Plant Molecular Biology

, Volume 52, Issue 2, pp 285–289 | Cite as

Molecular analysis of the Chlamydomonas nuclear gene encoding PsbW and demonstration that PsbW is a subunit of photosystem II, but not photosystem I

  • Cleo L. Bishop
  • Saul Purton
  • Jonathan H.A. NugentEmail author


PsbW is a nuclear-encoded protein located in the thylakoid membrane of the chloroplast. Studies in higher plants have provided substantial evidence that PsbW is a core component of photosystem II. However, recent data have been presented to suggest that PsbW is also a subunit of photosystem I. Such a sharing of subunits between the two photosystems would represent a novel phenomenon. To investigate this, we have cloned and characterized the psbW gene from the green alga Chlamydomonas reinhardtii. The gene is split by five introns and encodes a polypeptide of 115 residues comprising the 6.1 kDa mature PsbW protein preceded by a 59 amino acid bipartite transit sequence. Using antibodies raised to PsbW we have examined: (1) C. reinhardtii mutants lacking either photosystem and (2) purified photosystem preparations. We find that PsbW is a subunit of photosystem II, but not photosystem I.

Chlamydomonas photosystem I photosystem II PsbW subunit psbW 


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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Cleo L. Bishop
    • 1
  • Saul Purton
    • 1
  • Jonathan H.A. Nugent
    • 1
    Email author
  1. 1.Photosynthesis Research Group, Department of Biology, Darwin BuildingUniversity College LondonLondonUK

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