Chimeric genes and transgenic plants are used to study the regulation of genes involved in symbiotic plant-microbe interactions (nodulin genes)

Authors

  • Frans J. de Bruijn,

    Corresponding author
    1. Max-Planck-Institut für Züchtungsforschung, 5 Köln 30, Federal Republic of Germany
    2. MSU-DOE Plant Research Laboratory and Department of Microbiology and Public Health, Michigan State University, East Lansing, USA
    • MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
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  • Laszló Szabados,

    1. Max-Planck-Institut für Züchtungsforschung, 5 Köln 30, Federal Republic of Germany
    Current affiliation:
    1. Biological Research Center, Institute of Plant Physiology, P.O. Box 521, H 6701-Szeged, Hungary
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  • Jeff Schell

    1. Max-Planck-Institut für Züchtungsforschung, 5 Köln 30, Federal Republic of Germany
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Abstract

Nodulin genes are plant genes specifically activated during the formation of nitrogen-fixing nodules on leguminous plants. These genes are interesting to study since they are not only induced in a specific developmental fashion by signals coming directly or indirectly from the rhizobial symbiont, but are also expressed in a tissue-specific manner. By examining the expression of chimeric nodulin-reporter genes in transgenic legume plants it has been shown that nodule specific expression is mediated by DNA sequences present in the 5′upstream region of several nodulin genes. Here we summarize the available data on these cis-acting elements and the trans-acting factors interacting with them. We also review experiments designed to identify rhizobial “signals” which may play a role in nodule specific gene expression.

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