Molecular mechanism of TMEM16A regulation: role of CaMKII and PP1/PP2A

Autor: Matthew B. Hawn, Normand Leblanc, Michael Wiwchar, Fiona Cunningham, Ramon Jose Ayon, Iain A. Greenwood, Maria L. Valencik, Abigail S. Forrest, Joydeep Aoun, Cherie A. Singer
Rok vydání: 2019
Předmět:
0301 basic medicine
Benzylamines
Patch-Clamp Techniques
Physiology
Phosphatase
030204 cardiovascular system & hematology
environment and public health
Mice
03 medical and health sciences
Adenosine Triphosphate
0302 clinical medicine
Chlorides
Protein Phosphatase 1
Ca2+/calmodulin-dependent protein kinase
Okadaic Acid
Animals
Humans
Amino Acid Sequence
Protein Phosphatase 2
Phosphorylation
Evoked Potentials
Gene
Anoctamin-1
Sulfonamides
Ion Transport
Sequence Homology
Amino Acid
Mechanism (biology)
Chemistry
Cell Biology
Protein phosphatase 2
Protein kinase II
Neoplasm Proteins
Cell biology
enzymes and coenzymes (carbohydrates)
HEK293 Cells
030104 developmental biology
Gene Expression Regulation
Cantharidin
Molecular mechanism
Calcium
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Peptides
Sequence Alignment
Research Article
Signal Transduction
Zdroj: Am J Physiol Cell Physiol
ISSN: 1522-1563
0363-6143
DOI: 10.1152/ajpcell.00059.2018
Popis: This study explored the mechanism by which Ca2+-activated Cl−channels (CaCCs) encoded by the Tmem16a gene are regulated by calmodulin-dependent protein kinase II (CaMKII) and protein phosphatases 1 (PP1) and 2A (PP2A). Ca2+-activated Cl−currents ( IClCa) were recorded from HEK-293 cells expressing mouse TMEM16A. IClCawere evoked using a pipette solution in which free Ca2+concentration was clamped to 500 nM, in the presence (5 mM) or absence of ATP. With 5 mM ATP, IClCadecayed to ClCarundown seen with ATP-containing pipette solution was greatly diminished by omitting ATP. IClCarecorded after 20 min of cell dialysis with 0 ATP were more than twofold larger than those recorded with 5 mM ATP. Intracellular application of autocamtide-2-related inhibitory peptide (5 µM) or KN-93 (10 µM), two specific CaMKII inhibitors, produced a similar attenuation of TMEM16A rundown. In contrast, internal application of okadaic acid (30 nM) or cantharidin (100 nM), two nonselective PP1 and PP2A blockers, promoted the rundown of TMEM16A in cells dialyzed with 0 ATP. Mutating serine 528 of TMEM16A to an alanine led to a similar inhibition of TMEM16A rundown to that exerted by either one of the two CaMKII inhibitors tested, which was not observed for three putative CaMKII consensus sites for phosphorylation (T273, T622, and S730). Our results suggest that TMEM16A-mediated CaCCs are regulated by CaMKII and PP1/PP2A. Our data also suggest that serine 528 of TMEM16A is an important contributor to the regulation of IClCaby CaMKII.
Databáze: OpenAIRE
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