The αβ tubulin heterodimer is the structural subunit of microtubules, which are cytoskeletal elements that are essential for intracellular transport and cell division in all eukaryotes. Each tubulin monomer binds a guanine nucleotide, which is non-exchangeable when it is bound in the α subunit, or N site, and exchangeable when bound in the β subunit, or E site. The α- and β-tubulins share 40% amino-acid sequence identity, both exist in several isotype forms, and both undergo a variety of post-translational modifications1. Limited sequence homology has been found with the proteins FtsZ2 and Misato3, which are involved in cell division in bacteria and Drosophila, respectively. Here we present an atomic model of the αβ tubulin dimer fitted to a 3.7-Å density map obtained by electron crystallography of zinc-induced tubulin sheets. The structures of α- and β-tubulin are basically identical: each monomer is formed by a core of two β-sheets surrounded by α-helices. The monomer structure is very compact, but can be divided into three functional domains: the amino-terminal domain containing the nucleotide-binding region, an intermediate domain containing the Taxol-binding site, and the carboxy-terminal domain, which probably constitutes the binding surface for motor proteins.
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Ludveña, R. F. The multiple forms of tubulin: different gene products and covalent modifications. Int. Rev. Cyt. 178, 207–275 (1998).
Mukherjee, A. & Lutkenhaus, J. Guanine nucleotide-dependent assembly of FtsZ into filaments. J.Bacteriol. 176, 2754–2758 (1994).
Gabor Miklos, G. L., Yamamoto, M., Burns, R. G. & Maleszka, R. An essential cell division gene of Drosophila, absent from Saccharomyces, encodes an unusual protein with tubulin-like and myosin-like peptide motifs. Proc. Natl Acad. Sci. USA 94, 5189–5194 (1997).
Nogales, E., Wolf, S. G., Zhang, S. X. & Downing, K. H. Preservation of 2-D crystals of tubulin for electron crystallography. J. Struct. Biol. 115, 199–208 (1995).
Nogales, E., Wolf, S. G., Khan, I. A., Ludueña, R. F. & Downing, K. H. Structure of tubulin at 6.5 Å and location of the taxol-binding site. Nature 375, 424–427 (1995).
Nogales, E., Wolf, S. G. & Downing, K. H. Visualizing the secondary structure of tubulin: three-dimensional map at 4 Å. J. Struct. Biol. 118, 119–127 (1997).
Burns, R. G. & Surridge, C. D. in Microtubules (eds Hyams, J. S. & Lloyd, C. W.) 3–32 (Wiley, New York, (1993)).
Little, M. & Ludueña, R. F. Structural differences between brain β1- and β2-tubulins: implications for microtubule assembly and colchicine binding. EMBO J. 4, 51–56 (1985).
Wolf, S. G., Nogales, E., Kikkawa, M., Gratzinger, D., Hirokawa, N. & Downing, K. H. Interpreting a medium-resolution model of tubulin: comparison of zinc-sheet and microtubule structure. J. Mol. Biol. 263, 485–501 (1996).
Shivanna, B. D., Mejillano, M. R., Williams, T. D. & Himes, R. H. Exchangeable GTP binding site of β-tubulin—identification of cysteine 12 as the major site of cross-linking by direct photoaffinity labeling. J. Biol. Chem. 268, 127–132 (1993).
Hesse, J., Thierauf, M. & Ponstingl, H. Tubulin sequence region β155–174 is involved in binding exchangeable guanosine triphosphate. J. Biol. Chem. 262, 15472–15475 (1987).
Linse, K. & Mandelkow, E.-M. The GTP-binding peptide of β-tubulin. Localization by direct photoaffinity labeling and comparison with nucleotide-binding proteins. J. Biol. Chem. 263, 15205–15210 (1988).
Davis, A., Sage, C. R., Dougherty, C. A. & Farrell, K. W. Microtubule dynamics modulated by guanosine triphosphate hydrolysis activity of β-tubulin. Science 264, 839–842 (1994).
Little, M. & Ludueña, R. F. Location of two cysteines in brain β1-tubulin that can be cross-linked after removal of exchangeable GTP. Biochim. Biophys. Acta 912, 28–33 (1987).
