Na+/K+-ATPase α-subunit ( nkaα) isoforms and their mRNA expression levels, overall nkaαα protein abundance, and kinetic properties of Nka in the skeletal muscle and three electric organs of the electric eel, electrophorus electricus

10.1371/journal.pone.0118352PLoS ONE103e011835

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

Ph.DDOCTOR OF PHILOSOPHY (FOS

Roles of zonula occludens proteins in T cell development and T cell activation.

Zonula Occludens Proteins (ZOPs) were found in cells of immune system recently. Due to the upregulation of ZO-2 during T cell activation by anti CD3/CD28 in vitro stimulation of T cells, we expressed a deep interest in exploring the roles of ZOPs in immunology. CD4-cre mice were sacrificed for the analysis of individual thymus and spleen. The cells were stained with CD4-APC and CD8-PE antibodies. We then analysed them with FACS Calibur to observe the T cell development and splenic T cells distribution. T cell proliferation was being observed by sacrificing OT-II CD4-cre for their lymph nodes and spleen and CD11c-cre mice for their bone marrow. After the co-culturing of different combinations of T cells and dendritic cells, [3H] thymidine was added and measured with a scintillation counter. Here, we showed that T cell development and splenic T cells distribution were not affected. We observed a higher proliferative ability in OT-II/CD4/ZO-1-/- and yet a lower proliferative ability in OT-II/CD4/ZO-2-/-. In conclusion, there may be other functions and mechanisms of ZOPs that have yet to be discovered. We hope that the uncovering of ZOPs’ new functions in the future will benefit the immunology field, hence solving the many human diseases that are mainly caused by tight junctions. IIIBachelor of Science in Biological Science

Light induces changes in activities of Na+/K+(NH4+)-ATPase, H+/K+(NH4+)-ATPase and glutamine synthetase in tissues involved directly or indirectly in light-enhanced calcification in the giant clam Tridacna squamosa

The objective of this study was to determine the effects of 12 h of exposure to light, as compared with 12 h of exposure to darkness (control), on enzymatic activities of transporters involved in the transport of NH4+ or H+, and activities of enzymes involved in converting NH4+ to glutamate/glutamine in inner mantle, outer mantle and ctenidia of the giant clam, Tridacna squamosa. Exposure to light resulted in a significant increase in the effectiveness of NH4+ in substitution for K+ to activate Na+/K+-ATPase (NKA), manifested as a significant increase in the Na+/NH4+-activated-NKA activity in the inner mantle. However, similar phenomena were not observed in the extensible outer mantle, which contained abundant symbiotic zooxanthellae. Hence, during light-enhanced calcification, H+ released from CaCO3 deposition could react with NH3 to form NH4+ in the extrapallial fluid, and NH4+ could probably be transported into the shell-facing inner mantle epithelium through NKA. Light also induced an increase in the activity of glutamine synthetase, which converts NH4+ and glutamate to glutamine, in the inner mantle. Taken together, these results explained observations reported elsewhere that light induced a significant increase in pH and a significant decrease in ammonia concentration in the extrapallial fluid, as well as a significant increase in the glutamine concentration in the inner mantle, of T. squamosa. Exposure of T. squamosa to light also led to a significant decrease in the N-ethylmaleimide (NEM)-sensitive-V-H+-ATPase (VATPase) in the inner mantle, and significant increases in the Na+/K+-activated-NKA, H+/NH4+-activated-H+/K+-ATPase and NEM-sensitive-VATPase activities in ctenidia, indicating that light-enhanced calcification might perturb Na+ homeostasis and acid/base balance in the hemolymph, and might involve the active uptake of NH4+ from the environment. This is the first report on light having direct enhancing effects on activities of certain transporters/en