Anoctamin family 유전자들의 mouse 조직 분포

Abstract

Cell needs to push ion through interior and exterior of cell membrane for signal transduction, rapid change such as muscle contraction, epithelial transduction of nutrition, activation of T-cell and insulin secretion from pancreatic beta-cell. Cell membrane is a lipid bi-layer which is impermeable to most ions. Cell uses ion channels to regulate the flow of ions. Ion channels are pore-forming proteins that control the small voltage gradient across the plasma membrane of cells by allowing the flow of ions down their electrochemical gradient. Ion channels are classified by the nature of their gating, the species of ions passing through those gates, the number of gates and pores and localization of proteins. Chloride ion flows through one of these channels, which are called chloride channels. Chloride channels show a variety of important physiological and cellular roles that include regulation of pH, volume homeostasis, organic solute transport, cell migration, cell proliferation and differentiation. Chloride channel has five different types; cAMP-activated, calciumactivated, volume-activated, voltage-activated, and ligand-gated chloride channel. This paper focused on the calcium-activated chloride channel (CaCC).

Our laboratory found Anoctamin/TMEM16 family by using in-silico gene mining method in 2008(Yang, Cho et al. 2008). ANO1 and ANO2 have been known to be activated by intracellular Ca2+. ANO1 is involved in secretion systems in various tissues, and ANO2 is known as a calcium-activated chloride channel (CaCC) in the olfactory bulbs. But, molecular functions of other genes have not yet been found.

The aim of this paper is to systemically quantify the levels of Anoctamin mRNA in various types of tissues using sensitive and specific real time quantitative-polymerase chain reaction methodology.

As a result, ANO1, 6 and 10 were expressed in all types of tissues, whereas ANO2, 3, 4, and 8 showed high expression in the brain, ANO5 in the tongue and skeletal muscle, and ANO7 and 9 in the digestive organs such as the stomach, small intestine, and colon.

ANO8 mRNA has higher expression levels than other ANO genes in Brain and DRG. ANO8 protein was expressed in the plasma membrane. In the brain, ANO8 protein was detected in the axon and the dendrite. And the large and small DRG neurons had ANO8 protein.

These results can contribute to the study of unknown function of each ANO family genes.