Plant Molecular Biology

, Volume 16, Issue 2, pp 199–207

The combination of a novel stimulatory element in the first exon of the maize Shrunken-1 gene with the following intron 1 enhances reporter gene expression up to 1000-fold


  • Christoph Maas
    • Institut für Genetik der Universität zu Köln
  • Jürgen Laufs
    • Max-Planck Institüt für Züchtungsforschung
  • Sarah Grant
    • Max-Planck Institüt für Züchtungsforschung
  • Christian Korfhage
    • Institut für Genetik der Universität zu Köln
  • Wolfgang Werr
    • Institut für Genetik der Universität zu Köln

DOI: 10.1007/BF00020552

Cite this article as:
Maas, C., Laufs, J., Grant, S. et al. Plant Mol Biol (1991) 16: 199. doi:10.1007/BF00020552


Both exon 1 and intron 1 of the maize Shrunken-1 (Sh1) gene individually stimulate expression of reporter genes in transient gene expression experiments if present within the transcription unit. The Sh1 exon 1 mediates a 10-fold increase in activity when inserted at the 5′ end of the bacterial chloramphenicol transacetylase (CAT) marker gene in both monocot and dicot protoplasts. The Sh1 intron 1 enhances chimeric gene expression in rice and maize protoplasts approximately 100-fold but inhibits CAT expression in tobacco protoplasts. In combination, the stimulatory effects of Sh1 exon 1 and intron 1 are multiplicative in monocot protoplasts resulting in a final enhancement of up to 1000-fold compared to the unmodified CAT or luciferase marker genes.

Key words

enhanced gene expressionexonintronmaizerice

Copyright information

© Kluwer Academic Publishers 1991