title: AtSYP51/52 functions diverge in the post-Golgi traffic and differently affect vacuolar sorting.
abstract: Plant sensitive factor attachment protein receptors (SNAREs) encoded by genes of the same sub-family are generally considered as redundant in promoting vesicle-associated membrane fusion events. Nonetheless, the application of innovative experimental approaches highlighted that members of the same gene sub-family often have different functional specificities. In this work, two closely related Qc-SNAREs--the AtSYP51 and the AtSYP52--are compared in their ability to influence different secretory pathways. Their role in the vesicle sorting to the central vacuole has been revised and they were found to have a novel inhibitory function. When transiently overexpressed, the SYP51 and the SYP52 distributed between the TGN and the tonoplast. Our data demonstrate that these SYPs (syntaxin of plants) act as t-SNARE when present on the membrane of TGN/PVC, whereas they behave as inhibitory or interfering SNAREs (i-SNAREs) when they accumulate on the tonoplast. Moreover, the performed functional analysis indicated that the AtSYP51 and the AtSYP52 roles differ in the traffic to the vacuole. The findings are a novel contribution to the functional characterization of plant SNAREs that reveals additional non-fusogenic roles.
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, University of Salento, Campus Ecotekne, 73100 Lecce, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: De Benedictis
authors.forename: Gianluca
authors.initials: G
authors.lastname: Bleve
authors.forename: Marianna
authors.initials: M
authors.lastname: Faraco
authors.forename: Egidio
authors.initials: E
authors.lastname: Stigliano
authors.forename: Francesco
authors.initials: F
authors.lastname: Grieco
authors.forename: Gabriella
authors.initials: G
authors.lastname: Piro
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Dalessandro
authors.forename: Gian Pietro
authors.initials: GP
authors.lastname: Di Sansebastiano
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D015153:Blotting, Western; D002451:Cell Compartmentation; D004705:Endocytosis; D005089:Exocytosis; D005816:Genetic Complementation Test; D006056:Golgi Apparatus / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D021381:Protein Transport; D011523:Protoplasts / Q000378:metabolism; D050765:Qa-SNARE Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011995:Recombination, Genetic / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D012995:Solubility; D014170:Transformation, Genetic; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D050765:Qa-SNARE Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; C584701:syntaxin-51, Arabidopsis; C584702:syntaxin-52, Arabidopsis; D049452:Green Fluorescent Proteins
keywords: Golgi; SNARE; TGN; endocytosis; endosome; i-SNARE; plant endomembranes; protoplast; tonoplast; vacuole