GPCRs are integral membrane proteins that possess seven membrane-spanning domains or transmembrane helices. The extracellular parts of the receptor can be glycosylated. These extracellular loops also contain two highly conserved cysteine residues that form disulfide bonds to stabilize the receptor structure. Some seven-transmembrane helix proteins (channelrhodopsin) that resemble GPCRs may contain ion channels, within their protein.
gpCrs Are inTegrAL MembraNE ProteinS thAt poSSeSs seven mEMbRane-SpanniNg domains Or transmembranE hELices. thE exTracellulaR PArts Of ThE recEptoR CaN be GLYcosyLaTed. These eXTraCellUlar LOOps aLso conTAiN TWo highly conseRveD CyStEine rEsidueS that form DIsuLfide bondS tO sTAbiLize the recepTor strUCTure. somE seven-tRaNSmeMBrANe heLix pROteins (channeLrhoDopSIN) That resEMblE gpcrs mAy cOntaIN ion chaNNeLs, Within their proteiN.