Vesicle mediation

Clathrin-coated vesicles mediate transport within the late secretory and the endocytic pathways. Their major coat constituents are clathrin and various adaptor complexes. 

COPI vesicles mediate anterograde transport from the intermediate compartment to the Golgi, transport within the Golgi apparatus and retrograde transport back from the Golgi to the ER by the recruitment of soluble... 

Synaptic vesicles mediate the release of small molecules other than classical neurotransmitters and neuropeptides. Of these, zinc and ATP are the best characterized. NMDA and GABA receptors contain binding sites for zinc, and zinc exerts a direct effect on... 

Most probably the presence of pardaxin pores alters the structure of the bilayer resulting in aggregation of phosphatidylserine vesicles mediated by contact but not by partial merging of their membranes. 

De Jong EK, Dijkstra IM, Hensens M, et al. Vesicle-mediated transport and release of CCL21 in endangered neurons a possible explanation for microglia activation remote from a primary lesion. J Neurosci 2005 25 7548-7557. 

Clathrin-coated vesicles mediate transport from the Golgi apparatus to endosomes, and from the plasma membrane to endosomes. A multi-subunit protein, clath-rin, constitutes the major protein of this vesicle type (see Ch. 2). Clathrin is composed of three large and three small polypeptide chains, which assemble to form a triskelion (Fig. 9-2). Regulatory mechanisms control the assembly and formation of a convex, polyhexa-pentagonal basketlike structure by these triskelions [5], This structure is responsible for the formation of coated pits on the cytosolic face of plasma membranes. 

COPI-coated vesicles mediate intra-Golgi transport and Golgi to ER retrograde transport. The coats of these vesicles do not show the geometric forms seen with clathrin coats and have a more complex protein composition [3]. Coat protein purification first lead to the identification of a complex composed of seven individual coat-protein subunits, known as COPI or coatomer. Some of these subunits bear a sequence similarity to clathrin adaptors. In addition, there is a small GTP-binding protein, Arfl, present on COPI-coated vesicles. 

Pryer, N.K., Wuestehube, L.J., Schekman, R. (1992) Vesicle mediated protein sorting. Annu. Rev. Biochem 61, 471-516. 

Pryer, N. K Wuestehube, L. J., and Schekman, R. (1992) Vesicle-Mediated Protein Sorting, Annual Review of Biochemistry, 61,471-516. 

Tuckey RC, Headlam MJ, Bose HS, Miller WL Transfer of cholesterol between phospholipid vesicles mediated by the steroidogenic acute regulatory protein (StAR). f Biol Chem 277 47123-47128,2002. 

Crawford, XM. Role of vesicle-mediated transport pathways in hepatocellular bile secretion. Semin. Liver Dis. 1996 16 169-189... 

The fusion of membranes at several stages in the vesicle-mediated transport of materials between Golgi compartments requires a specific protein known as the N-ethylmaleimide-sensitive fusion protein... 

Surfactant vesicle-mediated delivery of DNA vaccines via the subcutaneous route. Int J Pharm 284 31-41... 

S. Tavema, G. Ghersi, A. Ginestra, S. Rigogliuso, S. Pecorella, G. Alaimo, F. Saladino, V. Dolo, P. Dell Era, A. Pavan, et al. Shedding of membrane vesicles mediates fibroblast growth factor-2 release from cells, J Biol Chem 278, 51911-51919 (2003). 

In a classic paper, Snapper synthesized an ilimaquinone-agarose-affinity resin (30), which was incubated with homogenized bovine liver and then washed extensively.93 Proteins retained by the resin were separated by gel electrophoresis, yielding six main protein bands. Amino acid sequencing of these bands revealed three proteins involved in the activated methyl cycle — SAHase, S-adenosylmethionine synthetase (SAM synthetase), and catechol-O-methyltransferase (COMT) — as well as three unrelated proteins. Subsequent enzymatic assays established that ilimaquinone is a competitive inhibitor of SAHase, but has little effect on the activity of SAM synthetase or COMT. The authors noted that a consequence of SAHase inhibition would be the intracellular accumulation of SAH, which is a potent feedback inhibitor of methyltransferases. These results support the assertion that methylation events play an important role in cellular secretory events and vesicle-mediated processes. The study also highlighted the problem of nonspecific interactions as only one of the six isolated proteins was shown to interact in any way with the natural product. 

For many metals and semi-metals and even for an element such as cadmium, it has recently been described that volatilization can be obtained by vesicle mediation. Indeed, surfactants are able to organize reactants at a molecular level, by which chemical generation of volatile species is enhanced. It was shown, by Sanz-Medel et al. [169], that by adding micelles or vesicles to cadmium solutions it is possible to generate volatile CdH2 with a high efficiency. This volatile compound can even be transported to a measurement cell where a cold vapor of cadmium can be measured. 

Hsu HH, Morris DC, Davis L et al (1993) In vitro Ca deposition by rat manix vesicles is the membrane association of alkaline phosphatase essential for matrix vesicle-mediated calcium deposition Int J Biochem 25 1737-1742... 

Roberts S, Narisawa S, Harmey D et al (2007) Functional involvement of PHOSPHOl in matrix vesicle-mediated skeletal mineraUzation. J Bone Miner Res 22 617-627... 

In two variations of this basic procedure, transport of VSV G protein is monitored by different techniques. Studies using both of these modern trafficking assays and Palade s early experiments all came to the same conclusion in mammalian cells vesicle-mediated transport of a protein molecule from its site of synthesis on the rough ER to its arrival at the plasma membrane takes from 30 to 60 minutes. 

CORN Vesicles Mediate Transport from the ER to the Golgi... 

COPI Vesicles Mediate Retrograde Transport within the Golgi and from the Golgi to the ER... 

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