The mammalian type I GNRH receptor (GNRHR) is unique among G protein-coupled receptors (GPCRs) because of the absence of an intracellular C-terminus. Previously, we have found that the murine GNRHR is constitutively localized to low-density membrane microdomains termed lipid rafts. As such, association of the GNRHR with lipid rafts may reflect both a loss (C-terminus) and a gain (raft association address) of structural characteristics. To address this, we fused either the full-length C-terminus from the nonraft-associated LH receptor (LHCGR; GNRHR-LF) or a truncated (t631) LHCGR C-terminus to the GNRHR. These chimeric receptors are trafficked to the plasma membrane, bind ligand, and display increased agonist-induced receptor internalization, but they do not partition into lipid rafts. Thus, a heterologous C-terminus from a nonraft-associated GPCR redirects localization of the GNRHR to nonraft domains. In contrast to the murine GNRHR, the catfish GNRHR (cfGNRHR) possesses an intracellular C-terminus. We found that the cfGNRHR was localized to lipid rafts and that the cfGNRHR C-terminus did not alter raft localization of the mammalian receptor. Consistent with placement in different lipid microenvironments within the plasma membrane, fluorescence recovery after photobleaching revealed different lateral diffusion phenotypes of the raft-associated GNRHR and cfGNRHR versus the nonraft-associated GNRHR-LF fusion protein. We conclude that whereas an intracellular C-terminus is capable of redirecting the GNRHR to nonraft compartments, this is not a generalized feature of GPCR C-terminal tails. Thus, constitutive raft localization of the GNRHR is not simply a result of the loss of an intracellular C-terminus.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.