If you need an accessible version of this item please contact JSTOR User Support

psbA in the Marine Chromophyte Heterosigma carterae: Evolutionary Analysis and Comparative Structure of the D1 Carboxyl Terminus

Linda K. Hardison, Barbara A. Boczar and Rose Ann Cattolico
American Journal of Botany
Vol. 82, No. 7 (Jul., 1995), pp. 893-902
Stable URL: http://www.jstor.org/stable/2445976
Page Count: 10
  • Download PDF
  • Cite this Item

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support
psbA in the Marine Chromophyte Heterosigma carterae: Evolutionary Analysis and Comparative Structure of the D1 Carboxyl Terminus
Preview not available

Abstract

The 32 kDa D1 protein, encoded by the psbA gene, is a component of photosystem II in photosynthetic eukaryotes and cyanobacteria. In the chl a,c-containing alga Heterosigma carterae (previously referred to as Olisthodiscus luteus), psbA is transcribed as a 1.7-kb monocistronic message. The transcription start site and putative prokaryotic-like -10 (TATAAT) and -35 (GTGATT) promoter domains have been identified for this gene, which encodes a protein that is 360 amino acids in length. The protein contains a seven amino acid motif near the carboxyl terminus that is also present in non-chl b-containing algal plastids and cyanobacteria, but not in terrestrial plants, green algae, or the prokaryote Prochlorothrix. Phylogenetic analysis of D1 sequences, with special attention to the seven amino acid motif, suggests that plastids of rhodophytic and chromophytic algae form an evolutionary lineage distinct from cyanobacteria and chlorophytic (chl a,b-containing) chloroplasts. A model for the function of the seven amino acid motif is proposed.

Page Thumbnails

  • Thumbnail: Page 
893
    893
  • Thumbnail: Page 
894
    894
  • Thumbnail: Page 
895
    895
  • Thumbnail: Page 
896
    896
  • Thumbnail: Page 
897
    897
  • Thumbnail: Page 
898
    898
  • Thumbnail: Page 
899
    899
  • Thumbnail: Page 
900
    900
  • Thumbnail: Page 
901
    901
  • Thumbnail: Page 
902
    902