Patent ID: 8389480

Claim:
A polypeptide comprising: a) a first domain comprising an intracellular loop, or a fragment thereof, of a G protein coupled receptor (GPCR), wherein said GPCR is a Class A or Class B GPCR, and wherein said fragment comprises at least 3 contiguous amino acid residues of the intracellular loop, and b) a second domain, attached to the first domain, wherein said second domain comprises a cell-penetrating, membrane-tethering hydrophobic moiety comprising: a tridecanoyl (C 13 ), myristoyl (C 14 ), pentadecanoyl (C 15 ), palmitoyl (C 16 ), phytanoyl (methyl substituted C 16 ), heptadecanoyl (C 17 ), stearoyl (C 18 ), nonadecanoyl (C 19 ), arachidoyl (C 20 ), heniecosanoyl (C 21 ), behenoyl (C 22 ), trucisanoyl (C 23 ), a lignoceroyl (C 24 ), a cholesterol, a phospholipid, a steroid, a sphingosine, a ceramide, an octyl-glycine, a 2-cyclohexylalanine, or a benzolylphenylalanine, wherein said polypeptide does not comprise an extracellular portion of the GPCR; and wherein said polypeptide is an agonist or antagonist of said GPCR.