Abstract
The specific vesicle fusion during the vesicular transport is mediated by membrane-associated proteins called SNAREs. Recently, the SNARE proteins have been classified into five classes based on the similarities of the SNARE motif for Qa-SNAREs/Syntaxins, Qb-SNAREs, Qc -SNAREs, R-SNAREs/VAMPs and SNAP-25. We identified 54 SNARE genes (18 Qa-SNAREs/Syntaxins, 11 Qb-SNAREs, 8 Qc-SNAREs, 14 R-SNAREs/VAMPs and 3 SNAP-25) in the Arabidopsis genome. RT-PCR analyses revealed that all SNARE genes were differentially expressed among tissues. In order to characterize the subcellular localization of the SNARE proteins involved in various vesicular transport pathways, we performed a series of transient expression assay by using the GFP (green fluorescent proteins) fused proteins and found 6 ER-localized SNAREs, 9 Golgi apparatus-localized SNAREs, 7 TGN-localized SNAREs, 2 endosome-localized SNAREs, 21 PM-localized SNAREs and 9 vacuole-localized SNAREs. These results predict the possible combination of SNARE molecules in each transport pathway. We discussed the complex post-Golgi transport pathways.
