VAMP4- and VAMP7-expressing vesicles are both required for cytotoxic granule exocytosis in NK cells.

ABSTRACT: NK cells eliminate cancer and virus-infected cells through their cytolytic activity. The last step in NK-cell cytotoxicity, resulting in exocytosis of granule content, requires fusion of lytic granules with the plasma membrane. Proteins from the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family mediate membrane fusion events in the cell. Here, we show that NK cells express all members of the R-SNARE subgroup. Two of these R-SNARE proteins, VAMP4 and VAMP7, colocalize with lytic granules during cytotoxic interactions. However, only VAMP7 associates with perforin-containing granules in nonactivated cells, indicating that the two VAMPs have different functions in exocytosis. Using both the tumor NK-cell line YTS and the peripheral NK cells, we show that the

SUBMITTER: Krzewski K 

PROVIDER: S-EPMC3438144 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature