G protein-coupled receptors (GPCRs), such as GPR44, are integral membrane proteins containing 7 putative transmembrane domains (TMs). These proteins mediate signals to the interior of the cell via activation of heterotrimeric G proteins that in turn activate various effector proteins, ultimately resulting in a physiologic response.[supplied by OMIM]
GPR44 has recently been found to belong to the prostanoid receptor family and named DP2, with this becoming the official IUPHAR nomenclature.
GPR44 has recently been found when activated by elevated level of prostaglandin D2 (PGD2), it could inhibit hair growth. This suggests the PGD2-GPR44 pathway as a potential target for bald treatment. A particularly promising compound for blocking the PGD2-GPR44 pathway is a compound known as TM-30089, which exhibits a "functional insurmountability" of PGD2 expression.
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