Intracellular localization of SNAP-23 to endosomal compartments

D Chen, SW Whiteheart - Biochemical and biophysical research …, 1999 - Elsevier
Biochemical and biophysical research communications, 1999Elsevier
We have reexamined the intracellular localization of the ubiquitously expressed target
membrane SNAP receptor (t-SNARE), SNAP-23. While SNAP-23 appears on the plasma
membrane, in the cell types examined there is a significant pool associated with endosomal
compartments. Immuno-staining and expression of green fluorescent protein-tagged SNAP-
23, show that it has a punctate, perinuclear localization in HepG2 and HT4 cells. This
distribution overlaps significantly with transferrin receptor and slightly with the late …
We have reexamined the intracellular localization of the ubiquitously expressed target membrane SNAP receptor (t-SNARE), SNAP-23. While SNAP-23 appears on the plasma membrane, in the cell types examined there is a significant pool associated with endosomal compartments. Immuno-staining and expression of green fluorescent protein-tagged SNAP-23, show that it has a punctate, perinuclear localization in HepG2 and HT4 cells. This distribution overlaps significantly with transferrin receptor and slightly with the late endosome/lysosomal protein LAMP-1. The localization of SNAP-23 changes as HepG2 cells polarize. Initially it is concentrated at sites of cell-cell contact and then almost exclusively to the apical (or bile canalicular) domain of the cell. These data are consistent with a role for SNAP-23 in both endosome-plasma membrane trafficking as well as endosome-endosome transport.
Elsevier