条斑紫菜光系统Ⅱ反应中心蛋白编码psbA和psbD的表达分析

Expression analysis of psbA and psbD genes of Porphyra yezoensis in different developmental stages

从条斑紫菜(Porphyra yezoensisUeda)的3个不同的生长阶段:壳孢子、孢子体和配子体中提取总RNA,并用相应基因的引物扩增序列,用荧光定量PCR技术检测条斑紫菜3个生长阶段中psbA和psbD的转录水平变化。结果表明,psbA和psbD的变化趋势不一致,并且,在壳孢子内基因表达量相对较高。这说明在细胞内,D1蛋白和D2蛋白并非同比例合成。壳孢子成熟发育成叶状体的过程要求光合作用提供更多的能量。

Proteins D1 and D2, respectively encoded by psbA and psbD genes, comprise the PSⅡ reaction center. They are correlative with PSⅡ activity, which is affected by light intensity and temperature. In this study, transcription changes of psbA and psbD genes in three different growth phases of Porphyra yezoensis-conchospores, sporophytes and gametophytes were determined with real-time PCR. The results showed that psbA expression changes were different from psbD expression changes, indicating the variation of D1 protein and D2 protein synthesis. Both of the gene expressions were relatively high in conchospores, which may be due to the higher requirement of energy provided by photosynthesis in conchospores than in gametophytes.