Responses of the marine diatom Thalassiosira pseudonana to changes in CO2concentration: a proteomic approach.
The concentration of CO2in many aquatic systems is variable, often lower than the KMof the primary carboxylating enzyme Rubisco, and in order to photosynthesize efficiently, many algae operate a facultative CO2concentrating mechanism (CCM). Here we measured the responses of a marine diatom, Thalassiosira pseudonana, to high and low concentrations of CO2at the level of transcripts, proteins and enzyme activity. Low CO2caused many metabolic pathways to be remodeled. Carbon acquisition enzymes, primarily carbonic anhydrase, stress, degradation and signaling proteins were more abundant while proteins associated with nitrogen metabolism, energy production and chaperones were less abundant. A protein with similarities to the Ca2+/ calmodulin dependent protein kinase II_association domain, having a chloroplast targeting sequence, was only present at low CO2. This protein might be a specific response to CO2limitation since a previous study showed that other stresses caused its reduction. The protein sequence was found in other marine diatoms and may play an important role in their response to low CO2concentration.
Aix Marseille Univ, CNRS, BIP, IMM, 31 Chemin J. Aiguier, B.P. 71, 13 402 Marseille, Cedex 20, France.
Romain
R
Clement
Plate-forme Protéomique, Marseille Protéomique (MaP) IBiSA labelled, Institut de Microbiologie de la Méditerranée, FR 3479, CNRS, 31 Chemin Joseph Aiguier, B.P. 71, 13402 Marseille Cedex 20, France.
Sabrina
S
Lignon
Plate-forme Protéomique, Marseille Protéomique (MaP) IBiSA labelled, Institut de Microbiologie de la Méditerranée, FR 3479, CNRS, 31 Chemin Joseph Aiguier, B.P. 71, 13402 Marseille Cedex 20, France.
Pascal
P
Mansuelle
Aix Marseille Univ, CNRS, BIP, IMM, 31 Chemin J. Aiguier, B.P. 71, 13 402 Marseille, Cedex 20, France.
Erik
E
Jensen
Aix Marseille Univ, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille Protéomique, Marseille, France.
Matthieu
M
Pophillat
Plate-forme Protéomique, Marseille Protéomique (MaP) IBiSA labelled, Institut de Microbiologie de la Méditerranée, FR 3479, CNRS, 31 Chemin Joseph Aiguier, B.P. 71, 13402 Marseille Cedex 20, France.
Regine
R
Lebrun
Plate-forme Transcriptomique, Institut de Microbiologie de la Méditerranée, FR 3479, CNRS, 31 Chemin Joseph Aiguier, B.P. 71, 13402 Marseille Cedex 20, France.
Yann
Y
Denis
Aix Marseille Univ, CNRS, BIP, IMM, 31 Chemin J. Aiguier, B.P. 71, 13 402 Marseille, Cedex 20, France.
Carine
C
Puppo
Lake Ecosystems Group, Centre for Ecology &Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP UK.
Stephen C
SC
Maberly
Aix Marseille Univ, CNRS, BIP, IMM, 31 Chemin J. Aiguier, B.P. 71, 13 402 Marseille, Cedex 20, France.
Brigitte
B
Gontero
D000595:Amino Acid Sequence; D059001:Aquatic Organisms / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D002245:Carbon Dioxide / Q000494:pharmacology*; D017377:Diatoms / Q000166:cytology / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005786:Gene Expression Regulation / Q000187:drug effects; D016678:Genome; D008954:Models, Biological; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012995:Solubility
D011506:Proteins; D012333:RNA, Messenger; D002245:Carbon Dioxide