BE 359 Ch.14 Vesicular Traffic, Secretion, and Endocytosis

labels

various ____________ enable tracking protein movement through the secretory pathway to different destinations

sensitive secretory

components required for intracellular protein trafficking have been identified by analysis of yeast temperature-_______________ ________________ (sec) mutants

cell free

________-________ assays for intercompartmental protein transport have defined individual steps of the secretory pathway

transport vesicles

secretory and endocytic pathway protein trafficking, unifying principle: ____________ _____________ transport membrane and soluble proteins from one membrane-bounded compartment to another

secretory and endocytic

overview of the _______________ and ______________ pathways of protein sorting

collect

protein sorting, transport vesicles: __________ cargo proteins in membrane budding from a donor compartment

deliver

protein sorting, transport vesicles: _________ deliver cargo proteins to the next compartment by fusing with the target membrane

cell surface, lysosomes

protein sorting, secretory pathway: distribution of soluble and membrane proteins synthesized by the rough ER to final destinations at the _________ __________ (including secretion) or in ______________

rough endoplasmic reticulum, protein trafficking

two stages of secretory pathway protein sorting

cotranslational insertion

secretory pathway, rough ER (stage 1): step 1--synthesis of proteins bearing an ER signal/targeting sequence-- __________________ _____________ of newly made polypeptide chains into the ER membrane or across it into the ER lumen

cis golgi cisternae

secretory pathway, protein trafficking (stage 2): step 2--proteins packaged into transport vesicles that bud from the ER and fuse together to form a new ______-_________ ___________

ER

secretory pathway, protein trafficking (stage 2): step 3--ER enzymes or structural proteins--retained in the _________

ER

secretory pathway, protein trafficking (stage 2): step 3--ER enzymes or structural proteins--retrieved to the ER by vesicles that bud from the cis-golgi and fuse with the _________

nonvesicular cisternal maturation

secretory pathway, protein trafficking (stage 2): step 4--each cis-Golgi cisterna and contents moves from the cis to the trans face of the Golgi complex by ________________ _____________ _______________

retrograde transport

secretory pathway, protein trafficking (stage 2): step 5--____________ ____________ vesicles move Golgi-resident proteins to the previous Golgi compartment

plasma membrane

secretory pathway, protein trafficking (stage 2): step 6--constitutive secretion (all cells) - transport vesicles move continuously and fuse with the ___________ ______________

soluble

secretory pathway, protein trafficking (stage 2): step 6--constitutive secretion (all cells) - transport vesicles move continuously and fuse with the plasma membrane--___________ proteins are continuously secreted

membrane proteins

secretory pathway, protein trafficking (stage 2): step 6--constitutive secretion (all cells) - transport vesicles move continuously and fuse with the plasma membrane--____________ _____________ become plasma membrane proteins

regulated secretion

secretory pathway, protein trafficking (stage 2): step 7--___________ _______________--certain cell types

secretory vesicles

secretory pathway, protein trafficking (stage 2): step 7--regulated secretion (certain cell types)--proteins accumulated and stored in regulated _____________ ______________

neuronal, hormonal

secretory pathway, protein trafficking (stage 2): step 7--regulated secretion (certain cell types)--vesicles fuse with plasma membrane and secrete proteins only when cell receives a _______________ or _________________ signal secretion signal

endosome, lysosome

secretory pathway, protein trafficking (stage 2): step 8--lysosome-destined membrane and soluble proteins transported in vesicles that bud from the trans-golgi and fuse with the late ________________ for delivery to a ______________

soluble extracellular

protein sorting, endocytic pathway: step 9--vesicles budding from the plasma membrane take up __________ _________________ proteins and deliver them to lysosomes via late endosomes

protein transport

three types of coated vesicles mediate ____________ _______________ through different pathways

small GTPase

________ ___________ proteins direct coat protein polymerization on donor membranes to pinch off vesicles carrying different cargoes

