Cellular Vesicle

Abstract: The cellular vesicle is a fluid-filled structure separated from the surrounding environment by a biological membrane. Here, we isolated nanovesicles (NVs) from the juice of clementines using a discontinuous density gradient ultracentrifugation method. To gain information about the protein content of vesicles, mass spectrometry-based organelle proteomics and bioinformatics were applied to the exosome-like vesicle fraction isolated in the 1 mol/L sucrose/D2O cushion. Analysis of 1018 identified proteins revealed a highly complex mixture of different intra, extracellular and artificially-formed vesicle populations. In particular, clathrin-coated vesicles were significantly expressed in this sample. Membrane transporters are significantly represented in clementines nanovesicles. We have found 162 proteins associated with the transport Gene Ontology term (GO: 0006810) which includes; 71 transmembrane transport related, 53 vesicle mediated and 50 intracellular transporters. Platellin-3 like carrier protein containing a Sec14 domain is known to have a role in plant-virus interaction and that is one of the most abundant proteins in our dataset. The presence of transmembrane transporters like ATPases, aquaporins, ATP Binding Cassette (ABC) transporters and tetraspanins, regulators of protein trafficking suggests that nanovesicles of clementines can actively interact with their environment in a controlled way.

Abstract: The invention concerns a novel method for sensitising antigen-presenting cells, novel means for implementing the method, and novel membrane vesicles with immunogenic properties. The invention concerns particularly texosomes (vesicles derived from tumour cells ) and dexosomes (vesicles derived from dendritic cells loaded with antigens or not), and their use for vectoring and presenting antigens in vitro or in vivo and methods or compositions for treating cancers, infectious, parasitic or autoimmune diseases in particular.

Abstract: Multiple C2 domains transmembrane protein 1 (MCTP1) contains two transmembrane regions and three C2 domains of high Ca(2+)-binding affinity. Single-nucleotide polymorphism (SNP) of human MCTP1 gene is reportedly associated with bipolar disorder, but expression and function of MCTP1 in the CNS is still largely unknown. We cloned rat MCTP1 isoforms, and studied expression of MCTP1 transcript and protein in the CNS. Subcellular distribution and functional roles of MCTP1 were investigated in cultured primary neurons or PC12 cells by over-expression, cell imaging, and flow cytometry. MCTP1 immunostaining was seen in both CNS neuronal cell bodies and processes, especially in the hippocampus, dentate gyrus, medial habenular nucleus, amygdala, and selected cerebral and cerebellar cortical areas/layers. Under an electron microscope, MCTP1 immunoreactivity was observed on vesicles in neuronal cell bodies and pre-synaptic axon terminals. In cultured primary neurons and PC12 cells MCTP1 was detected on selected populations of secretory vesicles and endosomes. MCTP1 over-expression significantly inhibited neuronal transferrin endocytosis, secretory vesicle retrieval, cell migration, and oxidative stress from glutamate toxicity. Thus MCTP1 might be involved in regulating endocytic recycling of specific CNS neurons and synapses. MCTP1 abnormality might cause altered synaptic vesicle recycling, and thereby lead to vulnerability to neuropsychiatric diseases.