Matsuzaki Motomichi, Misumi Osami, Shin-I Tadasu, Maruyama Shinichiro, Takahara Manabu, Miyagishima Shin-Ya, Mori Toshiyuki, Nishida Keiji, Yagisawa Fumi, Nishida Keishin, Yoshida Yamato, Nishimura Yoshiki, Nakao Shunsuke, Kobayashi Tamaki, Momoyama Yu, Higashiyama Tetsuya, Minoda Ayumi, Sano Masako, Nomoto Hisayo, Oishi Kazuko, Hayashi Hiroko, Ohta Fumiko, Nishizaka Satoko, Haga Shinobu, Miura Sachiko, Morishita Tomomi, Kabeya Yukihiro, Terasawa Kimihiro, Suzuki Yutaka, Ishii Yasuyuki, Asakawa Shuichi, Takano Hiroyoshi, Ohta Niji, Kuroiwa Haruko, Tanaka Kan, Shimizu Nobuyoshi, Sugano Sumio, Sato Naoki, Nozaki Hisayoshi, Ogasawara Naotake, Kohara Yuji, Kuroiwa Tsuneyoshi
Department of Biomedical Chemistry, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Nature. 2004 Apr 8;428(6983):653-7. doi: 10.1038/nature02398.
Small, compact genomes of ultrasmall unicellular algae provide information on the basic and essential genes that support the lives of photosynthetic eukaryotes, including higher plants. Here we report the 16,520,305-base-pair sequence of the 20 chromosomes of the unicellular red alga Cyanidioschyzon merolae 10D as the first complete algal genome. We identified 5,331 genes in total, of which at least 86.3% were expressed. Unique characteristics of this genomic structure include: a lack of introns in all but 26 genes; only three copies of ribosomal DNA units that maintain the nucleolus; and two dynamin genes that are involved only in the division of mitochondria and plastids. The conserved mosaic origin of Calvin cycle enzymes in this red alga and in green plants supports the hypothesis of the existence of single primary plastid endosymbiosis. The lack of a myosin gene, in addition to the unexpressed actin gene, suggests a simpler system of cytokinesis. These results indicate that the C. merolae genome provides a model system with a simple gene composition for studying the origin, evolution and fundamental mechanisms of eukaryotic cells.
超小单细胞藻类的小型紧凑基因组提供了有关支持包括高等植物在内的光合真核生物生命的基本和必需基因的信息。在此，我们报告单细胞红藻嗜热栖热放线菌10D的20条染色体的16,520,305碱基对序列，这是首个完整的藻类基因组。我们总共鉴定出5331个基因，其中至少86.3%表达。这种基因组结构的独特特征包括：除26个基因外所有基因均无内含子；仅三个核糖体DNA单元拷贝维持核仁；以及两个仅参与线粒体和质体分裂的发动蛋白基因。这种红藻和绿色植物中卡尔文循环酶保守的镶嵌起源支持了单一原始质体内共生存在的假说。除未表达的肌动蛋白基因外缺乏肌球蛋白基因，表明胞质分裂系统更简单。这些结果表明，嗜热栖热放线菌基因组为研究真核细胞的起源、进化和基本机制提供了一个基因组成简单的模型系统。