coat shedding

___________ ______________ exposes Rab and SNARE proteins that target vesicles for fusion with specific target membranes

budding, fusion

overview of vesicle ____________ and _____________ with a target membrane

membrane

vesicles: bud from the donor ___________

fuse

vesicles: _______ with specific target membrane

protein coat

vesicles: assembly of a ___________ ________ drives vesicle formation and selection of specific cargo molecules

donor

vesicle budding from _________ membrane

GTP binding

vesicle budding from donor membrane: recruitment of _______-__________ G proteins to a region of donor membrane

cytosolic coat

vesicle budding from donor membrane: ___________ ________ protein complexes bind to the cytosolic domain of membrane cargo proteins

coat binding

vesicle budding from donor membrane: _________ _____________ evaginates the membrane - typical transport vesicle; ~50 nm in diameter

cargo, receptors

vesicle budding from donor membrane: some _________ proteins act as _____________to bind soluble proteins in the lumen and capture them into the budding vesicle

SNARE

vesicle budding from donor membrane: donor membrane-specific ___________ proteins (vesicle-SNARES; v-SNARES) captured in budding vesicle membrane.

coated vesicle

vesicle budding from donor membrane: donor membrane fusion - pinches off ____________ ____________

uncoated

vesicle budding from donor membrane: coated vesicle ____________ in cytosol - uncovers projecting v-SNARES for fusion targeting

coated vesicle budding

uncoated vesicle fusion

targeting

vesicle fusion with target membrane: ___________ -- interaction of specific v-SNARE with specific target membrane t-SNARES

fusion

vesicle fusion with target membrane: ___________ process

ER, cis golgi

transport step method, COPII: _______ to _______-____________

cis golgi, ER, golgi cisternae

transport step method, COPI: ______-__________ to ________ Later to earlier __________ ___________

COPII

coat proteins: Sec23/Sec24 and Sec13/Sec31 complexes, Sec16

Sar1

associated GTPase, OPII: __________

coatomers

coat proteins, OPI: ___________ containing seven different COP subunits

ARF

associated GTPase, OPI: __________

COPII, COPI

coated vesicles involved in protein trafficking

three, reversible polymerization

_________ major types of transport-specific coated vesicles--each with different type of protein coat formed by _____________ ___________ of a distinct set of coat and G protein subunits

GTPase

a conserved set of monomeric __________ switch proteins controls the assembly of different vesicle coats

trans golgi

vesicle-mediated protein trafficking from the _______-__________ network

sorting

trans-golgi network: distal ____________ compartment

sorts

trans-golgi network: _________ proteins into five different types of vesicles for transport to the plasma membrane, endosomes, and lysosomes

five

how many different types of vesicles does the trans-golgi network sort into for transport?

COPI vesices

five destinations trans-golgi complex sorts into for transport: retrograde transport of golgi enzymes to the trans-golgi (cisternal progression process)

AP complex vesicles

five destinations trans-golgi complex sorts into for transport: may have clathrin coat, transport lysosomal enzymes directly to lysosomes

constitutive secretory vesicles

five destinations trans-golgi complex sorts into for transport: unknown coat, transport constitutively secreted proteins and plasma membrane proteins to the plasma membrane

constitutive secretory vesicles

five destinations trans-golgi complex sorts into for transport: unknown coat, cargo proteins include ECM proteins, blood proteins, immunoglobulins

clathrin coated vesicles

five destinations trans-golgi complex sorts into for transport: (+AP2) transport lysosomal enzymes to late endosomes for eventual delivery to lysosomes

regulated secretory vesicles

five destinations trans-golgi complex sorts into for transport: unknown coat, store and process secreted proteins until signaled to fuse with the plasma membrane to secrete the proteins

ECM proteins, blood proteins, immunoglobulins

cargo proteins of constitutive secretory vesicles

regulated secretory vesicles

five destinations trans-golgi complex sorts into for transport: unknown coat, cargo proteins include digestive enzymes and peptide hormones

digestive enzymes, peptide hormones

what cargo proteins are included in the regulated secretory vesicles