Plant Molecular Biology

, Volume 39, Issue 3, pp 503–514

Structure of two maize phytase genes and their spatio-temporal expression during seedling development

  • Sébastien Maugenest
  • Isabelle Martinez
  • Béatrice Godin
  • Pascual Perez
  • Anne-Marie Lescure
Article

DOI: 10.1023/A:1006131506193

Cite this article as:
Maugenest, S., Martinez, I., Godin, B. et al. Plant Mol Biol (1999) 39: 503. doi:10.1023/A:1006131506193

Abstract

Up to 80% of Zea mays L. grain phosphorus is stored in the form of phytin in the embryo. Our objective is to determine the control of phytin mobilization during germination and seedling growth. A maize phytase cDNA, phy S11, has been previously characterized (Maugenest et al., Biochem J 322: 511–517, 1997). In the present work, phy S11 was used to screen a maize genomic library and two distinct genes, PHYT I and PHYT II, were isolated and sequenced. The transcribed sequences of these two genes presented a strong homology whereas the untranscribed upstream and downstream sequences appeared very different. Northern blot analysis and in situ hybridization showed a high accumulation of phytase mRNA at the early steps of germination in the coleorhiza, radicle cortex and coleoptile parenchyma. Phytase expression was also detected at a lower extent in the scutellum. In adult plants, northern blot analyses revealed low but significant levels of phytase mRNA in the roots. In situ hybridizations on root cross-sections localized phytase mRNA in rhizodermis, endodermis and pericycle layers. Immunolocalization analysis showed phytase accumulation at the same sites as its mRNA. A RT-PCR approach was used in an attempt to discriminate between the transcripts from each gene in the different situations. These experiments indicate that both genes are expressed during germination, whereas only PHYT I is expressed in adult roots. This suggests that signals responsible for phytase gene expression in roots are different from those responsible for gene expression during germination.

Zea mays L.seedling phytasegenomic sequencesspatio-temporal gene expression

Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  • Sébastien Maugenest
    • 1
  • Isabelle Martinez
    • 2
  • Béatrice Godin
    • 1
  • Pascual Perez
    • 2
  • Anne-Marie Lescure
    • 1
  1. 1.Laboratoire de Biologie des Semences, INRA INA-PGVersailles CédexFrance
  2. 2.BIOCEM-Groupe LimagrainAubière CédexFrance