Abstract
We describe here a new α-tubulin isoform from sunflower we named απ-tubulin. απ-tubulin is the most divergent higher-plant α-tubulin described so far, having an unusual deletion in the H1/B2 loop and a glutamine-rich C-terminus. We constructed a three-dimensional model and discuss its implications. Using specific antibodies, we show that απ-tubulin expression is restricted to the male gametophyte. απ-tubulin mRNA represents 90% of α-tubulin mRNA and a small percentage of total pollen mRNA. Among the plants tested, απ-tubulin was only detected in sunflower and in Cosmos. Since both plants are Asteraceae, we propose that απ-tubulin is specific to this family. Our results suggest that απ-tubulin can inhibit tubulin assembly in pollen. This hypothesis is reinforced by the fact that απ-tubulin is found in a complex with β-tubulin in mature sunflower pollen.
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References
Azimzadeh, J., Traas, J. and Pastuglia, M. 2001. Molecular aspects of microtubule dynamics in plants. Curr. Opin. Plant Biol. 4: 513–519.
Bao, Y., Kost, B. and Chua, N.H. 2001. Reduced expression of ?-tubulin genes in Arabidopsis thaliana specifically affects root growth and morphology, root hair development and root gravitropism. Plant J. 28: 145–157.
Berman, H.M., Westbrook, J., Feng, Z., Gilliland, G., Bhat, T.N., Weissig, H., Shindyalov, I.N. and Bourne, P.E. 2000. The Protein Data Bank. Nucl. Acids Res. 28: 235–242.
Bichet, A., Desnos, T., Turner, S., Grandjean, O. and Höfte, H. 2001. BOTERO1 is required for normal orientation of cortical microtubules and anisotropic cell expansion in Arabidopsis. Plant J. 25: 137–148.
Canaday, J., Stoppin-Mellet, V., Mutterer, J., Lambert, A.M. and Schmit, A.C. 2000. Higher plant cells: ?-tubulin andmicrotubule nucleation in the absence of centrosomes. Microsc. Res. Tech. 49: 487–495.
Carpenter, J.L., Ploense, S.E., Snustad, D.P. and Silflow, C.D. 1992. Preferential expression of an ?-tubulin gene of Arabidopsis in pollen. Plant Cell 4: 557–571.
Carpenter, J.L., Kopczak, S.D., Snustad, D.P. and Silflow, C.D. 1993. Semi-constitutive expression of an Arabidopsis thaliana ?-tubulin gene. Plant Mol. Biol. 21: 937–942.
Cyr, R.J. and Palevitz, B.A. 1995. Organization of cortical microtubules in plant cells. Curr. Opin. Cell Biol. 7: 65–71.
Derksen, J., Pierson, E.S. and Traas, J.A. 1985. Microtubules in vegetative and generative cells of pollen tubes. Eur. J. Cell Biol. 38: 142–148.
Dutcher, S.K. 2001. The tubulin fraternity: alpha to eta. Curr. Opin. Cell Biol. 13: 49–54.
Endlé, M.C., Stoppin, V., Lambert, A.M. and Schmit, A.C. 1998. The growing cell plate of higher plants is a site of both actin assembly and vinculin-like antigen recruitment. Eur. J. Cell Biol. 77: 10–18.
Feng, Y., Hodge, D.R., Palmieri, G., Chase, D.L., Longo, D.L. and Ferris, D.K. 1999. Association of polo-like kinase with ?-, ?-and ?-tubulins in a stable complex. Biochem. J. 339: 435–442.
Fosket, D.E. and Morejohn, L.C. 1992. Structural and functional organization of tubulin. Annu. Rev. Plant Physiol. Plant Mol. Biol. 43: 201–240.
Geissler, S., Siegers, K. and Schiebel, E. 1998. A novel protein complex promoting formation of functionnal ? and ? tubulin. EMBO J. 17: 952–966.
Heese, M., Mayer, U. and Jürgens, G. 1998. Cytokinesis in flowering plants: cellular process and developmental integration. Curr. Opin. Plant Biol. 1: 486–491.
