3jar

Cryo-EM structure of GDP-microtubule co-polymerized with EB3Cryo-EM structure of GDP-microtubule co-polymerized with EB3

3jar, resolution 3.50Å Show:Asymmetric Unit Biological Assembly Structural highlights 3jar is a 14 chain structure with sequence from Human and Sus scrofa. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: Related: 3jak, 3jal, 3jas, 3jat Gene: MAPRE3 (HUMAN) Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT 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. [MARE3_HUMAN] Binds to the plus end of microtubules and regulates the dynamics of the microtubule cytoskeleton. Promotes microtubule growth. May be involved in spindle function by stabilizing microtubules and anchoring them at centrosomes. May play a role in cell migration (By similarity). [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 PubMed Microtubule (MT) dynamic instability is driven by GTP hydrolysis and regulated by microtubule-associated proteins, including the plus-end tracking end-binding protein (EB) family. We report six cryo-electron microscopy (cryo-EM) structures of MTs, at 3.5 A or better resolution, bound to GMPCPP, GTPgammaS, or GDP, either decorated with kinesin motor domain after polymerization or copolymerized with EB3. Subtle changes around the E-site nucleotide during hydrolysis trigger conformational changes in alpha-tubulin around an "anchor point," leading to global lattice rearrangements and strain generation. Unlike the extended lattice of the GMPCPP-MT, the EB3-bound GTPgammaS-MT has a compacted lattice that differs in lattice twist from that of the also compacted GDP-MT. These results and the observation that EB3 promotes rapid hydrolysis of GMPCPP suggest that EB proteins modulate structural transitions at growing MT ends by recognizing and promoting an intermediate state generated during GTP hydrolysis. Our findings explain both EBs end-tracking behavior and their effect on microtubule dynamics. Mechanistic Origin of Microtubule Dynamic Instability and Its Modulation by EB Proteins.,Zhang R, Alushin GM, Brown A, Nogales E Cell. 2015 Jul 28. pii: S0092-8674(15)00849-1. doi: 10.1016/j.cell.2015.07.012. PMID:26234155 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.