Unknown

Dataset Information

0

Combinatorial SNARE complexes with VAMP7 or VAMP8 define different late endocytic fusion events.


ABSTRACT: Both heterotypic and homotypic fusion events are required to deliver endocytosed macromolecules to lysosomes and remodel late endocytic organelles. A trans-SNARE complex consisting of Q-SNAREs syntaxin 7, Vti1b and syntaxin 8 and the R-SNARE VAMP8 has been shown by others to be responsible for homotypic fusion of late endosomes. Using antibody inhibition experiments in rat liver cell-free systems, we confirmed this result, but found that the same Q-SNAREs can combine with an alternative R-SNARE, namely VAMP7, for heterotypic fusion between late endosomes and lysosomes. Co-immunoprecipitation demonstrated separate syntaxin 7 complexes with either VAMP7 or VAMP8 in solubilized rat liver membranes. Additionally, overexpression of the N-terminal domain of VAMP7, in cultured fibroblastic cells, inhibited the mixing of a preloaded lysosomal content marker with a marker delivered to late endosomes. These data show that combinatorial interactions of SNAREs determine whether late endosomes undergo homotypic or heterotypic fusion events.

SUBMITTER: Pryor PR 

PROVIDER: S-EPMC1299070 | BioStudies | 2004-01-01

SECONDARY ACCESSION(S): AB040054

REPOSITORIES: biostudies

Similar Datasets

2002-01-01 | S-EPMC1222979 | BioStudies
1000-01-01 | S-EPMC3932887 | BioStudies
2000-01-01 | S-EPMC14922 | BioStudies
1000-01-01 | S-EPMC1413832 | BioStudies
2007-01-01 | S-EPMC1782365 | BioStudies
2000-01-01 | S-EPMC305878 | BioStudies
1000-01-01 | S-EPMC5349786 | BioStudies
2020-01-01 | S-EPMC7144865 | BioStudies
2010-01-01 | S-EPMC2878558 | BioStudies
2016-01-01 | S-EPMC4970327 | BioStudies