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Mechanisms of somatic embryogenesis in cell cultures: Physiology, biochemistry, and molecular biology

  • A. Komamine
  • R. Kawahara
  • M. Matsumoto
  • S. Sunabori
  • T. Toya
  • A. Fujiwara
  • M. Tsukahara
  • J. Smith
  • M. Ito
  • H. Fukuda
  • K. Nomura
  • T. Fujimura
Regular Papers

Summary

One of the most characteristic cell functions in plants is totipotency. Somatic embryogenesis can be regarded as a model system for the investigation of mechanisms of totipotency, because a high frequency and synchronous embryogenic system from single somatic cells has been established in carrot suspension cultures. Four phases are recognized in this process, and several molecular markers, viz. polypeptides, mRNAs, antigens against monoclonal antibodies, can be detected during the expression of totipotency, but they disappear during its loss. Four organ-specific genes have been isolated from hypocotyls and roots by differential screening. They were expressed preferentially after the globular-heart stages of embryogenesis, and were strongly suppressed by auxin. A CEM 1 gene was isolated by differential screening of embryogenic cell clusters. This gene was expressed strongly and transiently during the proglobular and globular stages. The sequence of CEM 1 was found to encode a polypeptide showing high homology to the elongation factor isolated from eucaryotic cells. Thus good progress is being made in understanding the basic mechanisms of somatic embryogenesis.

Key words

carrot elongation factor gene expression polarity somatic embryogenesis totipotency 

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Copyright information

© Tissue Culture Association 1992

Authors and Affiliations

  • A. Komamine
    • 1
  • R. Kawahara
    • 1
  • M. Matsumoto
    • 1
  • S. Sunabori
    • 1
  • T. Toya
    • 1
  • A. Fujiwara
    • 1
  • M. Tsukahara
    • 1
  • J. Smith
    • 1
  • M. Ito
    • 1
  • H. Fukuda
    • 1
  • K. Nomura
    • 1
  • T. Fujimura
    • 1
  1. 1.Biological InstituteTohoku UniversitySendaiJapan

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