ABHD6 selectively controls Gq-dependent increases in 2-AG production

Singh, S.; Sarroza, D.; English, A.; Whittington, D.; Dong, A.; van der Stelt, M.; Li, Y.; Zweifel, L.; Bruchas, M. R.; Land, B. B.; Stella, N.

doi:10.1101/2022.05.18.492553

bioRxiv · 10.1101/2022.05.18.492553

ABHD6 selectively controls Gq-dependent increases in 2-AG production

Singh, S.·Sarroza, D.·English, A.·Whittington, D.·Dong, A.·van der Stelt, M.·Li, Y.·Zweifel, L.·Bruchas, M. R.·Land, B. B.·Stella, N.

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Abstract

The most abundant endocannabinoid (eCB) in the brain, 2-arachidonoyl glycerol (2-AG), is hydrolyzed by /{beta}-hydrolase domain containing 6 (ABHD6); yet how ABHD6 controls stimuli-dependent increases in 2-AG production is unknown. To explore this question, we leveraged the recently developed 2-AG sensor, GRABeCB2.0, and found that stimulation of Neuro2a cells in culture with bradykinin (BK) acting at metabotropic B2K receptors and ATP acting at ionotropic P2X7 receptors led to differential increases in 2-AG levels. B2K triggered increases in 2-AG levels via diacylglycerol lipase (DAGL), and this mechanism was potentiated by increases in intracellular calcium and ABHD6 inhibition. By contrast, P2X7-triggered increases in 2-AG levels were dependent on DAGL and extracellular calcium but unaffected by ABHD6 inhibition. Thus, ABHD6 preferentially regulates metabotropic-dependent increases in 2-AG levels over ionotropic-dependent increases in 2-AG levels. Our study indicates that ABHD6 selectively controls stimuli-dependent increases in 2-AG production and emphasizes its specific role in eCB signaling.

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Singh, S., Sarroza, D., English, A., Whittington, D., Dong, A., van der Stelt, M., Li, Y., Zweifel, L., Bruchas, M. R., Land, B. B., Stella, N.. 2022-05-19. ABHD6 selectively controls Gq-dependent increases in 2-AG production. https://doi.org/10.1101/2022.05.18.492553

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