4U3J

TOG2:alpha/beta-tubulin complex

Summary for 4U3J

• Entry DOI: 10.2210/pdb4u3j/pdb
• Descriptor: Tubulin alpha-1 chain, Tubulin beta chain, Protein STU2, ... (6 entities in total)
• Functional Keywords: complex, structural protein-protein binding complex, structural protein/protein binding
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Total number of polymer chains: 3
• Total formula weight: 131686.74

Authors

Ayaz, P.,Rice, L.M. (deposition date: 2014-07-22, release date: 2014-08-20, Last modification date: 2023-09-27)

Primary citation

Ayaz, P.,Munyoki, S.,Geyer, E.A.,Piedra, F.A.,Vu, E.S.,Bromberg, R.,Otwinowski, Z.,Grishin, N.V.,Brautigam, C.A.,Rice, L.M.
A tethered delivery mechanism explains the catalytic action of a microtubule polymerase.
Elife, 3:e03069-e03069, 2014

PubMed Abstract: Stu2p/XMAP215 proteins are essential microtubule polymerases that use multiple αβ-tubulin-interacting TOG domains to bind microtubule plus ends and catalyze fast microtubule growth. We report here the structure of the TOG2 domain from Stu2p bound to yeast αβ-tubulin. Like TOG1, TOG2 binds selectively to a fully 'curved' conformation of αβ-tubulin, incompatible with a microtubule lattice. We also show that TOG1-TOG2 binds non-cooperatively to two αβ-tubulins. Preferential interactions between TOGs and fully curved αβ-tubulin that cannot exist elsewhere in the microtubule explain how these polymerases localize to the extreme microtubule end. We propose that these polymerases promote elongation because their linked TOG domains concentrate unpolymerized αβ-tubulin near curved subunits already bound at the microtubule end. This tethering model can explain catalyst-like behavior and also predicts that the polymerase action changes the configuration of the microtubule end.

PubMed: 25097237
DOI: 10.7554/eLife.03069

Experimental method

X-RAY DIFFRACTION (2.81 Å)