Journal of Plant Research

, Volume 121, Issue 5, pp 493–498 | Cite as

Transient increase in the transcript levels of γ-tubulin complex genes during reorientation of cortical microtubules by gravity in azuki bean (Vigna angularis) epicotyls

  • Kouichi SogaEmail author
  • Toshihisa Kotake
  • Kazuyuki Wakabayashi
  • Seiichiro Kamisaka
  • Takayuki Hoson
Short Communication


By hypergravity treatment, the percentage of cells with transverse microtubules was decreased, while that with longitudinal microtubules was increased in azuki bean (Vigna angularis) epicotyls. The expression of genes encoding γ-tubulin complex (VaTUG and VaGCP3) was increased transiently in response to changes in the gravitational conditions. Lanthanum and gadolinium ions, potential blockers of mechanosensitive calcium ion-permeable channels (mechanoreceptors), nullified reorientation of microtubules as well as up-regulation of expression of VaTUG and VaGCP3 by hypergravity. These results suggest that mechanoreceptors may perceive the gravity signal, which leads to a transient increase in the transcript levels of γ-tubulin complex genes and reorientation of cortical microtubules.


Azuki bean (Vigna angularis Ohwi et Ohashi) Epicotyl Gravity Microtubule γ-Tubulin complex 



We thank Professor H. Numata of Osaka City University for his advice on statistical analysis. The present study was supported in part by Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology, a Grant for Ground-based Research for Space Utilization from the Japan Space Forum, and by Sasakawa Scientific Research Grant from the Japan Science Society.


