EV2

Question 1

syndecans

Answer 1

TM coreceptor proteoglycans such as G-coupled receptors

Question 1

ESCRT-dependent cargo loading

Answer 1

1. ESCRT-0 binds ubiquitinated cargo, PtdIn3P, Cathrin
2. ESCRT-1 binds ESCRT-II
   3) recruits ESCRTIII monomers (Vps20, 2, 24, Snf7)
   4) ESCRT-II engages cargo + 2x Vps20
   5) 2Snf7 filament spirals extend around the cargo
   6) ESCRT-III forms 65nm cargo-sequestering ring defining ILV membrane
   7) Snf7 assembly recruits DUBs
   8) Vsp24 and 2 co-assemble, resulting in ESCRT-III membrane sculpting helix invagination

Question 2

syntenins

Answer 2

• structural proteins

Question 3

Syndecan-Syntenin-ALIX pathway

Answer 3

• syntenin PDZ-domain binds to cytoplasmic syndecan and CD63
• LYPXL binds ALIX
• ALIX recruits ESCRT-III and Vps4
• induces ILV formation

Question 4

TETs

Answer 4

• can form TET-enriched micro domains
• can have partner protein (receptors, signals and cytosolic adaptors) via large extracellular loop

Question 5

LEL

Answer 5

cysteine motif, highly conserved

Question 6

Ceramide

Answer 6

conical head group induces induces negative membrane curvature which leads to invagination via lipid raft micro domains

Question 7

nSM2

Answer 7

hydrolyse SM phosphocholine moiety

Question 8

lipid raft microdomains

Answer 8

formed w flotillins and TET

Question 9

Evidence for the ceramide pathway: Oli-neu mouse lines

Answer 9

• oligodendroglial cells secrete proteolipid proteins enriched with ceramide lipids
• reduced with nSm2 RNAi and chemical inhibition

Question 10

Microvesicle biogenesis

Answer 10

1) membrane cargo clustering via TETs, lipid rafts and ESCRTs
2) lipid translocation and cytoplasmic cargo sorting via RBP
3) budding requires actin, ESCRT-III, calcium ions and ARF6
4) release: lipid flipping of ceramide membrane

Question 11

Exosome intracellular targeting

Answer 11

1) transported to PM by microtubule motors, Rab27b and small GTPases
2) tethering by Rab27a and Rab35
3) fusion via v and t SNAREs to soluble NSF attachment receptor proteins

Question 12

Syndecan-Syntenin-ALIX for intracellular targeting

Answer 12

1) Rab5 + EEs form MVB pathway gate
2) ALIX recruits ESCRT-III
3) Rab27a: exosome release

Question 13

Exosomes and APCs

Answer 13

• antigens bind to TCRs, promoting MHC release

Question 14

Exosomes and morphogens

Answer 14

Wnt can bind frizzled

Question 15

Cathrin/Calveolin/lipid-raft mediated endocytosis

Answer 15

1) exogenous EVs are taken into endogenous ILVs via back fusion
2) released cargoes are targeted to the lysosome for degradation, or to the nucleus for transcriptional modification

Question 16

prostasomes

Answer 16

1) transfer CD38 ADPR-cyclase to sperm
2) induces cyclic ADP ribose calcium ion mobilising messenger
3) increases sperm motility and fertilisation (in mice)

Question 17

prognostic biomarker

Answer 17

CD142 is a platelet tissue factor and coagulation initiator, as well as the most expressed EV surface marker for coronavirus

Question 18

TET8/9 exosome-like EVs

Answer 18

• tet8tet9 arabidopsis mutants show compromised EV production
• contain sRNAs that suppress fungal virulence

Question 19

PEN1

Answer 19

• defence-related proteins
• 10-17nt tinyRNAs