lecture 10

Question 1

where does digestion of misfolded proteins occur

Answer 1

proteasome in the cytosol

Question 2

where do COPII vesicles travel

Answer 2

from ER to cis Golgi

Question 3

where do COPI vesicles travel

Answer 3

from the trans golgi back to ER
or from trans golgi back to cis golgi

Question 4

where do clathrin coated molecules travel

Answer 4

from the trans golgi to lysosomes or endosomes

Question 5

what does an early endosome do

Answer 5

it sorts and traffics new things brought in through endocytosis

Question 6

what is vesicle budding driven by

Answer 6

assembly of a protein coat

Question 7

what is adaptin in clathrin coated vesicle transport

Answer 7

that forms a bridge between plasma membrane and and clathrin by binding to the cargo receptor `

Question 8

what does dynamin do

Answer 8

wraps around plasma membrane, constricts and detaches clathrin coated vesicles

Question 9

what pathway are clathrin coated vesicles incloved in

Answer 9

both endocytic from the plasma membrane
and secretory pathway from the Golgi apparatus

Question 10

what are the 2 roles of adaptin listed

Answer 10

bind cargo receptors / select
bridge cargo and clathrin

Question 11

what moves vesicles towards specific target compartments

Answer 11

microtubules
motor proteins

Question 12

what does vesicle tethering depend on

Answer 12

rab proteins
tethering protein

Question 13

whats the movement of vesicles to their particular compartment (4)

Answer 13

move vesicles to compartment
tether vesicles to the target compartment
dock vesicles with target compartment
fusion between vesicle and target membrane

Question 14

what are the molecular markers in vesicle delivery

Answer 14

rab proteins
tethering proteins

Question 15

what kind of protein is a rab? what is it associated with

Answer 15

G protein

associated with a lipid in the membrane
lipid anchored

Question 16

if there is a GTP bound to rab, what can it do?

Answer 16

it can bind to a tethering protein

Question 17

what does tethering do?

Answer 17

brings the rab protein and tethering protein together

Question 18

are rab and tethering proteins specific

Answer 18

yes

Question 19

when GTP is bound to rab, what happens

Answer 19

it is active, it can bind with tethering protein

Question 20

what proteins does vesicle docking depend on

Answer 20

SNARE proteins

Question 21

what type of protein are snares

Answer 21

integral membrane proteins

Question 22

what does docking do

Answer 22

brings the 2 membranes close enough that they can fuse

Question 23

where are v snares located

Answer 23

vesicles

Question 24

where are t snares located

Answer 24

target (plasma membrane)

Question 25

in the neuron plasma membrane, how many t snares are there

Answer 25

2 but 3 in total because there are 2 SNAP 25 syntaxin SNAP 25 (2)

Question 26

in the synaptic vesicle membrane, how many v snares are there (neurons)

Answer 26

1 synaptobrevin

Question 27

does snap 25 have a transmembrane domain

Answer 27

no

Question 28

which snares have a transmembrane domain for neurons

Answer 28

syntaxin and synaptobrevin

Question 29

whats the conformation of the 4 stranded bundle created by the neuron proteins

Answer 29

a helices

Question 30

is the cytosolic surface of our vesicle maintained as fusion occurs?

Answer 30

yes

Question 31

does the lumen of our vesicle remain as fusion occurs?

Answer 31

no the lumen will become the extracellular side

Question 32

wha are the two types of endocytosis

Answer 32

bulk phase endocytosis (pinocytosis/anything that comes with fluid comes with fluid) receptor mediated endocytosis (specific / clathrin coated vesicles)

Question 33

what is phagocytosis

Answer 33

bringing in very big particles from extracellular environment ie a bacteria

Question 34

whats the main destination of endocytic pathway

Answer 34

lysosomes

Question 35

what kind of enzymes do you find in lysosomes

Answer 35

acid hydrolases

Question 36

whats the average ph in a lysosome

Answer 36

5.0 more acidic to carry out functions

Question 37

how is the pH in lysosomes maintained

Answer 37

by a protein pump in lysosome membrane that will pump in protons

Question 38

what is autophagy

Answer 38

recycling of old organelles

Question 39

where do phagosomes, autophagosomes and late endoscopes get degraded

Answer 39

`lysosomes

Question 40

what are peroxisomes for

Answer 40

they are enzymes that carry out metabolic reactions

Question 41

are proteins used by mitochondria, nucleus, chloroplasts, and peroxisomes moved co transitionally ?

Answer 41

nope they just get transported across their membranes once they are already synthesized

Question 42

which organelles do not require vesicles to deliver them their proteins ? (ie, the proteins they require are created on free ribosomes) (4)

Answer 42

nucleus mitochondra chloroplasts peroxisomes

Question 43

what does posttransational mean

Answer 43

when a protein is transported across a membrane after synthesis

Question 44

what are the 2 compartments of peroxisomes

Answer 44

boundary membrane internal matrix

Question 45

how do we get movement into peroxisomes

Answer 45

there's a specific targeting signal that is a PTS signal results in translocation

Question 46

where are TOM complexes found

Answer 46

the outer membrane of mitochondria

Question 47

where are TIM complexes found

Answer 47

the inner membrane of mitochondria

Question 48

what do TIM and TOM do

Answer 48

they act as receptors and recognizers but also channels for the polypeptide to go through

Question 49

when do polypeptides fold in regards to entering a mitochondria

Answer 49

a polypeptide will not fold until it enters the mitochondrial matrix

Question 50

whats the other name for the secretory pathway

Answer 50

biosynthetic pathway