6o2q
Acetylated MicrotubulesAcetylated Microtubules
Structural highlights
Function[TBA1B_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. [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. Publication Abstract from PubMedAcetylation of K40 in alpha-tubulin is the sole posttranslational modification to mark the luminal surface of microtubules. It is still controversial whether its relationship with microtubule stabilization is correlative or causative. We have obtained high-resolution cryo-electron microscopy (cryo-EM) reconstructions of pure samples of alphaTAT1-acetylated and SIRT2-deacetylated microtubules to visualize the structural consequences of this modification and reveal its potential for influencing the larger assembly properties of microtubules. We modeled the conformational ensembles of the unmodified and acetylated states by using the experimental cryo-EM density as a structural restraint in molecular dynamics simulations. We found that acetylation alters the conformational landscape of the flexible loop that contains alphaK40. Modification of alphaK40 reduces the disorder of the loop and restricts the states that it samples. We propose that the change in conformational sampling that we describe, at a location very close to the lateral contacts site, is likely to affect microtubule stability and function. Effects of alpha-tubulin acetylation on microtubule structure and stability.,Eshun-Wilson L, Zhang R, Portran D, Nachury MV, Toso DB, Lohr T, Vendruscolo M, Bonomi M, Fraser JS, Nogales E Proc Natl Acad Sci U S A. 2019 May 21;116(21):10366-10371. doi:, 10.1073/pnas.1900441116. Epub 2019 May 9. PMID:31072936[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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