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bioRxiv · 10.1101/188243

Anoctamin 9/TMEM16J is a Cation Channel Activated by cAMP/PKA Signal

Kim, H.·Lee, J.·Lee, B.·Jung, J.·Lee, M.-O.·Oh, U.
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Abstract

Anoctamins are membrane proteins that consist of 10 homologs. ANO1 and ANO2 are anion channels activated by intracellular calcium that meditate numerous physiological functions. ANO6 is a scramblase that redistributes phospholipids across the cell membrane. However, the others are not well characterized. We found ANO9/TMEM16J is a cation channel activated by a cAMP-dependent PKA. Intracellular cAMP activated robust currents in whole-cells expressing ANO9 and inhibited by PKA blockers. A cholera toxin and purified PKA also activated ANO9. The cAMP-induced ANO9 currents were permeable to cations. The mutation of a possible phosphorylation site at Ser245 elicited a block of the cAMP-dependent activation. High levels of Ano9 transcripts were found in intestines. Human intestinal SW480 cells showed cAMP-dependent currents. We conclude that ANO9 is a cation channel activated by the cAMP/PKA pathway and could play a role in intestine function.

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Kim, H., Lee, J., Lee, B., Jung, J., Lee, M.-O., Oh, U.. 2017-09-13. Anoctamin 9/TMEM16J is a Cation Channel Activated by cAMP/PKA Signal. https://doi.org/10.1101/188243

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