Format

Send to

Choose Destination
Glia. 2008 Sep;56(12):1271-84. doi: 10.1002/glia.20696.

Confocal imaging and tracking of the exocytotic routes for D-serine-mediated gliotransmission.

Author information

1
CNRS, Institut de Neurobiologie Alfred Fessard, FRC 2118, Laboratoire de Neurobiologie Cellulaire et Mol├ęculaire, UPR 9040, F-91198 Gif-sur-Yvette, France.

Abstract

D-Serine is an astrocyte-derived regulator for N-methyl-D-aspartate receptors, but the intracellular routes of its trafficking are still largely unknown. Here, we combined confocal microscopy with colocalization quantification to track the astrocytic organelles that store D-serine. We report that D-serine colocalizes with the transfected eGFP-synaptobrevin/VAMP2 and eGFP-cellubrevin/VAMP3, two v-SNAREs of the regulated secretory pathway. No significant colocalization was found with markers of the endosomal sorting and recycling system: EEA1, eGFP-endobrevin/VAMP8, eGFP-TI-VAMP/VAMP7, LAMP1, and CD63. Blockade of vesicular budding with colchicine shows that secretory vesicles import D-serine downstream to the Golgi apparatus. Finally, treatment of astrocytes with the Ca2+-ionophore A23187, glutamate agonists, or bradykinin trigger translocation of synaptobrevin/VAMP2 to the plasma membrane with a concomitant disappearance of D-serine from the regulated secretory pathway. Our results provide morphological evidence for a vesicular storage of D-serine in the regulated secretory pathway and the possible recruitment of these stores by Ca2+ mobilization to release D-serine.

PMID:
18615566
DOI:
10.1002/glia.20696
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center