RRC ID 6676
著者 Bogdanovic A, Bennett N, Kieffer S, Louwagie M, Morio T, Garin J, Satre M, Bruckert F.
タイトル Syntaxin 7, syntaxin 8, Vti1 and VAMP7 (vesicle-associated membrane protein 7) form an active SNARE complex for early macropinocytic compartment fusion in Dictyostelium discoideum.
ジャーナル Biochem J
Abstract The macropinocytic pathway in Dictyostelium discoideum is organized linearly. After actin-driven internalization, fluid material passes sequentially from endosomes to lysosomes, where molecules are degraded and absorbed. Residual material is exocytosed via post-lysosomal compartments. Syntaxin 7 is a SNARE (soluble N -ethylmaleimide-sensitive fusion protein attachment protein receptor) protein that is present and active in D. discoideum endosomes [Bogdanovic, Bruckert, Morio and Satre (2000) J. Biol. Chem. 275, 36691-36697]. Here we report the identification of its main SNARE partners by co-immunoprecipitation and MS peptide sequencing. The syntaxin 7 complex contains two co-t-SNAREs [Vti1 (Vps10p tail interactor 1) and syntaxin 8] and a v-SNARE [VAMP7 (vesicle-associated membrane protein 7)] (where t-SNAREs are SNAREs of the target compartment and v-SNAREs are SNAREs present in donor vesicles). In endosomes and in vitro, syntaxin 7, Vti1 and syntaxin 8 form a complex that is able to bind VAMP7. Antibodies to syntaxin 8 and a soluble recombinant VAMP7 fragment both inhibit in vitro reconstituted D. discoideum endosome fusion. The lysosomal content of syntaxin 7, Vti1, syntaxin 8 and VAMP7 is low compared with that in endosomes, implying a highly active recycling or retention mechanism. A likely model is that VAMP7 is a v-SNARE present on vesicles carrying lysosomal enzymes, and that the syntaxin 7-Vti1-syntaxin 8 t-SNARE complex is associated with incoming endocytic material.
巻・号 368(Pt 1)
ページ 29-39
公開日 2002-11-15
DOI 10.1042/BJ20020845
PII BJ20020845
PMID 12175335
PMC PMC1222979
MeSH Amino Acid Sequence Animals Carrier Proteins / metabolism* Dictyostelium / metabolism* Endosomes / metabolism Humans Membrane Fusion Membrane Proteins / metabolism* Molecular Sequence Data Pinocytosis Protozoan Proteins / metabolism* Qa-SNARE Proteins Qb-SNARE Proteins R-SNARE Proteins SNARE Proteins Vesicular Transport Proteins*
IF 4.097
引用数 32
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
細胞性粘菌