Cis Golgi is closest to ER. Modify carbohydrates on proteins.All starts with a common sugar branching structure.It is in the different stages of the Golgi that the common core can be modified.There is a variety of different modifications that can occur in this process.As the vesicle moves further and further away from the nucleus, new enzymes get expressed. Enzymes change as the cistrene moves away from the nucleus.All the cistrene that have gone through this assembly line now come into the trans-Golgi network. It is like a sorting station.Late endosome fuses with lysosome.Clathrin vesicles go from the trans-Golgi network to the endosome and used for endocytosis.AP complexes are our coat proteins. The AP stands for adaptor proteins. They have binding cites for sorting signals and are used to bind to specific cargo proteins. Have 2 coats, the traditional coat and then a coat of clathrin. Clathrin is a tri-skeleton structure. When it all polymerizes together, it looks like a soccer ball with a lattice cage that surrounds the AP proteins.There is the membrane which is a lipid bilayer. Then the AP coat of proteins. Then clathrin coat.Dynamin is used to pinch off clathrin vesicles. It uses GTP hydrolysis for energy.Sorting signals used with COPI, COPII, and clathrin vesicles. If protein does not have a sorting signal, it will not go anywhere.Di-acidic are COPII.KDEL are for COPI.Know M. 6-Phosphate, Am-Pox, and Try-X-X.Mannose 6-phosphate receptors predominantly try to get proteins from the trans-Golgi network into the endosome.If you add on a Mannose 6-phosphate group in the Golgi, that tags a protein to go into the endosome. If the protein does not have that tag, it will not go to the endosome. Ensures that specific proteins go into the endosome and not others. The Mannose 6-phosphate structure makes use of affinity changes due to pH differences.In the Golgi, the pH is 6.5. In the endosome, the pH is about 5. The Mannose 6-phosphate has very high affinity at higher pH levels. Once this goes into the endosome, the affinity of Mannose 6-phosphate decreases causing the protein to be released.The plasma membrane has specific receptors for what you want to bring in, such as iron. The receptors bind to molecules, form clathrin vesicles. AP coat is present along with clathrin coat on outside. Dynamin is needed in order to push off the vesicle. Then you have a clathrin vesicle inside the cell that will fuse with the endosome.Iron is transported in the blood by being bound to transferrin. Transferrin is a carrier bound protein for iron. Without iron, it is called apotransferrin.Any cell that needs to bring in iron is going to express on the plasma membrane that it needs iron. The transferrin comes along and binds to the receptor. The receptor is bond to transferrin, there is a conformational change in the protein that exposes the sorting signal. The signal is YTRF, which is the Tyr-XX. The sorting signal is only revealed once bound. The sorting signal can now be used by AP2 proteins will bind to the YTRF sorting signal. The first layer of the coat, which holds all of the iron, polymerizes the clatherin. Dynamin is used. Fuses with endosome. Again relying on pH differences so that at the reduced pH of 5, the iron will get released.Vesicles move by being recruited, bound to a protein, budded off, and then uncoated.02/24/2015Cis Golgi is closest to ER. Modify carbohydrates on proteins. All starts with a common sugar branching structure. It is in the different stages of the Golgi that the common core can be modified. There is a variety of different modifications that can occur in this process.As the vesicle moves further and further away from the nucleus, new enzymes get expressed. Enzymes change as the cistrene moves away from the nucleus. All the cistrene that have gone through this assembly line now come into the trans-Golgi network. It is like a sorting station. Late endosome fuses with lysosome. Clathrin vesicles go from the trans-Golgi network to the endosome and used for endocytosis. AP complexes are our coat proteins. The AP stands for adaptor proteins. They have binding cites for sorting signals and are used to bind to specific cargo proteins. Have 2 coats, the traditional coat and then a coat of clathrin. Clathrin is a tri-skeleton structure. When it all polymerizes together, it looks like a soccer ball with a lattice cage that surrounds the AP proteins. There is the membrane which is a lipid bilayer. Then the AP coat of proteins. Then clathrin coat. Dynamin is used to pinch off clathrin vesicles. It uses GTP hydrolysis forenergy. Sorting signals used with COPI, COPII, and clathrin vesicles. If protein does not have a sorting signal, it will not go anywhere. Di-acidic are COPII.KDEL are for COPI.Know M. 6-Phosphate, Am-Pox, and Try-X-X.Mannose 6-phosphate receptors predominantly try to get proteins fromthe trans-Golgi network into the endosome. If you add on a Mannose 6-phosphate group in the Golgi, that tags a protein to go into the endosome. If the protein does not have that tag, it will not go to the endosome. Ensures that specific proteins go into the endosomeand not others. The Mannose 6-phosphate structure makes use of affinity changes due to pH differences.In the Golgi, the pH is 6.5. In the endosome, the pH is about 5. The Mannose 6-phosphate has very high affinity at higher pH levels. Once this goes into the endosome, the affinity of Mannose 6-phosphate decreases causing the protein to be released. The plasma membrane has specific receptors for what you want to bring in, such as iron. The receptors bind to molecules, form clathrin vesicles.AP coat is present along with clathrin coat on outside. Dynamin is needed in order to push off the vesicle. Then you have a clathrin vesicle inside the cell that will fuse with the endosome. Iron is transported in the blood by being bound to transferrin. Transferrin is a carrier bound protein for iron. Without iron, it is called apotransferrin. Any cell that needs to bring in iron is going to express on the plasma membrane that it needs iron. The transferrin comes along and binds to the receptor. The receptor is bond to transferrin, there is a conformational change in the protein that exposes the sorting signal. The signal is YTRF, which is the Tyr-XX. The sorting signal is only revealed once bound. The sorting signal can now be used by AP2 proteins will bind to the YTRF