Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling
<p>Abstract</p> <p>Background</p> <p>A cholesterol-palmitoyl interaction has been reported to occur in the dimeric interface of the β<sub>2</sub>-adrenergic receptor crystal structure. We sought to investigate whether a similar phenomenon could be observed w...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2012-03-01
|
| Series: | BMC Cell Biology |
| Subjects: | |
| Online Access: | http://www.biomedcentral.com/1471-2121/13/6 |
| _version_ | 1818236447431327744 |
|---|---|
| author | Zheng Hui Pearsall Elizabeth A Hurst Dow P Zhang Yuhan Chu Ji Zhou Yali Reggio Patricia H Loh Horace H Law Ping-Yee |
| author_facet | Zheng Hui Pearsall Elizabeth A Hurst Dow P Zhang Yuhan Chu Ji Zhou Yali Reggio Patricia H Loh Horace H Law Ping-Yee |
| author_sort | Zheng Hui |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>A cholesterol-palmitoyl interaction has been reported to occur in the dimeric interface of the β<sub>2</sub>-adrenergic receptor crystal structure. We sought to investigate whether a similar phenomenon could be observed with μ-opioid receptor (OPRM1), and if so, to assess the role of cholesterol in this class of G protein-coupled receptor (GPCR) signaling.</p> <p>Results</p> <p>C3.55(170) was determined to be the palmitoylation site of OPRM1. Mutation of this Cys to Ala did not affect the binding of agonists, but attenuated receptor signaling and decreased cholesterol associated with the receptor signaling complex. In addition, both attenuation of receptor palmitoylation (by mutation of C3.55[170] to Ala) and inhibition of cholesterol synthesis (by treating the cells with simvastatin, a HMG-CoA reductase inhibitor) impaired receptor signaling, possibly by decreasing receptor homodimerization and Gαi2 coupling; this was demonstrated by co-immunoprecipitation, immunofluorescence colocalization and fluorescence resonance energy transfer (FRET) analyses. A computational model of the OPRM1 homodimer structure indicated that a specific cholesterol-palmitoyl interaction can facilitate OPRM1 homodimerization at the TMH4-TMH4 interface.</p> <p>Conclusions</p> <p>We demonstrate that C3.55(170) is the palmitoylation site of OPRM1 and identify a cholesterol-palmitoyl interaction in the OPRM1 complex. Our findings suggest that this interaction contributes to OPRM1 signaling by facilitating receptor homodimerization and G protein coupling. This conclusion is supported by computational modeling of the OPRM1 homodimer.</p> |
| first_indexed | 2024-12-12T12:10:01Z |
| format | Article |
| id | doaj.art-74be7eb98e0c4431abc22b192f3f2c42 |
| institution | Directory Open Access Journal |
| issn | 1471-2121 |
| language | English |
| last_indexed | 2024-12-12T12:10:01Z |
| publishDate | 2012-03-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Cell Biology |
| spelling | doaj.art-74be7eb98e0c4431abc22b192f3f2c422022-12-22T00:24:55ZengBMCBMC Cell Biology1471-21212012-03-01131610.1186/1471-2121-13-6Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein couplingZheng HuiPearsall Elizabeth AHurst Dow PZhang YuhanChu JiZhou YaliReggio Patricia HLoh Horace HLaw Ping-Yee<p>Abstract</p> <p>Background</p> <p>A cholesterol-palmitoyl interaction has been reported to occur in the dimeric interface of the β<sub>2</sub>-adrenergic receptor crystal structure. We sought to investigate whether a similar phenomenon could be observed with μ-opioid receptor (OPRM1), and if so, to assess the role of cholesterol in this class of G protein-coupled receptor (GPCR) signaling.</p> <p>Results</p> <p>C3.55(170) was determined to be the palmitoylation site of OPRM1. Mutation of this Cys to Ala did not affect the binding of agonists, but attenuated receptor signaling and decreased cholesterol associated with the receptor signaling complex. In addition, both attenuation of receptor palmitoylation (by mutation of C3.55[170] to Ala) and inhibition of cholesterol synthesis (by treating the cells with simvastatin, a HMG-CoA reductase inhibitor) impaired receptor signaling, possibly by decreasing receptor homodimerization and Gαi2 coupling; this was demonstrated by co-immunoprecipitation, immunofluorescence colocalization and fluorescence resonance energy transfer (FRET) analyses. A computational model of the OPRM1 homodimer structure indicated that a specific cholesterol-palmitoyl interaction can facilitate OPRM1 homodimerization at the TMH4-TMH4 interface.</p> <p>Conclusions</p> <p>We demonstrate that C3.55(170) is the palmitoylation site of OPRM1 and identify a cholesterol-palmitoyl interaction in the OPRM1 complex. Our findings suggest that this interaction contributes to OPRM1 signaling by facilitating receptor homodimerization and G protein coupling. This conclusion is supported by computational modeling of the OPRM1 homodimer.</p>http://www.biomedcentral.com/1471-2121/13/6PalmitoylationCholesterolHomodimerizationG protein coupling |
| spellingShingle | Zheng Hui Pearsall Elizabeth A Hurst Dow P Zhang Yuhan Chu Ji Zhou Yali Reggio Patricia H Loh Horace H Law Ping-Yee Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling BMC Cell Biology Palmitoylation Cholesterol Homodimerization G protein coupling |
| title | Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling |
| title_full | Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling |
| title_fullStr | Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling |
| title_full_unstemmed | Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling |
| title_short | Palmitoylation and membrane cholesterol stabilize μ-opioid receptor homodimerization and G protein coupling |
| title_sort | palmitoylation and membrane cholesterol stabilize μ opioid receptor homodimerization and g protein coupling |
| topic | Palmitoylation Cholesterol Homodimerization G protein coupling |
| url | http://www.biomedcentral.com/1471-2121/13/6 |
| work_keys_str_mv | AT zhenghui palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT pearsallelizabetha palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT hurstdowp palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT zhangyuhan palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT chuji palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT zhouyali palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT reggiopatriciah palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT lohhoraceh palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling AT lawpingyee palmitoylationandmembranecholesterolstabilizemopioidreceptorhomodimerizationandgproteincoupling |