Planta

, Volume 206, Issue 2, pp 204–214

Characterization of rbcS genes in the fern Pteris vittata and their photoregulation

  • Haviva Eilenberg
  • Uri Hanania
  • Hanan Stein
  • Aviah Zilberstein
Article

DOI: 10.1007/s004250050392

Cite this article as:
Eilenberg, H., Hanania, U., Stein, H. et al. Planta (1998) 206: 204. doi:10.1007/s004250050392

Abstract.

The fern Pteris vittata L. belongs to the evolutionarily highest group of vascular plants that still maintains a free-living gametophytic stage. The two-dimensional gametophytes developed under blue light exhibit higher CO2 fixation efficiency and different ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) small subunit (SSU) composition when compared to the red-induced filamentous gametophytes (H. Eilenberg et al., 1991, Plant Physiol 95: 298–304). To unravel the correlation between SSU structural differences and light regulation, two rbcS genes and two additional partial cDNAs were characterized. Fern rbcS genes resemble those of higher plants in their promoter light-regulatory elements (LREs) and intron number and positions. However, the primary structure of the fern mature SSUs displays much higher divergency within the gene family. This structural variability was correlated with differential steady-state mRNA levels under red and blue light. Genes rbcS-1 and -4 show 4- to 6-fold higher transcript levels in red light while rbcS-2 and -3 contribute relatively more to the blue rbcS mRNA levels. Five of the 12 amino acids that differ between rbcS-2 and -4 affect hydrophobicity and might play a crucial role in determining the efficiency of CO2 fixation. Dendrograms of Rubisco SSUs and LSUs indicate early divergence of the fern types from the rest of the vascular plants. However, prominent higher-plant-like Rubisco features such as high carboxylation efficiency, promoter LREs and exon-intron structure, suggest that molecular specialization of the higher-plant Rubisco prototype occurred earlier than the emergence of ferns.

Key words: FernPhotoregulation (rbcS)Pteris (rbcS regulation)rbcSRibulose 15-bisphosphate carboxylase/oxygenase

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Haviva Eilenberg
    • 1
  • Uri Hanania
    • 1
  • Hanan Stein
    • 1
  • Aviah Zilberstein
    • 1
  1. 1.Department of Plant Sciences, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, 69978 Tel Aviv, IsraelIL