Bishop Cleo L, Purton Saul, Nugent Jonathan H A
Photosynthesis Research Group, Department of Biology, Darwin Building, University College London, Gower Street, London WC1E 6BT, UK.
Plant Mol Biol. 2003 May;52(2):285-9. doi: 10.1023/a:1023963113290.
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.
PsbW是一种定位于叶绿体类囊体膜的核编码蛋白。在高等植物中的研究提供了大量证据表明PsbW是光系统II的核心组分。然而,最近有数据表明PsbW也是光系统I的一个亚基。两个光系统之间亚基的这种共享将代表一种新现象。为了对此进行研究,我们从绿藻莱茵衣藻中克隆并鉴定了psbW基因。该基因被5个内含子分割,编码一个由115个残基组成的多肽,其中包括6.1 kDa的成熟PsbW蛋白,其前面有一个59个氨基酸的双功能转运序列。我们使用针对PsbW产生的抗体检测了:(1)缺乏任一光系统的莱茵衣藻突变体,以及(2)纯化的光系统制剂。我们发现PsbW是光系统II的一个亚基,而不是光系统I的亚基。