Lecture 9

Question 1

what is the SEC pathway

Answer 1

ER - Golgi - PM/endosome/lysosome

Question 2

what genetic organisms are commonly used to study membrane trafficking

Answer 2

yeast
mice
zebrafish
C.elegans

Question 3

what are advantages of using yeast

Answer 3

easily controlled
entire genome known
cheap and easy to grow
limited gene diversity
fundamental pathways conserved

Question 4

what are disadvantages of yeast

Answer 4

limited cell-cell contact
small - high resolution imaging needed
cell wall

Question 5

how many genes were discovered in relation to SEC pathway

Answer 5

23
class A - accumulation in cytosol
class B - accumulation in RER
class C - accumulation in ER-Golgi vesicles
class D - accumulation in Golgi
class E - accumulation in secretory vesicles

Question 6

why werent all genes discovered

Answer 6

only identified temperature sensitive mutants
only did secretion to PM
any reduntantly functioning genes would not be identified

Question 7

why is endocytosis important

Answer 7

retrieval of molecules
down regulation if signals
remodelling cell surface

Question 8

how many genes were identified in VPS

Answer 8

> 60

CPY was followed as normally excreted - gycosylated and proteolytically cleaved at different stages so can be followed

Question 9

MVB

Answer 9

multi vesicular body