2015 Jan, 12. PMID:25583999 doi:http://dx.doi.org/10.1083/jcb.201407039
