The role of SNARE [soluble NSF (N-ethylmaleimide-sensitive factor) accessory protein receptor] protein in cellular trafficking, membrane fusion and vesicle release in synaptic nerve terminals is described. The purpose...The role of SNARE [soluble NSF (N-ethylmaleimide-sensitive factor) accessory protein receptor] protein in cellular trafficking, membrane fusion and vesicle release in synaptic nerve terminals is described. The purpose of this review is to highlight the role of SNAREs in vital inflammatory conditions in maturing dendritic cells in order to retain the capacity to present new antigens together with altered cytokine secretory functions. This role of SNAREs can be used as novel targets for therapy in inflammatory diseases. The essential mechanism of SNAREs proteins for regulation of tumour formation through multiple signals and transportation pathways is also discussed. Finally, this review summarizes the current knowledge of SNARE proteins in regulating endocytosis in cancer cells and the possible therapeutic applications related to the pathogenesis of tumor formation.展开更多
The production and secretion of antibodies by human plasma cells(PCs)are two essential processes of humoral immunity.The secretion process relies on a group of proteins known as soluble N-ethylmaleimide-sensitive fact...The production and secretion of antibodies by human plasma cells(PCs)are two essential processes of humoral immunity.The secretion process relies on a group of proteins known as soluble N-ethylmaleimide-sensitive factor attachment protein receptors(SNAREs),which are located in the plasma membrane(t-SNAREs)and in the antibody-carrying vesicle membrane(v-SNARE),and mediate the fusion of both membranes.We have previously shown that SNAP23 and STX4 are the t-SNAREs responsible for antibody secretion.Here,using human PCs and antibody-secreting cell lines,we studied and characterized the expression and subcellular distribution of vesicle associated membrane protein(VAMP)isoforms,demonstrating that all isoforms(with the exception of VAMP1)are expressed by the referenced cells.Furthermore,the functional role in antibody secretion of each expressed VAMP isoform was tested using siRNA.Our results show that VAMP2 may be the v-SNARE involved in vesicular antibody release.To further support this conclusion,we used tetanus toxin light chain to cleave VAMP2,conducted experiments to verify co-localization of VAMP2 in antibody-carrying vesicles,and demonstrated the coimmunoprecipitation of VAMP2 with STX4 and SNAP23 and the in situ interaction of VAMP2 with STX4.Taken together,these findings implicate VAMP2 as the main VAMP isoform functionally involved in antibody secretion.展开更多
Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within th...Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within the cell and from the cell into the apoplast. To investigate a putative role of vesicle fusion in this pro- cess, we used Agrobacterium tumefaciens-mediated transient coexpression in Nicotiana benthamiana of an MtVAMP721e-RNAi construct （Vi） with either a caryophyllene synthase or a linalool synthase, respec- tively. Headspace analysis of the leaves showed that caryophyllene or linalool emission increased about five-fold when N. benthamiana VAMP72 function was blocked. RNA sequencing and protein ubiquitination analysis of the agroinflltrated N. benthamiana leaf extracts suggested that increased terpene emissions may be attributed to proteasome malfunction based on three observations： leaves with TPS＋Vi showed （1） a higher level of a DsRed marker protein, （2） a higher level of ubiquitinated proteins, and （3） coordinated induced expression of multiple proteasome genes, presumably caused by the lack of proteasome- mediated feedback regulation. However, caryophyllene or linalool did not inhibit proteasome-related pro- tease activity in the in vitro assays. While the results are not conclusive for a role of vesicle fusion in terpene transport, they do show a strong interaction between inhibition of vesicle fusion and ectopic expression of certain terpenes. The results have potential applications in metabolic engineering.展开更多
文摘The role of SNARE [soluble NSF (N-ethylmaleimide-sensitive factor) accessory protein receptor] protein in cellular trafficking, membrane fusion and vesicle release in synaptic nerve terminals is described. The purpose of this review is to highlight the role of SNAREs in vital inflammatory conditions in maturing dendritic cells in order to retain the capacity to present new antigens together with altered cytokine secretory functions. This role of SNAREs can be used as novel targets for therapy in inflammatory diseases. The essential mechanism of SNAREs proteins for regulation of tumour formation through multiple signals and transportation pathways is also discussed. Finally, this review summarizes the current knowledge of SNARE proteins in regulating endocytosis in cancer cells and the possible therapeutic applications related to the pathogenesis of tumor formation.
基金This work was supported by grants from the Spanish National Institute of Health‘Carlos III’(FIS-PI1101091,FIS-PI071075)from Plan Nacional I+D+i 2008-2011 from Fondos Europeos de Desarrollo Regional(FEDER)the Consejería de Innovación,Ciencia y Empresa-Junta de Andalucía(P09-CTS-5445)to AC-C and an ASPiRE grant from Ball State University(Indiana,USA)to MK-W.
文摘The production and secretion of antibodies by human plasma cells(PCs)are two essential processes of humoral immunity.The secretion process relies on a group of proteins known as soluble N-ethylmaleimide-sensitive factor attachment protein receptors(SNAREs),which are located in the plasma membrane(t-SNAREs)and in the antibody-carrying vesicle membrane(v-SNARE),and mediate the fusion of both membranes.We have previously shown that SNAP23 and STX4 are the t-SNAREs responsible for antibody secretion.Here,using human PCs and antibody-secreting cell lines,we studied and characterized the expression and subcellular distribution of vesicle associated membrane protein(VAMP)isoforms,demonstrating that all isoforms(with the exception of VAMP1)are expressed by the referenced cells.Furthermore,the functional role in antibody secretion of each expressed VAMP isoform was tested using siRNA.Our results show that VAMP2 may be the v-SNARE involved in vesicular antibody release.To further support this conclusion,we used tetanus toxin light chain to cleave VAMP2,conducted experiments to verify co-localization of VAMP2 in antibody-carrying vesicles,and demonstrated the coimmunoprecipitation of VAMP2 with STX4 and SNAP23 and the in situ interaction of VAMP2 with STX4.Taken together,these findings implicate VAMP2 as the main VAMP isoform functionally involved in antibody secretion.
文摘Plants produce numerous terpenes and much effort has been dedicated to the identification and charac- terization of the terpene biosynthetic genes. However, little is known about how terpenes are transported within the cell and from the cell into the apoplast. To investigate a putative role of vesicle fusion in this pro- cess, we used Agrobacterium tumefaciens-mediated transient coexpression in Nicotiana benthamiana of an MtVAMP721e-RNAi construct （Vi） with either a caryophyllene synthase or a linalool synthase, respec- tively. Headspace analysis of the leaves showed that caryophyllene or linalool emission increased about five-fold when N. benthamiana VAMP72 function was blocked. RNA sequencing and protein ubiquitination analysis of the agroinflltrated N. benthamiana leaf extracts suggested that increased terpene emissions may be attributed to proteasome malfunction based on three observations： leaves with TPS＋Vi showed （1） a higher level of a DsRed marker protein, （2） a higher level of ubiquitinated proteins, and （3） coordinated induced expression of multiple proteasome genes, presumably caused by the lack of proteasome- mediated feedback regulation. However, caryophyllene or linalool did not inhibit proteasome-related pro- tease activity in the in vitro assays. While the results are not conclusive for a role of vesicle fusion in terpene transport, they do show a strong interaction between inhibition of vesicle fusion and ectopic expression of certain terpenes. The results have potential applications in metabolic engineering.
