Carbonic anhydrase in the scleractinian coral Stylophora pistillata: characterization, localization, and role in biomineralization.
Carbonic anhydrases (CA) play an important role in biomineralization from invertebrates to vertebrates. Previous experiments have investigated the role of CA in coral calcification, mainly by pharmacological approaches. This study reports the molecular cloning, sequencing, and immunolocalization of a CA isolated from the scleractinian coral Stylophora pistillata, named STPCA. Results show that STPCA is a secreted form of alpha-CA, which possesses a CA catalytic function, similar to the secreted human CAVI. We localized this enzyme at the calicoblastic ectoderm level, which is responsible for the precipitation of the skeleton. This localization supports the role of STPCA in the calcification process. In symbiotic scleractinian corals, calcification is stimulated by light, a phenomenon called "light-enhanced calcification" (LEC). The mechanism by which symbiont photosynthesis stimulates calcification is still enigmatic. We tested the hypothesis that coral genes are differentially expressed under light and dark conditions. By real-time PCR, we investigated the differential expression of STPCA to determine its role in the LEC phenomenon. Results show that the STPCA gene is expressed 2-fold more during the dark than the light. We suggest that in the dark, up-regulation of the STPCA gene represents a mechanism to cope with night acidosis.
Moya
Aurélie
A
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Tambutté
Sylvie
S
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Bertucci
Anthony
A
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Tambutté
Eric
E
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Lotto
Séverine
S
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Vullo
Daniela
D
Dipartimento di Chimica, University of Florence, Via della Lastruccia, 3, Rm. 188, Polo Scientifico, 50019-Sesto Fiorentino (Firenze), Italy.
Supuran
Claudiu T
CT
Dipartimento di Chimica, University of Florence, Via della Lastruccia, 3, Rm. 188, Polo Scientifico, 50019-Sesto Fiorentino (Firenze), Italy.
Allemand
Denis
D
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the.
Zoccola
Didier
D
Centre Scientifique de Monaco, Avenue Saint-Martin, MC-98000 Principality of Monaco and the. Electronic address: zoccola@centrescientifique.mc.
D000595:Amino Acid Sequence; D000818:Animals; D037421:Anthozoa; D002113:Calcification, Physiologic; D002256:Carbonic Anhydrases / Q000378:metabolism*; D002384:Catalysis; D002460:Cell Line; D005786:Gene Expression Regulation; D006801:Humans; D008027:Light; D008954:Models, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid
D011994:Recombinant Proteins; D002256:Carbonic Anhydrases