Lysophosphatidic acid LPA₁ receptor close-up

Lysophosphatidic acid is a local hormone / autacoid / growth factor, which induces a plethora of actions in the majority of cells in our organism. These actions include, among many others, the following: cell migration, proliferation and surviving, induction of gene transcription, platelet aggregation, smooth muscle contraction, myelinization, neurotransmitter release, cytoskeletal reorganization during the stress fiber formation, establishment of focal adhesions, neurite retraction, and cell rounding. The actions of lysophosphatidic acid are mediated through a family of G protein coupled receptors that includes five receptor subtypes, i.e. LPA_1,–5 receptors. These receptors couple to different G proteins, mainly Gi, Gq and G12/13 and their signaling pathways, besides there is evidence that they can transactivate EGF receptors to mediate some of their actions. The LPA₁ receptor was the first subtype to be cloned for this lysophospholipid. It plays an important role in development, is expressed in many cells and tissues and has been the most extensively studied. The present review presents current knowledge on the structure, function and regulation of this receptor subtype, its possible involvement in pathological conditions and suggests certain areas in which current knowledge is insufficient and further research is required.