Genome sequence of the ultrasmall unicellular red alga Cyanidioschyzon merolae 10D.
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.
Matsuzaki
Motomichi
M
Department of Biomedical Chemistry, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. mzaki@biol.s.u-tokyo.ac.jp
Misumi
Osami
O
Shin-I
Tadasu
T
Maruyama
Shinichiro
S
Takahara
Manabu
M
Miyagishima
Shin-Ya
SY
Mori
Toshiyuki
T
Nishida
Keiji
K
Yagisawa
Fumi
F
Nishida
Keishin
K
Yoshida
Yamato
Y
Nishimura
Yoshiki
Y
Nakao
Shunsuke
S
Kobayashi
Tamaki
T
Momoyama
Yu
Y
Higashiyama
Tetsuya
T
Minoda
Ayumi
A
Sano
Masako
M
Nomoto
Hisayo
H
Oishi
Kazuko
K
Hayashi
Hiroko
H
Ohta
Fumiko
F
Nishizaka
Satoko
S
Haga
Shinobu
S
Miura
Sachiko
S
Morishita
Tomomi
T
Kabeya
Yukihiro
Y
Terasawa
Kimihiro
K
Suzuki
Yutaka
Y
Ishii
Yasuyuki
Y
Asakawa
Shuichi
S
Takano
Hiroyoshi
H
Ohta
Niji
N
Kuroiwa
Haruko
H
Tanaka
Kan
K
Shimizu
Nobuyoshi
N
Sugano
Sumio
S
Sato
Naoki
N
Nozaki
Hisayoshi
H
Ogasawara
Naotake
N
Kohara
Yuji
Y
Kuroiwa
Tsuneyoshi
T
D000199:Actins / Q000235:genetics; D020418:Algal Proteins / Q000145:classification / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics; D002875:Chromosomes / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D019143:Evolution, Molecular; D016678:Genome; D023281:Genomics; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D018087:Plastids / Q000235:genetics / Q000502:physiology; D000461:Rhodophyta / Q000166:cytology / Q000235:genetics*; D017422:Sequence Analysis, DNA
D000199:Actins; D020418:Algal Proteins; D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal