Golgi stacks

Orci, L., Glick, B. S. and Rothman, J. E. A new type of coated vesicular carrier that appears not to contain clathrin its possible role in protein transport within the Golgi stack. Cell 46 171-184,1986. 

Bonfanti, L., Mironov, A. A. Jr., Martinez-Menarguez, J. A. et al. Procollagen traverses the Golgi stack without leaving the lumen of cisternae evidence for cisternal maturation. Cell 95 993-1003,1998. 

Drug studies demonstrated a requirement that most proteins destined for fast axonal transport traverse the Golgi stacks, where membrane proteins are post-transla-tionally modified, sorted and packaged [9] (Fig. 28-7). This suggests that proteins in fast axonal transport must either pass through the Golgi complex or associate with... 

Removal of the N- and C-terminal propeptides from fully folded procollagens occurs only after transport of procollagens across the Golgi stacks and results in collagen molecules that are then able to assemble into fibrils. C-proteinase activity is possessed by members of the tolloid family of zinc metalloproteinases,... 

Figure 10-8 Current version of protein synthesis and processing via ER, Golgi, and secretory vesicles. CGN, ds-Golgi network C, T, M are the cis, medial, and trans compartments of the Golgi stack TGN, trans Golgi network. Arrows indicate some of the movements of transport vesicles.

Figure 20-8 (A) Electron micrograph showing a transverse section through part of the Golgi apparatus of an early spermatid. Cistemae of the ER, Golgi stacks (S), and vesicles (V) can be seen. Curved arrows point to associated tubules. Magnification X45/000.276 Courtesy of Y. Clermont. (B) Scheme showing functions of endoplasmic reticulum, transfer vesicles, Golgi apparatus, and secretion vesicles in the metabolism of glycoproteins.

Septate desmosome Membranous inclusions Secretory bodies Golgi stack... 

Calcified scales formed inside the Golgi and then extruded have so far only been found in coccolithophorids. In other forms, the matrix is formed in the Golgi but calcification takes place in the cytoplasm. In some cases, the plates of coccolithophorids calcify inside the T-shaped cisternae where the stem is associated with the Golgi stack while the scale is already forming with its future distal surface facing the stack. The scales of coccolithophorids always consist of two layers of a cellulose network of microfibrils radially and concentrically arranged. The outer layer of the scale is made up of acidic polysaccharides and small amounts of protein, probably containing hydroxy-... 

After partial hydrolysis in the gut, dietary fatty acids, monoacylglycerols, phospholipids, and cholesterol are absorbed into the mucosal enterocytes lining the small intestine (Chapter 12). Once within the cell, the lipids are reesterified and form a lipid droplet within the lumen of the smooth endoplasmic reticulum. These droplets consists of triacylglycerol and small amounts of cholesteryl esters and are stabilized by a surface film of phospholipid. At the junction of the smooth and the rough endoplasmic reticulum, the droplet acquires apoproteins B-48, A-I, A-II, and A-IV, which are produced in the lumen of the rough endoplasmic reticulum in the same way as other proteins bound for export. The lipoprotein particle is then transported to the Golgi stacks where further processing yields chylomicrons, which are secreted into the lymph and then enter the blood circulation at the thoracic duct. 

COPI vesicles also carry Golgi-resident proteins from later to earlier compartments In the Golgi stack. 

Orel, L., et al. 1989. Dissection of a single round of vesicular transport sequential intermediates for intercisternal movement in the Golgi stack. Cell 56 357-368. 

Several types of evidence suggest that myosin V also participates In the Intracellular transport of membrane-bounded vesicles. For example, mutations In the myosin V gene In yeast disrupt protein secretion and lead to an accumulation of vesicles In the c rt oplasm. Vertebrate brain tissue Is rich In myosin V, which Is concentrated on Golgi stacks. This association with membranes Is consistent with the effects of myosin V mutations In mice. Such mutations are associated with defects In synaptic transmission and eventually cause death from seizures. Myosin VI also Is Implicated In membrane trafficking of vesicles. 

Rivera, T. Clackson, A. Perrelet, T.H. Sollner, J.E. Rothman, L. Orci, Megavesicles implicated in the rapid transport of intracisternal aggregates across the Golgi stack, Cell 2000, 102, 335-348. 

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