AtSYP51/52 Functions Diverge in the Post-Golgi Traffic and Differently Affect Vacuolar Sorting  

作　　者：Maria De Benedictis Gianluca Bleve Marianna Faraco Egidio Stigliano Francesco Grieco Gabriella Piro Giuseppe Dalessandro Gian Pietro Di Sansebastiano 

机构地区：[1]Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, University of Salento, Campus Ecotekne, 73100 Lecce, Italy [2]Present address: Dipartimento di Bioscienze, Universita degli Studi di Parma, Parco Area delle Scienze, 11/A, 43124 Parma, Italy [3]Institute of Science of Food Production, National Research Council, via Provinciale Lecce-Monteroni, 73100 Lecce, Italy [4]Laboratory of Cell and Molecular Biology, University of Neuchatel, Rue Emile-Argand 11, CP 158, 2009 Neuchatel, Switzerland

出　　处：《Molecular Plant》2013年第3期916-930,共15页分子植物（英文版）

摘　　要：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.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.

关 键 词：endocytosis ENDOSOME Golgi i-SNARE plant endomembranes protoplast SNARE TGN TONOPLAST vacuole. 

分 类 号：Q942[生物学—植物学] Q189