Dataset Information

Symbiosis-dependent gene expression in coral-dinoflagellate association: cloning and characterization of a P-type H+-ATPase gene.

ABSTRACT: We report the molecular cloning of a H(+)-ATPase in the symbiotic dinoflagellate, Symbiodinium sp. previously suggested by pharmacological studies to be involved in carbon-concentrating mechanism used by zooxanthellae when they are in symbiosis with corals. This gene encodes a protein of 975 amino acids with a calculated mass of about 105 kDa. The structure of the protein shows a typical P-type H(+)-ATPase structure (type IIIa plasma membrane H(+)-ATPases) and phylogenetic analyses show that this new proton pump groups with diatoms in the Chromoalveolates group. This Symbiodinium H(+)-ATPase is specifically expressed when zooxanthellae are engaged in a symbiotic relationship with the coral partner but not in free-living dinoflagellates. This proton pump, therefore, could be involved in the acidification of the perisymbiotic space leading to bicarbonate dehydration by carbonic anhydrase activity in order to supply inorganic carbon for photosynthesis as suggested by earlier studies. To our knowledge, this work provides the first example of a symbiosis-dependent gene in zooxanthellae and confirms the importance of H(+)-ATPase in coral-dinoflagellate symbiosis.

SUBMITTER: Bertucci A

PROVIDER: S-EPMC2842621 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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Symbiosis-dependent gene expression in coral-dinoflagellate association: cloning and characterization of a P-type H+-ATPase gene.

Bertucci Anthony A Tambutté Eric E Tambutté Sylvie S Allemand Denis D Zoccola Didier D

Proceedings. Biological sciences 20090930 1678

We report the molecular cloning of a H(+)-ATPase in the symbiotic dinoflagellate, Symbiodinium sp. previously suggested by pharmacological studies to be involved in carbon-concentrating mechanism used by zooxanthellae when they are in symbiosis with corals. This gene encodes a protein of 975 amino acids with a calculated mass of about 105 kDa. The structure of the protein shows a typical P-type H(+)-ATPase structure (type IIIa plasma membrane H(+)-ATPases) and phylogenetic analyses show that thi ...[more]

PMID: 19793745

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Project description:Symbiodinium are responsible for the majority of primary production in coral reefs and found in a mutualistic symbiosis with multiple animal phyla. However, little is known about the molecular signals involved in the establishment of this symbiosis and whether it initiates during host larval development. To address this question, we monitored the expression of a putative symbiosis-specific gene (H+-ATPase) in Symbiodinium A1 ex hospite and in association with larvae of a scleractinian coral (Mussismilia hispida), a nudibranch (Berghia stephanieae) and a giant clam (Tridacna crocea). We acquired broodstock for each host, induced spawning and cultured the larvae. Symbiodinium cells were offered and larval samples taken for each host during the first 72 h after symbiont addition. In addition, control samples including free-living Symbiodinium and broodstock tissue containing symbionts for each host were collected. RNA extraction and RT-PCR were performed and amplified products cloned and sequenced. Our results show that H+-ATPase was expressed in Symbiodinium associated with coral and giant clam larvae, but not with nudibranch larvae, which digested the symbionts. Broodstock tissue for coral and giant clam also expressed H+-ATPase, but not the nudibranch tissue sample. Our results of the expression of H+-ATPase as a marker gene suggest that symbiosis between Symbiodinium and M. hispida and T. crocea is established during host larval development. Conversely, in the case of B. stephanieae larvae, evidence does not support a mutualistic relationship. Our study supports the utilization of H+-ATPase expression as a marker for assessing Symbiodinium-invertebrate relationships with applications for the differentiation of symbiotic and non-symbiotic associations. At the same time, insights from a single marker gene approach are limited and future studies should direct the identification of additional symbiosis-specific genes, ideally from both symbiont and host.

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Dataset Information

Symbiosis-dependent gene expression in coral-dinoflagellate association: cloning and characterization of a P-type H+-ATPase gene.

Publications

Symbiosis-dependent gene expression in coral-dinoflagellate association: cloning and characterization of a P-type H+-ATPase gene.

Similar Datasets

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