D. Zoccola, P. Ganot, A. Bertucci, N.O. Caminiti-Segonds, N. Techer, C.R. Voolstra, M. Aranda, E. Tambutté, D. Allemand, J.R. Casey, S. Tambutté
Sci. Rep., 5, 9983, (2015)
The bicarbonate ion (HCO3−) is involved in two
major physiological processes in corals, biomineralization and
photosynthesis, yet no molecular data on bicarbonate transporters are
available. Here, we characterized plasma membrane-type HCO3− transporters in the scleractinian coral Stylophora pistillata.
Eight solute carrier (SLC) genes were found in the genome: five
homologs of mammalian-type SLC4 family members, and three of
mammalian-type SLC26 family members. Using relative expression analysis
and immunostaining, we analyzed the cellular distribution of these
transporters and conducted phylogenetic analyses to determine the extent
of conservation among cnidarian model organisms. Our data suggest that
the SLC4γ isoform is specific to scleractinian corals and responsible
for supplying HCO3− to the site of calcification.
Taken together, SLC4γ appears to be one of the key genes for skeleton
building in corals, which bears profound implications for our
understanding of coral biomineralization and the evolution of
scleractinian corals within cnidarians.