MOLECULAR BIOLOGY AND PHYSIOLOGICAL FUNCTIONS OF ELECTROGENIC Na+- HCO3− COTRANSPORTERS IN THREE ORGANS OF THE FLUTED GIANT CLAM, TRIDACNA SQUAMOSA

Abstract

Giant clams harbor photosynthetic dinoflagellates as symbionts and can conduct light-enhanced shell formation (calcification). As the photosynthesizing symbionts and light-enhanced shell formation require the increase in the supply of inorganic carbon (Ci), the host clam must increase the uptake of Ci from the external seawater during illumination. The purpose of this thesis is to study the molecular biology and physiological function of electrogenic Na+-HCO3− cotransporters in three organs (ctenidium, inner mantle, and outer mantle) of the fluted giant clam Tridacna squamosa. We aim to clone and obtain the full coding sequences of homologs of NBCes (NBCes-like), elucidate the cellular and subcellular localization of NBCes-like using immunofluorescence microscopy, and determine the effects of illumination on transcript levels and protein abundance of NBCes-like/NBCes-like from the three organs. Results from this study may offer insights into ways to enhance the growth and survivorship of giant clams confronted with global change effects.