title: Selective control of SNARE recycling by Golgi retention.
abstract: Two distinct sets of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) catalyze membrane fusion in the cis-Golgi and trans-Golgi. The mechanism that controls Golgi localization of SNAREs remains largely unknown. Here we tested three potential mechanisms, including vesicle recycling between the Golgi and the endoplasmic reticulum, partitioning in Golgi lipid microdomains, and selective intra-Golgi retention. Recycling rates showed a linear relationship with intra-Golgi mobility of SNAREs. The cis-Golgi SNAREs had higher mobility than intra-Golgi SNAREs, whereas vesicle SNAREs had higher mobility than target membrane SNAREs. The differences in SNARE mobility were not due to preferential partitioning into detergent-resistant membrane microdomains. We propose that intra-Golgi retention precludes entropy-driven redistribution of SNAREs to the endoplasmic reticulum and endocytic compartments.
authors.affiliation: Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Fukasawa
authors.forename: Anda
authors.initials: A
authors.lastname: Cornea
authors.forename: Oleg
authors.initials: O
authors.lastname: Varlamov
mesh_terms: D000818:Animals; D006056:Golgi Apparatus / Q000378:metabolism*; D006801:Humans; D050600:SNARE Proteins / Q000378:metabolism*
chemical_list: D050600:SNARE Proteins
keywords: Dynamic equilibrium; ER; Endoplasmic reticulum; Entropy; Golgi; Golgi tether; Homotypic fusion; Lipid raft; Membrane fusion; Recycling; Retention; SNARE; Vesicle; i-SNARE