Autotaxin in embryonic development

Autotaxin (ATX) is a secreted lysophospholipase D that generates the multifunctional lipid mediator lysophosphatidic acid (LPA). LPA signals through six distinct G protein-coupled receptors, acting alone or in concert to activate multiple effector pathways. The ATX-LPA signaling axis is implicated in a remarkably wide variety of physiological and pathological processes and plays a vital role in embryonic development. Disruption of the ATX-encoding gene (Enpp2) in mice results in intrauterine death due to vascular defects in the extra-embryonic yolk sac and embryo proper. In addition, Enpp2 (-/-) embryos show impaired neural development. The observed angiogenic defects are attributable, at least in part, to loss of LPA signaling through the Gα(12/13)-linked RhoA-ROCK-actin remodeling pathway. Studies in zebrafish also have uncovered a dual role for ATX in both vascular and neural development; furthermore, they point to a key role for ATX-LPA signaling in the regulation of left-right asymmetry. Here we discuss our present understanding of the role of ATX-LPA signaling in vertebrate development. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.