Regulation of Rubisco operon in red algal lineage

在进化过程中，祖先质体起源于单一的内共生，并通过整合到真核细胞中而失去了自主性。然而，转录因子 Ycf30 保留在目前已知的红藻和灰藻谱系的质体基因组中。此前，我们提出了Ycf30通过感测光合代谢物响应环境变化而建立的Rubisco操纵子转录激活模型。在本报告中，为了在体内测试该模型，我们分析了响应环境变化的代谢物。从高CO2条件转向空调期间，3-PGA和RuBP特别积累。这个结果与之前提出的模型一致。 Ycf30 感知光合代谢物积累的变化，并激活 Rubisco 操纵子的转录以响应环境变化。红藻质体转录因子代表了祖先质体自主性的最后遗迹。

During evolution, ancestral plastids arose from a single endosymbiosis and have lost their autonomy through integration into the eukaryotic cell. However, a transcription factor, Ycf30 is retained in currently known plastid genomes of red algal and Glaucophyte lineages. Previously, we suggested transcriptional activation model of Rubisco operon by Ycf30 through sensing of photosynthetic metabolites in response to the environmental changes.In this report, to test the model in vivo, we analyzed metabolites in response to the environmental changes. During the shift from high CO2 condition to air condition, 3-PGA and RuBP were specially accumulated. This result is agreed with the model suggested previously. Ycf30 senses the change in the accumulations of photosynthetic metabolites and activates the transcription of Rubisco operon in response to the environmental changes. Red algal plastidial transcription factors represent the last relics of the autonomy of the ancestral plastid.