Development of an activity-based probe for autotaxin

Area of Science:

• Biochemistry
• Enzymology
• Chemical Biology

Background:

• Autotaxin (ATX), also known as ecto-nucleotide pyrophosphatase/phosphodiesterase 2 (ENPP2), is a secreted enzyme.
• ATX hydrolyzes lysophosphatidylcholine to produce lysophosphatidic acid (LPA), a key lipid mediator involved in cell proliferation and migration.
• ATX is implicated in tumor progression and inflammatory diseases, suggesting its potential as a biomarker.

Purpose of the Study:

• To develop a novel fluorescent activity-based probe (ABP) for detecting and quantifying ATX enzymatic activity.
• To characterize the specificity and utility of the developed ABP in biological samples.

Main Methods:

• Design and synthesis of a lysophospholipid-based ABP incorporating a reactive trapping moiety and a Cy5 fluorescent dye.
• Testing the probe's reactivity and specificity against purified ATX isoforms.
• Evaluating the probe's ability to compete with known ATX inhibitors.
• Assessing the probe's performance in measuring ATX activity in biological fluids like plasma.

Main Results:

• The developed ABP specifically and covalently binds to the active site of all three known ATX isoforms.
• The probe demonstrates competition with established small-molecule ATX inhibitors, confirming its binding mechanism.
• The ABP successfully quantifies ATX activity in plasma samples.
• The fluorescent dye (Cy5) allows for direct visualization and measurement of active ATX.

Conclusions:

• A novel, specific fluorescent activity-based probe for autotaxin has been successfully developed.
• This probe is a valuable tool for monitoring ATX activity in biological fluids.
• The reporter facilitates inhibitor screening, potentially aiding in the development of therapeutics for ATX-related diseases.