5IJ0

Cryo EM density of microtubule assembled from human TUBB3

Summary for 5IJ0

• Entry DOI: 10.2210/pdb5ij0/pdb
• Related: 5IJ9
• EMDB information: 8094 8095
• Descriptor: Tubulin alpha-1B chain, Tubulin beta-3 chain, GUANOSINE-5'-TRIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: human, microtubules, tubulin, hydrolysis, structural protein
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 2
• Total formula weight: 97465.64

Authors

Ti, S.-C.,Pamula, M.C.,Howes, S.C.,Duellberg, C.,Nicholas, C.I.,Kleiner, R.E.,Forth, S.,Surrey, T.,Nogales, E.,Kapoor, T.M. (deposition date: 2016-03-01, release date: 2016-04-20, Last modification date: 2024-03-06)

Primary citation

Ti, S.C.,Pamula, M.C.,Howes, S.C.,Duellberg, C.,Cade, N.I.,Kleiner, R.E.,Forth, S.,Surrey, T.,Nogales, E.,Kapoor, T.M.
Mutations in Human Tubulin Proximal to the Kinesin-Binding Site Alter Dynamic Instability at Microtubule Plus- and Minus-Ends.
Dev.Cell, 37:72-84, 2016

PubMed Abstract: The assembly of microtubule-based cellular structures depends on regulated tubulin polymerization and directional transport. Here, we purify and characterize tubulin heterodimers that have human β-tubulin isotype III (TUBB3), as well as heterodimers with one of two β-tubulin mutations (D417H or R262H). Both point mutations are proximal to the kinesin-binding site and have been linked to an ocular motility disorder in humans. Compared to wild-type, microtubules with these mutations have decreased catastrophe frequencies and increased average lifetimes of plus- and minus-end-stabilizing caps. Importantly, the D417H mutation does not alter microtubule lattice structure or Mal3 binding to growing filaments. Instead, this mutation reduces the affinity of tubulin for TOG domains and colchicine, suggesting that the distribution of tubulin heterodimer conformations is changed. Together, our findings reveal how residues on the surface of microtubules, distal from the GTP-hydrolysis site and inter-subunit contacts, can alter polymerization dynamics at the plus- and minus-ends of microtubules.

PubMed: 27046833
DOI: 10.1016/j.devcel.2016.03.003

Experimental method

ELECTRON MICROSCOPY (3.8 Å)