Molecular Plant Biology, Department of Biochemistry, University of Turku, Turku, Finland.
Umeå University, Faculty of Science and Technology, Department of Plant Physiology, Umeå Plant Science Centre (UPSC), Umeå, Sweden.
J Exp Bot. 2019 Jun 28;70(12):3211-3225. doi: 10.1093/jxb/erz127.
Pinaceae are the predominant photosynthetic species in boreal forests, but so far no detailed description of the protein components of the photosynthetic apparatus of these gymnosperms has been available. In this study we report a detailed characterization of the thylakoid photosynthetic machinery of Norway spruce (Picea abies (L.) Karst). We first customized a spruce thylakoid protein database from translated transcript sequences combined with existing protein sequences derived from gene models, which enabled reliable tandem mass spectrometry identification of P. abies thylakoid proteins from two-dimensional large pore blue-native/SDS-PAGE. This allowed a direct comparison of the two-dimensional protein map of thylakoid protein complexes from P. abies with the model angiosperm Arabidopsis thaliana. Although the subunit composition of P. abies core PSI and PSII complexes is largely similar to that of Arabidopsis, there was a high abundance of a smaller PSI subcomplex, closely resembling the assembly intermediate PSI* complex. In addition, the evolutionary distribution of light-harvesting complex (LHC) family members of Pinaceae was compared in silico with other land plants, revealing that P. abies and other Pinaceae (also Gnetaceae and Welwitschiaceae) have lost LHCB4, but retained LHCB8 (formerly called LHCB4.3). The findings reported here show the composition of the photosynthetic apparatus of P. abies and other Pinaceae members to be unique among land plants.
松科植物是北方森林中主要的光合物种，但迄今为止，这些裸子植物光合作用器官的蛋白质成分还没有详细的描述。在这项研究中，我们详细描述了挪威云杉（Picea abies (L.) Karst）的类囊体光合机制。我们首先从翻译的转录序列和现有的基因模型衍生的蛋白质序列组合定制了一个云杉类囊体蛋白质数据库，这使得能够从二维大孔蓝色-native/SDS-PAGE 可靠地鉴定 P. abies 类囊体蛋白的串联质谱。这使得能够直接比较来自 P. abies 的类囊体蛋白复合物的二维蛋白质图谱与模式被子植物拟南芥。尽管 P. abies 核心 PSI 和 PSII 复合物的亚基组成在很大程度上与拟南芥相似，但存在大量较小的 PSI 亚复合物，与组装中间 PSI*复合物非常相似。此外，通过计算机比较了松柏科植物的光捕获复合物（LHC）家族成员的进化分布与其他陆地植物，结果表明，P. abies 和其他松柏科植物（也包括买麻藤科和百岁兰科）失去了 LHCB4，但保留了 LHCB8（以前称为 LHCB4.3）。这里报道的发现表明，P. abies 和其他松柏科成员的光合作用器官的组成在陆地植物中是独特的。
