Regulated endosomal trafficking of Diacylglycerol lipase alpha (DAGLα) generates distinct cellular pools; implications for endocannabinoid signaling

TY - JOUR

T1 - Regulated endosomal trafficking of Diacylglycerol lipase alpha (DAGLα) generates distinct cellular pools; implications for endocannabinoid signaling

AU - Zhou, Ya

AU - Howell, Fiona Victoria

AU - Glebov, Oleg

AU - Albrecht, David

AU - Williams, Gareth

AU - Doherty, Patrick

PY - 2016/10/1

Y1 - 2016/10/1

N2 - Diacylglycerol lipase alpha (DAGLα) generates the endocannabinoid (eCB) 2- arachidonylglycerol (2-AG) that regulates the proliferation and differentiation of neural stem cells and serves as a retrograde signaling lipid at synapses. Nothing is known about the dynamics of DAGLα expression in cells and this is important as it will govern where 2-AG can be made and released. We have developed a new construct to label DAGLα at the surface of live cells and follow its trafficking. In hippocampal neurons a cell surface pool of DAGLα co-localizes with Homer, a postsynaptic density marker. This surface pool of DAGLα is dynamic, undergoing endocytosis and recycling back to the postsynaptic membrane. A similar cycling is seen in COS-7 cells with the internalized DAGLα initially transported to EEA1 and Rab5-positive early endosomes via a clathrin-independent pathway before being transported back to the cell surface. The internalized DAGLα is present on reticular structures that co-localize with microtubules. Importantly, DAGLα cycling is a regulated process as inhibiting PKC results in a significant reduction in endocytosis. This is the first description of DAGLα cycling between the cell surface and an intracellular endosomal compartment in a manner that can regulate the level of the enzyme at the cell surface.

AB - Diacylglycerol lipase alpha (DAGLα) generates the endocannabinoid (eCB) 2- arachidonylglycerol (2-AG) that regulates the proliferation and differentiation of neural stem cells and serves as a retrograde signaling lipid at synapses. Nothing is known about the dynamics of DAGLα expression in cells and this is important as it will govern where 2-AG can be made and released. We have developed a new construct to label DAGLα at the surface of live cells and follow its trafficking. In hippocampal neurons a cell surface pool of DAGLα co-localizes with Homer, a postsynaptic density marker. This surface pool of DAGLα is dynamic, undergoing endocytosis and recycling back to the postsynaptic membrane. A similar cycling is seen in COS-7 cells with the internalized DAGLα initially transported to EEA1 and Rab5-positive early endosomes via a clathrin-independent pathway before being transported back to the cell surface. The internalized DAGLα is present on reticular structures that co-localize with microtubules. Importantly, DAGLα cycling is a regulated process as inhibiting PKC results in a significant reduction in endocytosis. This is the first description of DAGLα cycling between the cell surface and an intracellular endosomal compartment in a manner that can regulate the level of the enzyme at the cell surface.

U2 - 10.1016/j.mcn.2016.08.011

DO - 10.1016/j.mcn.2016.08.011

M3 - Article

SN - 1044-7431

JO - Molecular and Cellular Neuroscience

JF - Molecular and Cellular Neuroscience

ER -