peroxisomes

Question 1

what is the main function of peroxisomes?

Answer 1

beta fatty acid oxidation

Question 2

what happens in zellweger syndrome?

Answer 2

lack of or low no of peroxisomes, enzymes mislocalised to the cytosol instead of peroxisomes

Question 3

how many different complementation groups?

Answer 3

14

Question 4

which group has milder symtoms

Answer 4

A

Question 5

class 1 biogenesis mutants

Answer 5

affect matrix protein import

Question 6

class 2 biogenesis mutants

Answer 6

affects membrane biogenesis so no peroxisomes

Question 7

class3 biogenesis mutants

Answer 7

shape no. and distribution effected, miler symptoms

Question 8

what is PTS1

Answer 8

peroxisome targetting sequence, on c ter of peroxisome enzymes

Question 9

what two proteins form a pore in the membrane for peroxisome enzyme import?

Answer 9

pex5 and 14

Question 10

what complex is responsible for the extraction of ubiquitinated pex5 from the membrane?

Answer 10

pex15,1,6 ATPase complex

Question 11

steps of pulse chase experiment

Answer 11

GFP-PTS1 marker just after GAL1 promoter. switch on GAL promoter by growing on galactose for 3 hours then chase on glucose for 2 hours

Question 12

how do peroxisomes form?

Answer 12

by fission or can form de novo in mutants

Question 13

where are pex3 restricted to in pex19 deletion mutants

Answer 13

ER

Question 14

assay for de novo peroxisome formation

Answer 14

constitutively express HcRed-PTS1 marker, induce GAL-GFP-PTS1 by pulsing on galactose for 3hours. then stop expression and chase. red peroxisomes de novo. oranage are formed from new and preexisting peroxisomes

Question 15

what are dmn1 and vps1 required for?

Answer 15

normal peroxisome number

Question 16

what other proteins are required for peroxisome fission?

Answer 16

fis1, caf4, mdv1, dmn1

Question 17

mating assay for fission

Answer 17

label vps1/dmn1 double knockouts with GFP-PTS1, galactose pulse for 3 hours, chase on glucose 2 hours, mate with pex3 deletions to recover cells. vps1 recovers the cells

Question 18

what organelle provides peroxisomes with essential membrane consituients?

Answer 18

ER

Question 19

what mechanisms need to be switched on for peroxisome proliferation?

Answer 19

beta-oxidation enzymes and genes required for peroxisome biogenesis- ORE

Question 20

what does olate activate?

Answer 20

oaf1p

Question 21

what does oaf1p bind to

Answer 21

pip2p

Question 22

what does binding of hetrodimer to oelate response element do?

Answer 22

causes peroxisome biogenesis and postive feedback to activate more pip2

Question 23

what is required for peroxisome transport to bud?

Answer 23

actin cytoskeleton and myo2 and inp2

Question 24

what does inp1 do

Answer 24

anchors peroxisomes to periphery of mother cell and captures newly arrived peroxisomes in the bud

Question 25

what protein does inp1 interact with

Answer 25

pex3

Question 26

inp3 is required for what processes?

Answer 26

peroxisome and vacuole inheritence

Question 27

what protein is inp3 partially redundant with?

Answer 27

frk1