Biology 2382B Lecture Notes - Lecture 5: Copii, Protein Targeting, Copi
Document Summary
Golgi complex proteins, and mis-sorted rer proteins from golgi to er. Processing and sorting of proteins (secreted, membrane, lysosomal) Mutation in cftr protein which is synthesized in rer. F508 prevents normal transport by blocking packaging into copii vesicles. Absence of one or more lysosomal enzymes resulting in accumulation of undegraded material in lysosomes. Inclusion-cell (i-cell) disease; absence of glcnac phosphotransferase; m6p signal doesn"t get put on in golgi. Gtp binding protein to patch of donor membrane. Coat proteins then bind to cytosolic domain of membrane cargo proteins (copii recognizes sorting signal, dxe) Coat gives curvature to membrane and acts as filter to determine which proteins admitted to vesicle. Located mainly in cis-golgi network, and in copii, copi. Fuse with golgi via v-snare and t-snare interactions. Binds proteins bearing kdel sorting signal and returns them to rer. Kdel receptor has kkxx sorting signal which binds to. Binding affinity of kdel receptor is sensitive to ph.