Plant Cell Reports

, Volume 29, Issue 8, pp 927–933

Cytokinin and auxin regulates WUS induction and inflorescence regeneration in vitro in Arabidopsis

  • Zhi Juan Cheng
  • Shan Shan Zhu
  • Xin Qi Gao
  • Xian Sheng Zhang
Original Paper


Inflorescence regeneration in vitro provides a simplified approach for the study of inflorescence development. In this study, high frequency of regenerated inflorescences was established using Arabidopsis stage-10 pistil as the explants on the inducing medium containing the 2 mg/L zeatin and 0.01 mg/L indole-3-acetic acid. TERMINAL FLOWER 1 (TFL1) expression was detected in callus at 6 days after transferred to inducing medium, and LEAFY (LFY) expression was detectable subsequently, suggesting that both genes play important roles as they function on inflorescence development in the plant. To investigate the formation of the stem cell organizing center, we examined the WUSCHEL (WUS) and CLAVATA3 (CLV3) expression within callus during inflorescence regeneration. WUS signals start to accumulate on callus at 4 days after induction, and then, the CLV3 signals are induced on callus at 5 days on the inflorescence-inducing medium. The expression domain of WUS is below that of CLV3, indicating that the patterns of the organizing center and stem cell formation are similar to that in zygotic and somatic embryogenesis. However, more cells of the organizing center were observed within callus than pro-embryo, suggesting that inflorescence differentiation requires more cells of the organizing center. Furthermore, it was found that the WUS expression is controlled by the ratio of cytokinin with auxin. The results suggest that other factors besides WUS and CLV3 are required for inflorescence regeneration.


