Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors
A member of THIK (two pore domain halothane-inhibited K+) channels, THIK-1, was reported as a target of Gi/o-coupled receptors (Gi/o-Rs) in neurons and microglia. We confirmed that in HEK293T cells the THIK-1 channel is activated by Gi/o-Rs and found that Gq-coupled receptors (Gq-Rs) also activates...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2023-01-01
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| Series: | PLoS ONE |
| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10132538/?tool=EBI |
| _version_ | 1797836794360758272 |
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| author | Michihiro Tateyama Yoshihiro Kubo |
| author_facet | Michihiro Tateyama Yoshihiro Kubo |
| author_sort | Michihiro Tateyama |
| collection | DOAJ |
| description | A member of THIK (two pore domain halothane-inhibited K+) channels, THIK-1, was reported as a target of Gi/o-coupled receptors (Gi/o-Rs) in neurons and microglia. We confirmed that in HEK293T cells the THIK-1 channel is activated by Gi/o-Rs and found that Gq-coupled receptors (Gq-Rs) also activates the channel. The effects of Gi/o-Rs and Gq-Rs were inhibited by the Gi/o inhibitor pertussis toxin and phospholipase C (PLC) inhibitor, respectively. The effects of Gi/o-Rs were attenuated when consensus Gβγ binding motif at the C-tail of the THIK-1 channel was mutated, suggesting that Gβγ serves as a THIK-1 channel activator upon the stimulation of Gi/o-Rs. As to the effects of Gq-Rs on the THIK-1 channel, a protein kinase C inhibitor and calcium chelators failed to inhibit the effect of a Gq coupled muscarinic M1R. Neither the hydrolysis of phosphatidyl inositol bisphosphate induced by voltage sensitive phosphatase nor the application of a diacylglycerol analogue, OAG, increased the channel current. The mediator of Gq-dependent activation of the THIK-1 channel remained unsolved. The effects of Gi/o- and Gq-Rs on the THIK-2 channel were also investigated, by using a THIK-2 mutant channel whose N-terminal domain is deleted to improve the surface membrane expression. We observed that Gi/o- and Gq-Rs activate the mutated THIK-2 channel, similarly to the THIK-1 channel. Interestingly, heterodimeric channels of THIK-1 and THIK-2 responded to Gi/o-R and Gq-R stimulation. Taken together, Gi/o- or Gq-Rs activates the THIK-1 and THIK-2 channels in a Gβγ or PLC dependent manner, respectively. |
| first_indexed | 2024-04-09T15:14:40Z |
| format | Article |
| id | doaj.art-0da34f0e903e4d6888c85bf183341562 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-09T15:14:40Z |
| publishDate | 2023-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-0da34f0e903e4d6888c85bf1833415622023-04-30T05:31:23ZengPublic Library of Science (PLoS)PLoS ONE1932-62032023-01-01184Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptorsMichihiro TateyamaYoshihiro KuboA member of THIK (two pore domain halothane-inhibited K+) channels, THIK-1, was reported as a target of Gi/o-coupled receptors (Gi/o-Rs) in neurons and microglia. We confirmed that in HEK293T cells the THIK-1 channel is activated by Gi/o-Rs and found that Gq-coupled receptors (Gq-Rs) also activates the channel. The effects of Gi/o-Rs and Gq-Rs were inhibited by the Gi/o inhibitor pertussis toxin and phospholipase C (PLC) inhibitor, respectively. The effects of Gi/o-Rs were attenuated when consensus Gβγ binding motif at the C-tail of the THIK-1 channel was mutated, suggesting that Gβγ serves as a THIK-1 channel activator upon the stimulation of Gi/o-Rs. As to the effects of Gq-Rs on the THIK-1 channel, a protein kinase C inhibitor and calcium chelators failed to inhibit the effect of a Gq coupled muscarinic M1R. Neither the hydrolysis of phosphatidyl inositol bisphosphate induced by voltage sensitive phosphatase nor the application of a diacylglycerol analogue, OAG, increased the channel current. The mediator of Gq-dependent activation of the THIK-1 channel remained unsolved. The effects of Gi/o- and Gq-Rs on the THIK-2 channel were also investigated, by using a THIK-2 mutant channel whose N-terminal domain is deleted to improve the surface membrane expression. We observed that Gi/o- and Gq-Rs activate the mutated THIK-2 channel, similarly to the THIK-1 channel. Interestingly, heterodimeric channels of THIK-1 and THIK-2 responded to Gi/o-R and Gq-R stimulation. Taken together, Gi/o- or Gq-Rs activates the THIK-1 and THIK-2 channels in a Gβγ or PLC dependent manner, respectively.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10132538/?tool=EBI |
| spellingShingle | Michihiro Tateyama Yoshihiro Kubo Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors PLoS ONE |
| title | Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors |
| title_full | Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors |
| title_fullStr | Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors |
| title_full_unstemmed | Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors |
| title_short | Regulation of the two-pore domain potassium channel, THIK-1 and THIK-2, by G protein coupled receptors |
| title_sort | regulation of the two pore domain potassium channel thik 1 and thik 2 by g protein coupled receptors |
| url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10132538/?tool=EBI |
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