Nuclear Encoding of a Chloroplast RNA Polymerase Sigma Subunit in a Red Alga
Nuclear Encoding of a Chloroplast RNA Polymerase Sigma Subunit in a Red Alga
复制标题
红藻叶绿体 RNA 聚合酶 Sigma 亚基的核编码
作者：
Kan Tanaka;Kosuke Oikawa;N. Ohta;H. Kuroiwa;T. Kuroiwa;H. Takahashi
叶绿体RNA聚合酶西格玛因子是由红藻蓝藻RK-1中的核基因SigA编码的。编码的蛋白质在体外起RNA聚合酶西格玛因子的作用，在体内定位于叶绿体。SIgA与蓝藻的Sigma因子有很高的序列相似性，这预示着祖先的内生共生事件以及随后SIGA基因向核基因组的转移。
A chloroplast RNA polymerase sigma factor is encoded by a nuclear gene, sigA, in the red alga Cyanidium caldarium RK-1. The encoded protein functions as an RNA polymerase sigma factor in vitro and it is localized to the chloroplast in vivo. SigA shows high sequence similarity to the sigma factors of cyanobacteria, which is indicative of the ancestral endosymbiotic event and subsequent transfer of the sigA gene to the nuclear genome.