Bai, R. et al. Identification of cysteine 354 of β-tubulin as part of the binding site for the A ring of colchicine. J. Biol. Chem. 271, 12639–12645 (1996).
Uppuluri, S., Knipling, L., Sackett, D. L. & Wolff, J. Localization of the colchicine-binding site of tubulin. Proc. Natl Acad. Sci. USA 90, 11598–11602 (1993).
Shearwin, K. E. & Timasheff, S. N. Effect of colchicine analogs on the dissociation of αβ tubulin into subunits: the locus of colchicine binding. Biochemistry 33, 894–901 (1994).
Andreu, J. M. Site-directed antibodies to tubulin. Cell Motil. Cytoskel. 26, 1–6 (1993).
Caplow, M., Ruhlen, R. L. & Shanks, J. The free energy of hydrolysis of a microtubule-bound nucleoside triphosphate is near zero: all of the free energy for hydrolysis is stored in the microtubule lattice. J. Cell Biol. 127, 779–788 (1994).
Vale, R. D., Coppin, C. M., Malik, F., Kull, F. J. & Milligan, R. A. Tubulin GTP hydrolysis influences the structure, mechanical properties, and kinesin-driven transport of microtubules. J. Biol. Chem. 269, 23769–23775 (1994).
Hyman, A. A., Chrétien, D., Arnal, I. & Wade, R. H. Structural changes accompanying GTP hydrolysis of microtubules: information from a slowly hydrolyzable analog guanylyl-(α,β)-methylene-diphosphonate. J. Cell Biol. 128, 117–125 (1995).
Díaz, J. F., Pantos, E., Bordas, J. & Andreu, J. M. Solution structure of GDP-tubulin double rings to 3 nm resolution and comparison with microtubules. J. Mol. Biol. 238, 214–225 (1994).
Mandelkow, E. & Mandelkow, E.-M. Microtubules and microtubule-associated proteins. Curr. Opin. Cell Biol. 7, 72–81 (1995).
Gueritte-Voegelein, F. et al. Structure of a synthetic taxol precursor: N -tert-butoxycarbonyl-10-deacetyl-N -debenzoyltaxol. Acta Crystallogr. C 46, 781–784 (1990).
Rao, S., Krauss, N. E., Heerding, J. M., Orr, G. A. & Horwitz, S. B. 3′-(p -Azidobenzamido)taxol photolabels the N-terminal 31 amino acids of β-tubulin. J. Biol. Chem. 269, 3132–3134 (1994).
Rao, S., Orr, G. A., Chaudhary, A. G., Kingston, D. G. I. & Horwitz, S. B. Characterization of the taxol binding site on the microtubule. J. Biol. Chem. 270, 20235–20238 (1995).
Löwe, J. Y. & Amos, L. A. Crystal structure of the bacterial cell-division protein FtsZ complexed with GDP. Nature 391, 203–206 (1998).
Ponstingl, H., Krauhs, E., Little, M., Kempf, T., Hofer-Warbinek, R. & Ade, W. Amino acid sequence of α- and β-tubulins from pig brain: heterogeneity and regional similarity to muscle proteins. Cold Spring Harbor Symp. Quant. Biol. 46, 191–197 (1982).
Mitchison, T. J. Localization of an exchangeable GTP binding site at the plus end of microtubules. Science 261, 1044–1047 (1993).
Fan, J., Griffiths, A. D., Lockhart, A., Cross, R. A. & Amos, L. A. Microtubule minus ends can be labeled with a phage display antibody specific to α-tubulin. J. Mol. Biol. 259, 325–330 (1996).
We thank R. F. Ludueña for isotypically purified αβII and αβIII tubulin, M. Le for help with electron diffraction processing, and R. M. Glaeser and Y. L. Han for comments on the manuscript. Taxol was provided by the Drug Synthesis and Chemistry Branch, Division of Cancer Treatment of the National Cancer Institute. This work was supported by the NIH.
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Nogales, E., Wolf, S. & Downing, K. Structure of the αβ tubulin dimer by electron crystallography. Nature 391, 199–203 (1998). https://doi.org/10.1038/34465
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