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.
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Borkird, C.; Choi, J. H.; Jin, Z., et al. Developmental regulation of embryonic genes in plant. Proc. Natl. Acad. Sci. USA 85:6399–6403; 1988.
Chen, J.; Varner, J. E. Isolation and characterization of cDNA clones for carrot extension and a proline-rich 33-kDa protein. Proc. Natl. Acad. Sci. USA 82:4399–4403; 1985.
Chibbar, R. N.; Polowick, P. L.; Newsted, W. J., et al. Identification and isolation of a unique esterase from the medium of non-embryogenic cell line of cultured carrot cells. Plant Cell Tissue Organ Cult. 18:47–53; 1989.
Choi, J. H.; Liu, L. S.; Borkird, C., et al. Isolation of cDNA clones for rare embryo-specific antigens in carrot cell cultures. Proc. Natl. Acad. Sci. USA 84:1906–1910; 1987.
Franz, G.; Hatzopoulos, P.; Jones, T. J., et al. Molecular and genetic analysis of an embryogenic gene, DC 8, fromDaucus carota L. Mol. Gen. Genet. 218:143–151; 1989.
Fujimura, T.; Komamine, A. Synchronization of somatic embryogenesis in a carrot cell suspension culture. Plant Physiol. 64:162–164; 1979.
Fujimura, T.; Komamine, A. The serial observation of embryogenesis in a carrot cell suspension culture. New Phytol. 86:213–218; 1980.
Fujimura, T.; Komamine, A. Involvement of endogenous auxin in somatic embryogenesis in a carrot cell suspension culture. Z. Pflanzenphysiol. 95:13–19; 1979.
Fujimura, T.; Komamine, A. Effects of growth regulators on embryogenesis in a carrot suspension culture. Plant. Sci. Lett. 5:359–364; 1975.
Hong, J. C.; Nagao, R. T.; Key, J. L., et al. Characterization and sequence analysis of a developmentally regulated putative cell wall protein gene isolated from soybean. J. Biol. Chem. 262:8367–8376; 1987.
Lo Schiavo, F. L.; Giuliano, G.; Sung, Z. R. Characterization of a temperature-sensitive carrot cell mutant impaired in somatic embryogenesis. Plant. Sci. 54:157–164; 1988.
Nomura, K.; Komamine, A. Identification and isolation of single cells that produce somatic embryos at a high frequency in a carrot suspension culture. Plant Physiol. 79:988–991; 1985.
Reinert, J. Untersuchungen uber die Morphogenese an Gewebekulturen. Ber. Dtsch. Bot. Ges. 71:15; 1958.
Smith, J. A.; Krauss, M. R.; Borkird, C., et al. A nuclear protein associated with cell divisions in plants. Planta 174:462–472; 1988.
Steward, F. C.; Mapes, M. O.; Mears, K. Growth and organized development of cultured cells. II. Organization in cultures grown from freely suspended cells. Am. J. Bot. 45:705–708; 1958.
Sung, Z. R.; Okimoto, R. Embryonic proteins in somatic embryos of carrot. Proc. Natl. Acad. Sci. USA 78:3683–3687; 1981.
Sung, Z. R.; Okimoto, R. Coordinate gene expression during somatic embryogenesis in carrot. Proc. Natl. Acad. Sci. USA 80:2661–2665; 1983.
Wilde, H. D.; Nelson, W. S.; Booij, H., et al. Gene-expression programs in embryogenic and non-embryogenic carrot cultures. Planta 176:205–211; 1988.
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Presented in the Session-in-Depth Developmental Biology of Embryogenesis at the 1991 World Congress on Cell and Tissue Culture, Anaheim, California, June 16–20, 1991.
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Komamine, A., Kawahara, R., Matsumoto, M. et al. Mechanisms of somatic embryogenesis in cell cultures: Physiology, biochemistry, and molecular biology. In Vitro Cell Dev Biol - Plant 28, 11–14 (1992). https://doi.org/10.1007/BF02632185
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DOI: https://doi.org/10.1007/BF02632185