Hormone Inflorescence regeneration Stem cell organization center WUS expression 


  1. An YR, Li XG, Su HY, Zhang XS (2004) Pistil induction by hormones from the callus of Oryza sativa in vitro. Plant Cell Rep 23:448–452CrossRefPubMedGoogle Scholar
  2. Bradley D, Ratcliffe O, Vincent C, Carpenter R, Coen E (1997) Inflorescence commitment and architecture in Arabidopsis. Science 275:80–83CrossRefPubMedGoogle Scholar
  3. Conti L, Bradley D (2007) TERMINAL FLOWER1 is a mobile signal controlling Arabidopsis architecture. Plant Cell 19:767–778CrossRefPubMedGoogle Scholar
  4. Gordon SP, Heisler MG, Reddy GV, Ohno C, Das P, Meyerowitz EM (2007) Pattern formation during de novo assembly of the Arabidopsis shoot meristem. Development 134:3539–3548CrossRefPubMedGoogle Scholar
  5. Guan CM, Zhu SS, Li XG, Zhang XS (2006) Hormone-regulated inflorescence induction and TFL1 expression in Arabidopsis callus in vitro. Plant Cell Rep 25:1133–1137CrossRefPubMedGoogle Scholar
  6. Huala E, Sussex IM (1992) LEAFY interactes with floral homeotic genes to regulate Arabidopsis floral development. Plant Cell 4:901–903CrossRefPubMedGoogle Scholar
  7. Jack T (2004) Molecular and genetic mechanisms of floral control. Plant Cell 16:S1–S17CrossRefPubMedGoogle Scholar
  8. Laux T, Mayer KFX, Berger J, Jurgens G (1996) The WUSCHEL gene is required for shoot and floral meristem integrity in Arabidopsis. Development 122:87–96PubMedGoogle Scholar
  9. Li QZ, Li XG, Bai SN, Lu WL, Zhang XS (2002) Isolation of HAG1 and its regulation by plant hormones during in vitro floral organogenesis in Hyacinthus orientalis L. Planta 215:533–540CrossRefPubMedGoogle Scholar
  10. Mayer KF, Schoof H, Haecker A, Lenhard M, Jurgens G, Laux T (1998) Role of WUSCHEL in regulating stem cell fate in the Arabidopsis shoot meristem. Cell 95:805–815CrossRefPubMedGoogle Scholar
  11. Murashige T, Skoog F (1962) A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol Plant 5(3):473–497CrossRefGoogle Scholar
  12. Okada K, Ueda J, Komaki MK, Bell CJ, Shimura Y (1991) Requirement of the auxin polar transport system in early stages of Arabidopsis floral bud formation. Plant Cell 3:677–684CrossRefPubMedGoogle Scholar
  13. Scheres B (2007) Stem-cell niches: nursery rhymes across kingdoms. Nat Rev Mol Cell Biol 8:345–354CrossRefPubMedGoogle Scholar
  14. Schoof H, Lenhard M, Haecker A, Mayer KF, Jurgens G, Laux T (2000) The stem cell population of Arabidopsis shoot meristems in maintained by a regulatory loop between the CLAVATA and WUSCHEL genes. Cell 100:635–644CrossRefPubMedGoogle Scholar
  15. Shani E, Yanai O, Ori N (2006) The role of hormones in shoot apical meristem function. Curr Opin Plant Biol 9:484–489CrossRefPubMedGoogle Scholar
  16. Shannon S, Meeks-Wagner DR (1991) A mutation in the Arabidopsis TFL1 gene affects inflorescence meristem development. Plant Cell 3:877–892CrossRefPubMedGoogle Scholar
  17. Shimizu-Sato S, Tanaka M, Mori H (2009) Auxin–cytokinin interactions in the control of shoot branching. Plant Mol Biol 69:429–435CrossRefPubMedGoogle Scholar
  18. Skoog F, Miller CO (1957) Chemical regulation of growth and organ formation in plant tissues cultured in vitro. Symp Soc Exp Biol 11:118–131Google Scholar
  19. Smyth DR, Bowman JL, Meyerowitz EM (1990) Early flower development in Arabidopsis. Plant Cell 2:755–767CrossRefPubMedGoogle Scholar
  20. Su YH, Zhao XY, Liu YB, Zhang CL, O’Neill SD, Zhang XS (2009) Auxin-induced WUS expression is essential for embryonic stem cell renewal during somatic embryogenesis in Arabidopsis. Plant J 59:448–460CrossRefPubMedGoogle Scholar
  21. Tanaka H, Dhonukshe P, Brewer PB, Friml J (2006a) Spatiotemporal asymmetric auxin distribution: a means to coordinate plant development. Cell Mol Life Sci 63:2738–2754CrossRefPubMedGoogle Scholar
  22. Tanaka M, Takei K, Kojima M, Sakakibara H, Mori H (2006b) Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance. Plant J 45:1028–1036CrossRefPubMedGoogle Scholar
  23. Vieten A, Sauer M, Brewer PB, Friml J (2007) Molecular and cellular aspects of auxin-transport-mediated development. Trends Plant Sci 12:160–168CrossRefPubMedGoogle Scholar
  24. Wu BH, Zheng YL, Liu DC, Zhou YH, Yan ZH (2003) Unisexual pistillate flower regeneration in immature embryo culture of wheat. Acta Bot Sin 45:452–459Google Scholar
  25. Xu HY, Li XG, Li QZ, Bai SN, Lu WL, Zhang XS (2004) Characterization of HoMADS1 and its induction by plant hormones during in vitro development in Hyacinthus orientalis L. Plant Mol Biol 55:209–220CrossRefPubMedGoogle Scholar
  26. Xu YY, Wang XM, Li J, Li JH, Wu JS, Walker JC, Xu ZH, Chong K (2005) Activation of the WUS gene induces ectopic initiation of floral meristems on mature stem surface in Arabidopsis thaliana. Plant Mol Biol 57:773–784CrossRefPubMedGoogle Scholar
  27. Zhao Y (2008) The role of local biosynthesis of auxin and cytokinin in plant development. Curr Opin Plant Biol 11:16–22CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Zhi Juan Cheng
    • 1
  • Shan Shan Zhu
    • 1
  • Xin Qi Gao
    • 1
  • Xian Sheng Zhang
    • 1
  1. 1.State Key Laboratory of Crop Biology, College of Life SciencesShandong Agricultural UniversityTaianChina

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