Heslop-Harrison, J., Heslop-Harrison, Y., Cresti, M., Tiezzi, A. and Moscatelli, A. 1988. Cytoskeletal elements, cell shaping and movement in the angiosperm pollen-tube. J. Cell Sci. 91: 49–60.
Keating, T.J. and Borisy, G.G. 2000. Immunostructural evidence for the template mechanism of microtubule nucleation. Nature Cell Biol. 2: 352–357.
Kopczak, S.D., Haas, N.A., Hussey, P.J., Silflow, C.D. and Snustad, D.P. 1992. The small genome of Arabidopsis contains at least six expressed ?-tubulin genes. Plant Cell 4: 539–547.
Kost, B., Mathur, J. and Chua, N.M. 1999. Cytoskeleton in plant development. Curr. Opin. Plant Biol. 2: 462–470.
Mascarenhas, J.P. 1990. Gene activity during pollen development. Annu. Rev. Plant Physiol. Plant Mol. Biol. 41: 317–338.
Meurer-Grob, P., Kasparian, J. and Wade, R.H. 2001. Microtubule structure at improved resolution. Biochemistry 40: 8000–8008.
Moritz, M. and Agard, D.A. 2001. ?-Tubulin complexes and microtubule nucleation. Curr. Opin. Struct. Biol. 11: 174–181.
Nogales, E. 1999. A structural view of microtubule dynamics. Cell Mol. Life Sci. 56: 133–142.
Nogales, E., Wolf, S. G. and Downing, K. H. 1998. Structure of the ?? tubulin dimer by electron crystallography. Nature 391: 199–203.
Nogales, E., Whittaker, M., Milligan, R.A. and Downing, K.H. 1999. High-resolution model of the microtubule. Cell 96: 79–88.
Pierson, E.S. and Cresti, M. 1992. Cytoskeleton and cytoplasmic organization of pollen and pollen tubes. Int. Rev. Cytol. 140: 73–125.
Pratt, L.F., Okamura, S. and Cleveland, D.W. 1987. A divergent testis-specific ?-tubulin isotype that does not contain a coded Cterminal tyrosine. Mol. Cell Biol. 7: 552–555.
Sali A. and Blundell T.L. 1993. Comparative protein modelling by satisfaction of spatial restraints. J. Mol. Biol. 234: 779–815.
Smith, L.G. 1999. Divide and conquer: cytokinesis in plant cells. Curr. Opin. Plant Biol. 2: 447–453.
Snustad, D.P., Haas, N.A., Kopczak, S.D. and Silflow, C.D. 1992. The small genome of Arabidopsis contains at least nine expressed ?-tubulin genes. Plant Cell. 4: 549–556.
Stoppin-Mellet, V., Peter, C. and Lambert, A.M. 2000. Distribution of ?-tubulin in higher plant cells: cytosolic ?-tubulin is part of high molecular weight complexes. Plant Biol. 2: 290–296.
Taylor, P.E.. and Hepler, P.K. 1997. Pollen germination and tube growth. Annu. Rev. Plant Physiol. Plant Mol. Biol. 48: 461–491.
Tiwari, S.C. and Polito, V.S. 1988. Spatial and temporal organization of actin during hydration, activation, and germination of pollen in Pyrus communis L. A. Protoplasma 147: 5–15.
Vantard, M., Stoppin, V. and Lambert, A.M. 1998. Cell cycle dependent nucleation and assembly of plant microtubular proteins. In: D. Francis, D. Dudits and D. Enzi (Eds.) Plant Cell Division, Portland Press, pp. 301-318.
Wick, S. 2000. Plant microtubules meet their MAPs and mimics. Nature Cell Biol. 2: 204–206.
Wilson, P.G. and Borisy G.G. 1997. Evolution of the multi-tubulin hypothesis. BioEssays 19: 451–454.
Wymer, C. and Lloyd, C. 1996. Dynamic microtubules: implications for cell wall patterns. Trends Plant Sci. 1: 222–228.
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Evrard, JL., Nguyen, I., Bergdoll, M. et al. A novel pollen-specific α-tubulin in sunflower: structure and characterization. Plant Mol Biol 49, 611–620 (2002). https://doi.org/10.1023/A:1015545916961
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DOI: https://doi.org/10.1023/A:1015545916961