Expression profiling-based identification of CO2-responsive genes regulated by CCM1 controlling a carbon-concentrating mechanism in Chlamydomonas reinhardtii.
Photosynthetic acclimation to CO2-limiting stress is associated with control of genetic and physiological responses through a signal transduction pathway, followed by integrated monitoring of the environmental changes. Although several CO2-responsive genes have been previously isolated, genome-wide analysis has not been applied to the isolation of CO2-responsive genes that may function as part of a carbon-concentrating mechanism (CCM) in photosynthetic eukaryotes. By comparing expression profiles of cells grown under CO2-rich conditions with those of cells grown under CO2-limiting conditions using a cDNA membrane array containing 10,368 expressed sequence tags, 51 low-CO2 inducible genes and 32 genes repressed by low CO2 whose mRNA levels were changed more than 2.5-fold in Chlamydomonas reinhardtii Dangeard were detected. The fact that the induction of almost all low-CO2 inducible genes was impaired in the ccm1 mutant suggests that CCM1 is a master regulator of CCM through putative low-CO2 signal transduction pathways. Among low-CO2 inducible genes, two novel genes, LciA and LciB, were identified, which may be involved in inorganic carbon transport. Possible functions of low-CO2 inducible and/or CCM1-regulated genes are discussed in relation to the CCM.
Miura
Kenji
K
Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan.
Yamano
Takashi
T
Yoshioka
Satoshi
S
Kohinata
Tsutomu
T
Inoue
Yoshihiro
Y
Taniguchi
Fumiya
F
Asamizu
Erika
E
Nakamura
Yasukazu
Y
Tabata
Satoshi
S
Yamato
Katsuyuki T
KT
Ohyama
Kanji
K
Fukuzawa
Hideya
H
D000064:Acclimatization; D000595:Amino Acid Sequence; D000818:Animals; D002244:Carbon / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism / Q000494:pharmacology*; D016825:Chlamydomonas reinhardtii / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D017124:Conserved Sequence; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D015800:Protozoan Proteins; D002245:Carbon Dioxide; D002244:Carbon