Watanabe Mai, Iwai Masako, Narikawa Rei, Ikeuchi Masahiko
Department of Life Sciences (Biology), Graduate School of Arts and Science, University of Tokyo, Meguro, Tokyo, Japan.
Plant Cell Physiol. 2009 Sep;50(9):1674-80. doi: 10.1093/pcp/pcp112. Epub 2009 Aug 10.
It is widely believed that the photosystem II (PSII) complex may function as a dimer in the thylakoid membrane. Here, we report experimental conversion from the monomeric PSII to the dimeric form by treatment with high concentrations of n-dodecyl-beta-D-maltopyranoside (DM). The content of the PSII monomer in a PsbTc deletion mutant was much higher than in the wild type when solubilized with low concentrations of DM. However, upon treatment with higher concentrations of DM, the PSII dimer was also recovered in the PsbTc deletion mutant. These results suggest that there are at least two distinct processes of dimerization: (i) PsbTc dependent and (ii) DM induced. We discuss the results with regard to the native assembly form(s) of PSII.
人们普遍认为，光系统II（PSII）复合物在类囊体膜中可能以二聚体形式发挥作用。在此，我们报告了通过用高浓度的正十二烷基-β-D-麦芽糖苷（DM）处理，将单体PSII实验性转化为二聚体形式。当用低浓度的DM溶解时，PsbTc缺失突变体中PSII单体的含量比野生型高得多。然而，在用更高浓度的DM处理后，PsbTc缺失突变体中也恢复了PSII二聚体。这些结果表明，至少存在两种不同的二聚化过程：（i）依赖于PsbTc的过程和（ii）DM诱导的过程。我们就PSII的天然组装形式讨论了这些结果。
