BIO130H1 Lecture 6: Second Section Lecture 6

• School: UTSG
• Department: Biology
• Course: BIO130H1
• Professor: Jane Mitchell

Document Summary

Transmembrane protein secretion path: cytosol er golgi secretory vesicle plasma membrane (pm)/exocytosis. Golgi apparatus: glycosylates proteins and lipids, glycosylation: addition of glycans (carbohydrate) to organic molecules, cis face faces er. Protein glycosylation: begins in er, single type of oligosaccharide attached to protein, oligosaccharide modification occurs in golgi, modifications occurs in lumen of organelles. Each protein inserted into er in specific orientation. Protein asymmetry in er insertion is maintained throughout transport process. Protein side that faces cytosol always faces cytosol. Protein side that faces lumen always faces lumen, extracellular fluid at pm: detergents/other removal processes can change protein facing orientation. Endosomes: membrane bound organelle, carries materials newly ingested by endocytosis. Lysosomes: sac of digestive enzymes, that are delivered as vesicles er/golgi, degrade various materials received from endosomes. Lysosomes can fuse with endosomes to form endolysosome. 15/12: within endolysosome, lysosome proteins degrade material in endosome. Lysosome proteins: hydrolytic, break apart molecules though hydrolysis.