考研资料：北京大学细胞生物学第六章基质与内膜下

B. Signal Hypothesis -G.Blobel One that interacts with the ribosome to block further translation;One that binds to the ER membrane (docking protein)The sorting signal of VSV glycoproteins : Asp-X-Gln或 DXEFigure 6-43. The sorting of proteins destined for the apical and basolateral plasma membranes of epithelial cells. When cultured MDCK cells are infected simultaneously with VSV and influenza virus, the VSV glycoprotein is found only on the basolateral membrane, whereas the HA glycoprotein of the influenza virus is found only on the apical membrane. Like these viral proteins, some cellular proteins are sorted directly to the apical membrane and others to the basolateral membrane via specific transport vesicles that bud from the trans-Golgi network. In certain other polarized cells, some apical and basolateral proteins are transported together to the basolateral surface; the apical proteins then move selectively, by endocytosis and transcytosis, to the apical membrane. K. Simons et al., Cell 62:207; K. Mostov et al., JCB. 116:577vStart-transfer Sequence Sar-GDP dissociates from the ERAntibodies is able to block the budding of vesicle from ER but have no effect on vesicle transport from one Golgi compartment to another in mammalian cell.v COPI-coated vasicles transporting Escaped ER resident Proteins Back to the ER.(1)The assembly of a COPI-coat is mediated by ADP-ribosylation factor(ARF), GTP binding protein, which is required for vesicle transfer between cisternae.(2)COPI coated vesicles may select specific cargo. ER is an open prison. Soluble ER protein bear Retrieving signalKDEL(Lys-Asp-Glu-Leu)in mammal and HDEL in yeast, whereas ER membrane proteins bear the signal KKXX .The KDEL receptor present in vesicular tubular clusters and the Golgi apparatus(1)(3) COPI-coated vesicle were first identified by treatment of GTP analogues - COPI-coated vesicle accumulated within the cell and could be isolated by centrifugation.A model for the retrieval of ER resident proteins.The KDEL receptor captures the soluble ER resident proteins and carries them in COPI-coated transport vesicles back to the ER.Neutral pH: dissociate from the KDEL; low pH: binding the KDEL v Clathrin-coated vesicle: Transporting Cargo from the TGN to endosomes, Lysosomes, and plant vacuoles and also move materials from the PM to cytoplasmic compartments along the endocytic pathway.(1)The TGN of Golgi is the Sourse of Clathrin-coated vesicle.(2) Clathrin-coats contain: protein clathrin-which forms a structural scaffold,adaptors- multisubunit,which forms an inner shell. The formation of clathrin-coatedpits in the TGNB. The SNARE Hypothesis for Transport Vesicle Targeting and FusionvSpecificity in vesicle docking and fusion is thought to be attained through specific interactions between specific v-SNARE proteins on the vesicle membranes and t-SNARE proteins on the membranes of the target compartment.vSNAREs are a protein family. There are at least 20 different SNAREs in an animal cell.The role of SNAREs in guiding vesicular transport.The struction of paired SNAREs (the four-helix bundle).The SNAREs responsible for docking synaptic vesicles at the plasma membrane of nerve terminals consist of three proteins.The basic molecular components in eukaryotic cells includev-SNAREs (v-SNAP receptors) on transport vesicles, t-SNAREs(t-SNAP receptors) on target membranes, Rab GTPase, NSF, andseveral SNAPs. SNAPs are soluble NSF attachment proteins.The role of Rab proteins in facilitating the docking of transport vesicles.GEF in donor membrane;GTP binding alters the conformation of Rab, exposing its covalently attached lipid group and helps anchoring;Rab and Rab effectors help the vesicle dock and pairing of the v-and t-SNAREs;GDI: GDP dissociation inhibitor.kinesin dyneinC. Motor prote