Antibacterial autophagy

Question 1

What does cell autonomous innate immunity refer to?

Answer 1

that all nucleated cells can protect themselves from pathogenic invasion

Question 2

What are the options intracellularly for pathogens to live?

Answer 2

vesicles or cytosol

Question 3

What do extracellluar pathogens face in terms of immunity?

Answer 3

antibodies; complement; phagocytes

Question 4

What do vesicular pathogens face interms of immunity?

Answer 4

low pH; hydrolytic enzymes; radicals

Question 5

What do cytosolic pathogens face in terms of immunity?

Answer 5

autophagy; inflammasome; host clel death

Question 6

Give examples of pathogens that live in the cytosol?

Answer 6

shigella; listeria

Question 7

What is autopahggy?

Answer 7

enclosure of cytoplasmic constituents in a double membrane vesicle- autophagosome

Question 8

What proteins are required for autophagy?

Answer 8

ATG proteins

Question 9

Which ATG proteins are particularly important for autophagy?

Answer 9

ATG8/LC3

Question 10

What name is given to bacterial autophagy?

Answer 10

xenophagy

Question 11

What fuses with autophagosome?

Answer 11

late endosomes or lysosomes

Question 12

What are the 3 general stages in xenophagy?

Answer 12

intial danger signal; cargo labelling; label decoding

Question 13

What protein is used for cargo labelling?

Answer 13

ubiquitin

Question 14

What is used for label decoding?

Answer 14

autophagy adaptor/receptor

Question 15

What is hte function of autophagy receptors?

Answer 15

decode “eat me” signals and drags intracellular microbes into autophagosomes

Question 16

What are the 3 domains found on autophagy receptors?

Answer 16

one for interaction ot immune signalling; LIR domain and one which recognises an eat me signal

Question 17

What is the LIR region for?

Answer 17

LC3 interacting region which ensures targeting of the autophagy receptor to LC3 anchored in the phagosome membrane

Question 18

Give examples of autophagy receptors?

Answer 18

NDP52; optineurin; T6BP

Question 19

What happens when NDP52 is missing?

Answer 19

rampant intracellular bacteria

Question 20

Which types of cell is ubiquitin foudn in?

Answer 20

eukaryotic cells

Question 21

By what type of bonding does ubiquitin modify other proteins?

Answer 21

covalently

Question 22

How many enzymes does ubiquitin linkage require ?

Answer 22

3

Question 23

How are ubiquitin chains formed?

Answer 23

by lysine residues- the shape of the chain determiens the repsonse to the ubiquitin

Question 24

How does the cell recognise cytosolic bacteria?

Answer 24

bursting of the vacuole exposes host carbohydrates that aren’t normally present

Question 25

Which receptor is responsible for detecting cytosol exposed carbohydrates?

Answer 25

danger receptor- galectin-8

Question 26

What receptor is galectin-8 able to bind directly to?

Answer 26

NDP52

Question 27

What is macro-autophagy?

Answer 27

delivers cytoplasmic cargo to the lysosome through the autophagosome

Question 28

What is micro-autophagy?

Answer 28

cytosolic components are directly taken up by the lysosome through invagination of the lysosomal membrane

Question 29

What is chaperone-mediated autophagy?

Answer 29

targeted proteins are translocated across the lysosomal membrane in a complex with chaperone proteins that are recognised by a receptor LAMP-2A

Question 30

How does salmonella escape its salmonella containing vacuole?

Answer 30

type 3 secretion system

Question 31

What is a good marker for autophagy?

Answer 31

LC3