Autotaxin: structure-function and signaling.

Area of Science:

• Biochemistry
• Cell Biology
• Enzymology

Background:

• Autotaxin (ATX) is a secreted enzyme acting as a lysophospholipase D (lysoPLD).
• ATX hydrolyzes lysophospholipids to produce lysophosphatidic acid (LPA).
• ATX-LPA signaling pathways are vital in development and implicated in numerous physiological and pathological processes, including cancer and immune responses.

Purpose of the Study:

• To elucidate the structure-function relationships of Autotaxin (ATX).
• To understand the signaling mechanisms of ATX and its interaction with target cells.
• To explore how ATX isoforms target LPA production and discuss the development of ATX inhibitors.

Main Methods:

• Structural and functional analyses of the ATX catalytic domain.
• Investigation of ATX binding to cell surface molecules like integrins and heparan sulfate proteoglycans.
• Review of current understanding of ATX signaling and inhibitor development.

Main Results:

• The ATX catalytic domain possesses a unique bimetallic active site, a shallow binding groove, and a deep lipid-binding pocket.
• An adjacent open tunnel in the catalytic domain suggests a currently unknown function.
• Distinct ATX isoforms utilize specific mechanisms to localize LPA production at the plasma membrane through interactions with cell surface receptors.

Conclusions:

• ATX structure provides insights into its unique enzymatic activity and substrate specificity.
• Understanding ATX-mediated LPA signaling is critical for comprehending its role in diverse biological processes.
• Targeting ATX offers a promising therapeutic strategy for diseases associated with aberrant ATX-LPA signaling.