Laboratoire d'Ecologie Végétale, Université Paris-Sud, URA 1492, Bât. 362, 91403, Orsay Cedex, France.
Photosynth Res. 1994 Jun;40(3):287-94. doi: 10.1007/BF00034778.
Recently, it has been suggested (Horton et al. 1992) that aggregation of the light-harvesting a-b complex (LHC II) in vitro reflects the processes which occur in vivo during fluorescence induction and related to the major non-photochemical quenching (qE). Therefore the requirement of this chlorophyll a-b containing protein complex to produce qN was investigated by comparison of two barley mutants either lacking (chlorina f2) or depressed (chlorina(104)) in LHC II to the wild-type and pea leaves submitted to intermittent light (IL) and during their greening in continuous light.It was observed that qN was photoinduced in the absence of LHC II, i.e. in IL grown pea leaves and the barley mutants. Nevertheless, in these leaves qN had no (IL, peas) or little (barley mutants) inhibitory effect on the photochemical efficiency of QA reduction measured by flash dosage response curves of the chlorophyll fluorescence yield increase induced by a single turn-over flashDuring greening in continuous light of IL pea leaves, an inhibitory effect on QA photoreduction associated to qN developed as Photosystem II antenna size increased with LHC II synthesis. Utilizing data from the literature on connectivity between PS II units versus antenna size, the following hypothesis is put forward to explain the results summarized above. qN can occur in the core antenna or Reaction Center of a fraction of PS II units and these units will not exhibit variable fluorescence. Other PS II units are quenched indirectly through PS II-PS II exciton transfer which develops as the proportion of connected PS II units increases through LHC II synthesis.
最近，有人提出（Horton 等人，1992），在体外聚集光捕获 a-b 复合物（LHC II）反映了在荧光诱导和相关的主要非光化学猝灭（qE）过程中体内发生的过程。因此，通过比较两种大麦突变体（缺乏（chlorina f2）或减少（chlorina(104))）与野生型和豌豆叶片，研究了这种含有叶绿素 a-b 的蛋白质复合物产生 qN 的要求，这些叶片在间歇光（IL）下和连续光的变绿过程中。观察到 qN 在没有 LHC II 的情况下被光诱导，即在 IL 生长的豌豆叶片和大麦突变体中。然而，在这些叶片中，qN 对 QA 还原的光化学效率没有（IL，豌豆）或很少（大麦突变体）的抑制作用，这是通过单翻转闪光诱导的叶绿素荧光产额增加的闪光剂量响应曲线测量的。在 IL 豌豆叶片的连续光下变绿时，与 qN 相关的 QA 光还原的抑制作用随着 LHC II 合成的增加而发展。利用 PS II 单位与天线大小之间的连接性的文献数据，提出了以下假设来解释上述总结的结果。qN 可以在 PS II 单位的核心天线或反应中心的一部分中发生，这些单位不会表现出可变荧光。其他 PS II 单位通过 LHC II 合成增加的连接 PS II 单位的比例，通过 PS II-PS II 激子转移间接猝灭。
