Journal article
Down-modulation of the G-protein-coupled Estrogen Receptor, GPER, from the Cell Surface Occurs via a trans-Golgi-Proteasome Pathway
The Journal of biological chemistry, Vol.286(25), pp.22441-22455
06/24/2011
DOI: 10.1074/jbc.M111.224071
PMCID: PMC3121390
PMID: 21540189
Abstract
GPER is a G
s
-coupled seven-transmembrane receptor that has been linked to specific estrogen binding and signaling activities that are manifested by plasma membrane-associated enzymes. However, in many cell types, GPER is predominately localized to the endoplasmic reticulum (ER), and only minor amounts of receptor are detectable at the cell surface, an observation that has caused controversy regarding its role as a plasma membrane estrogen receptor. Here, we show that GPER constitutively buds intracellularly into EEA-1+ endosomes from clathrin-coated pits. Nonvisual arrestins-2/-3 do not co-localize with GPER, and expression of arrestin-2 dominant-negative mutants lacking clathrin- or β-adaptin interaction sites fails to block GPER internalization suggesting that arrestins are not involved in GPER endocytosis. Like β1AR, which recycles to the plasma membrane, GPER co-traffics with transferrin+, Rab11+ recycling endosomes. However, endocytosed GPER does not recycle to the cell surface, but instead returns to the
trans
-Golgi network (TGN) and does not re-enter the ER. GPER is ubiquitinated at the cell surface, exhibits a short half-life (
t
½
<1 h), and is protected from degradation by the proteasome inhibitor, MG132. Disruption of the TGN by brefeldin A induces the accumulation of endocytosed GPER in Rab11+ perinuclear endosomes and prevents GPER degradation. Our results provide an explanation as to why GPER is not readily detected on the cell surface in some cell types and further suggest that TGN serves as the checkpoint for degradation of endocytosed GPER.
Details
- Title: Subtitle
- Down-modulation of the G-protein-coupled Estrogen Receptor, GPER, from the Cell Surface Occurs via a trans-Golgi-Proteasome Pathway
- Creators
- Shi-Bin Cheng - From the Division of Hematology & Oncology, Rhode Island Hospital and Brown University, Providence, Rhode Island 02903Jeffrey A Quinn - From the Division of Hematology & Oncology, Rhode Island Hospital and Brown University, Providence, Rhode Island 02903Carl T Graeber - From the Division of Hematology & Oncology, Rhode Island Hospital and Brown University, Providence, Rhode Island 02903Edward J Filardo - From the Division of Hematology & Oncology, Rhode Island Hospital and Brown University, Providence, Rhode Island 02903
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.286(25), pp.22441-22455
- DOI
- 10.1074/jbc.M111.224071
- PMID
- 21540189
- PMCID
- PMC3121390
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Publisher
- American Society for Biochemistry and Molecular Biology; 9650 Rockville Pike, Bethesda, MD 20814, U.S.A
- Grant note
- R01 CA119165-01A2 / National Institutes of Health
- Alternative title
- GPER Down-regulation via a TGN-proteasomal Pathway
- Language
- English
- Date published
- 06/24/2011
- Academic Unit
- Pharmaceutical Sciences and Experimental Therapeutics; Surgery; Internal Medicine
- Record Identifier
- 9984051590902771
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