  1. Baskin TI (2001) On the alignment of cellulose microfibrils by cortical microtubules: a review and a model. Protoplasma 215:150–171PubMedCrossRefGoogle Scholar
  2. Ding JP, Pickard BG (1993) Mechanosensory calcium-selective cation channels in epidermal cells. Plant J 3:83–110CrossRefGoogle Scholar
  3. Erhardt M, Stoppin-Mellet V, Campagne S, Canaday J, Mutterer J, Fabian T, Sauter M, Muller T, Peter C, Lambert AM, Schmit AC (2002) The plant Spc98p homologue colocalizes with γ-tubulin at microtubule nucleation sites and is required for microtubule nucleation. J Cell Sci 115:2423–2431PubMedGoogle Scholar
  4. Fasano JM, Massa GD, Gilroy S (2002) Ionic signaling in plant responses to gravity and touch. J Plant Growth Regul 21:71–88PubMedCrossRefGoogle Scholar
  5. Giddings TH, Staehelin LA (1991) Microtubule-mediated control of microfibril deposition: a re-examination of the hypothesis. In: Lloyd CW (ed) The cytoskeletal basis of plant growth and form. Academic Press, London, pp 85–97Google Scholar
  6. Hoson T, Nishitani K, Miyamoto K, Ueda J, Kamisaka S, Yamamoto R, Masuda Y (1996) Effects of hypergravity on growth and cell wall properties of cress hypocotyls. J Exp Bot 47:513–517PubMedCrossRefGoogle Scholar
  7. Hoson T, Soga K, Mori R, Saiki M, Nakamura Y, Wakabayashi K, Kamisaka S (2002) Stimulation of elongation growth and cell wall loosening in rice coleoptiles under microgravity conditions in space. Plant Cell Physiol 43:1067–1071PubMedCrossRefGoogle Scholar
  8. Kasahara H, Shiwa M, Takeuchi Y, Yamada M (1995) Effects of hypergravity on elongation growth in radish and cucumber hypocotyls. J Plant Res 108:59–64PubMedCrossRefGoogle Scholar
  9. Matsumoto S, Saito Y, Kumasaki S, Soga K, Wakabayashi K, Hoson T (2007) Up-regulation of expression of tubulin genes and roles of microtubules in hypergravity-induced growth modification in Arabidopsis hypocotyls. Adv Space Res 39:1176–1181CrossRefGoogle Scholar
  10. Murata T, Sonobe S, Baskin TI, Hyodo S, Hasezawa S, Nagata T, Horio T, Hasebe M (2005) Microtubule-dependent microtubule nucleation based on recruitment of gamma-tubulin in higher plants. Nature Cell Biol 7:961–968PubMedCrossRefGoogle Scholar
  11. Pastuglia M, Azimzadeh J, Goussot M, Camilleri C, Belcram K, Evrard JL, Schmit AC, Guerche P, Bouchez D (2006) γ-Tubulin is essential for microtubule organization and development in Arabidopsis. Plant Cell 18:1412–1425PubMedCrossRefGoogle Scholar
  12. Raynaud-Messina B, Merdes A (2007) γ-Tubulin complexes and microtubule organization. Curr Opin Cell Biol 19:24–30PubMedCrossRefGoogle Scholar
  13. Roberts IN, Lloyd CW, Roberts K (1985) Ethylene-induced microtubule reorientations: mediation by helical arrays. Planta 164:439–447CrossRefGoogle Scholar
  14. Shibaoka H (1994) Plant hormone-induced changes in the orientation of cortical microtubules: alterations in the cross-linking between microtubules and the plasma membrane. Ann Rev Plant Physiol Plant Mol Biol 45:527–544Google Scholar
  15. Skagen EB, Iversen TH (1999) Simulated weightlessness and hyper-g results in opposite effects on the regeneration of the cortical microtubule array in protoplasts from Brassica napus hypocotyls. Physiol Plant 106:318–325PubMedCrossRefGoogle Scholar
  16. Smith LG, Oppenheimer DG (2005) Spatial control of cell expansion by the plant cytoskeleton. Ann Rev Cell Develop Biol 21:271–295CrossRefGoogle Scholar
  17. Soga K, Wakabayashi K, Hoson T, Kamisaka S (1999a) Hypergravity increases the molecular size of xyloglucans by decreasing xyloglucan-degrading activity in azuki bean epicotyls. Plant Cell Physiol 40:581–585PubMedGoogle Scholar
  18. Soga K, Harada K, Wakabayashi K, Hoson T, Kamisaka S (1999b) Increased molecular mass of hemicellulosic polysaccharides is involved in growth inhibition of maize coleoptiles and mesocotyls under hypergravity conditions. J Plant Res 112:273–278PubMedCrossRefGoogle Scholar
  19. Soga K, Wakabayashi K, Kamisaka S, Hoson T (2002) Stimulation of elongation growth and xyloglucan breakdown in Arabidopsis hypocotyls under microgravity conditions in space. Planta 215:1040–1046PubMedCrossRefGoogle Scholar
  20. Soga K, Wakabayashi K, Kamisaka S, Hoson T (2004) Graviperception in growth inhibition of plant shoots under hypergravity conditions produced by centrifugation is independent of that in gravitropism and may involve mechanoreceptors. Planta 218:1054–1061PubMedCrossRefGoogle Scholar
  21. Soga K, Wakabayashi K, Kamisaka S, Hoson T (2005) Mechanoreceptors rather than sedimentable amyloplasts perceive the gravity signal in hypergravity-induced inhibition of root growth in azuki bean. Funct Plant Biol 32:175–179PubMedCrossRefGoogle Scholar
  22. Soga K, Wakabayashi K, Kamisaka S, Hoson T (2006) Hypergravity induces reorientation of cortical microtubules and modifies growth anisotropy in azuki bean epicotyls. Planta 224:1485–1494PubMedCrossRefGoogle Scholar
  23. Toyota M, Furuichi T, Tatsumi H, Sokabe M (2007) Hypergravity stimulation induces changes in intracellular calcium concentration in Arabidopsis seedlings. Adv Space Res 39:1190–1197CrossRefGoogle Scholar
  24. Waldron KW, Brett CT (1990) Effects of extreme acceleration on the germination, growth and cell wall composition of pea epicotyls. J Exp Bot 41:71–77CrossRefGoogle Scholar
  25. Wasteneys GO (2004) Progress in understanding the role of microtubules in plant cells. Curr Opin Plant Biol 7:651–660PubMedCrossRefGoogle Scholar
  26. Wymer CL, Wymer SA, Cosgrove DJ, Cyr RJ (1996) Plant cell responds to external forces and the response requires intact microtubules. Plant Physiol 110:425–430PubMedGoogle Scholar

Copyright information

© The Botanical Society of Japan and Springer 2008

Authors and Affiliations

  • Kouichi Soga
    • 1
    Email author
  • Toshihisa Kotake
    • 2
  • Kazuyuki Wakabayashi
    • 1
  • Seiichiro Kamisaka
    • 3
  • Takayuki Hoson
    • 1
  1. 1.Department of Biology and Geosciences, Graduate School of ScienceOsaka City UniversityOsakaJapan
  2. 2.Division of Life Science, Graduate School of Science and EngineeringSaitama UniversitySaitamaJapan
  3. 3.Graduate School of Science and EngineeringUniversity of ToyamaToyamaJapan

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