extracellular matrix and cell adhesion Hardy

Question 1

5 classes of ECM macromolecules

Answer 1

collagens
elastin
proteoglycans
hyaluronan
adhesive glycoproteins

Question 2

extracellular matrix of connective tissue

Answer 2

fibers (collagen, reticular)
proteoglycans
GAGs

Question 3

most abundant protein in human body

Answer 3

collagen

Question 4

which collagen ; 50% of all basal lamina protein

Answer 4

type 4

Question 5

what other collagen is part of basal lamina

Answer 5

type 7 (VII), 15 (XV), 18(XVIII)

Question 6

which type of collagen is primary protein of cartilage

Answer 6

type 2

Question 7

which type of collagen is primary protein of bone?

Answer 7

type 1

Question 8

which types form long fibrils(tendons, organ capsules, dermis)

Answer 8

1,2,3,5,11

Question 9

which type associated with fibril ( link collagen fibrils together)

Answer 9

9, 12, 14

Question 10

this type form anchoring fibrils (bind basal lamina to reticular fibers)

Answer 10

7

Question 11

this type form networks (basal lamina)

Answer 11

4

Question 12

collagen into triple helix, repeating amino acid sequence

Answer 12

Glycine - X - Y
X=proline
y=hydroxyproline

Question 13

most abundant type of connective tissue fibers

Answer 13

collagen fibers

Question 14

what is absent in scurvy

Answer 14

absence of collagen synthesis

hydroxylases that hydroxylate proline/lysine

Question 15

mutations that significantly decrease synthesis of pro-collagen chains

Answer 15

Osteogenesis imperfecta type 1

Question 16

most common cause of OI

Answer 16

Heteroxygous mutations of pro a1 (COL1A1) or pro a2(COL1A2) gene

Question 17

mutations that result in structural abnormal pro a chains=compromised assembly, abnormal folding

Answer 17

OI type 2-4

Question 18

this - assembly into procollagen trimers

Answer 18

c-propeptide domain

Question 19

single base substitution disrupts glycine affects what?

Answer 19

helical domain

Question 20

bone mineral density decreased - result in fragile/brittle bones

Answer 20

osteopenia

Question 21

symptoms of OI

Answer 21

osteopenia, bright-blue sclera, grossly discolored,abnormal teeth, hearing loss

Question 22

mutations in collagen structural genes

Answer 22

Ehlers-Danlos syndrome

Question 23

what genes are mutated in Ehler-Danols syndrome?

Answer 23

COL1A1, COL1A2, COL5A1, COL5A2

Question 24

Symptoms of E-D syndrome

Answer 24

joint hypermobility
hyperextensible skin, valvelty in textures, easily scarred
1:5000 live births

Question 25

extensive network of extremely thin fibers (threadlike)

Answer 25

Reticular fibers

Question 26

what type of collagen is reticular fiber?

Answer 26

type 3

Question 27

where those reticular fibers located?

Answer 27

around parenchyma of various organs | abundant in hematopoietic organs( speen,lymph nodes, bone marrow)

Question 28

what type collagens assemble into sheets?

Answer 28

type 4 and 8

Question 29

which fiber located in adrenal cortex and lymph node?

Answer 29

Reticular fiber

Question 30

which fiber is found in mesentery, dermis and artery?

Answer 30

elastic fibers

Question 31

thinner than collagen fiber; branching pattern. | subject to bending or stretching

Answer 31

elastic fibers

Question 32

elastic fibers are composed of what?

Answer 32

fibrillin and elastin

Question 33

how elastic fiber assemble?

Answer 33

fibrillin-1 and fibrilin-2 self assemble after secretion into extracellular space

Question 34

elastic fiber assembly; lysines condensed into a ring and what covalently cross-links elastins?

Answer 34

desmosine

Question 35

elastic assembles between what?

Answer 35

microfibers of fibrillin

Question 36

what gene is (90%) dominantly mutated in marfan syndrome?

Answer 36

fibrillin-1 gene

Question 37

what is poorly formed in marfan syndrom

Answer 37

elastic fibers

Question 38

triad of features of marfan syndrome?

Answer 38

skeletal ; long bone ocular: shifted lens (thickened) cardiovascular: mitrial valve problem/aortic problem

Question 39

what is the most dangerous feature of marfan syndrome

Answer 39

weakness of elastic fibers in the aorta - >enlargement of the vessel (aneurysm) - ->rupture = fatal consequences

Question 40

protein + GAG (covalently)

Answer 40

proteoglycans

Question 41

proteoglycan has more protein or GAG?

Answer 41

GAG

Question 42

Structural component of ECM

Answer 42

Proteoglycans

Question 43

what do proteoglycans do?

Answer 43

resiliency to compression anchor cells to ECM Bind/sequester some signaling proteins (FGF)

Question 44

what forms cartilage?

Answer 44

aggrecan aggregates form cartilage

Question 45

what is GAG?

Answer 45

repeating disaccharide of hexosamine (glucosamine or galactosamine) and uronic acid (glucuronic or iduronic)

Question 46

GAG forms what?

Answer 46

linear polysaccharides

Question 47

distinct features of GAG

Answer 47

highly hydrophilic | highly viscous

Question 48

All gag except hyaluronic acid are?

Answer 48

covalently attached to proteins (proteoglycan) synthesized in golgi rich in sulfate 10-40kDa

Question 49

largest GAG | most ubiquitous GAG

Answer 49

Hyaluronic acid (hyaluronan)

Question 50

how Hyaluronic acid is synthesized?

Answer 50

it is synthesized into ECM by enzyme(hyaluronate synthase) that is located in plasma membrane

Question 51

large polypeptide protein in which monosaccharides are covalently attached

Answer 51

glycoprotein (multiadhesive)

Question 52

glycoprotein contains more protein or GAG?

Answer 52

Protein

Question 53

features of glycoprotein

Answer 53

specific molecular interaction simultaneously bind multiple different molecules 'modules" relaying function or specific binding

Question 54

what are the glycoprotein, "modules/domains"?

Answer 54

complement-like, cysteine-rich, EF-hand, EGF, fibronctin 1, fibronectin 2, fibronectin 3, fibrinogen, immunoglobulin, lectin

Question 55

prevalent examples of glycoprotein?

Answer 55

fibronectin, laminin, tenascin

Question 56

4 primary components of basal lamina?

Answer 56

collagens laminins entactin/nidogen proteoglycans

Question 57

5 functions of basal lamina

Answer 57

1. structural attachment 2. compartmentalization 3. tissue scaffolding ( regeneration) 4. signaling/regulation 5. filtration (bidirectional)

Question 58

glomerular basement ( thick basal lamina) are created by?

Answer 58

``` capillary endothelial cells podocytes, collagen type 4, proteoglycans glycoproteins ```

Question 59

hereditary glomerulonephritis?

Answer 59

alport syndrome

Question 60

what collagens are affected in alport syndrome?

Answer 60

collagen 4 (alpa 3, 4, 5 genes)

Question 61

cause/symptoms of alport syndrome

Answer 61

thin and split basement membranes in glomeruli | --> hematuria, proteinuria, progressive kidney failure

Question 62

anti-glomerular basement membrane disease - autoantibodies "autoimmune disease"

Answer 62

goodpasture's syndrome

Question 63

what type of collagens are affected by goodpasture's syndrome

Answer 63

collagen type 4 (alpha 3)

Question 64

4 adhesion family

Answer 64

1. cadherin family 2. immunoglobulin family 3. integrin family 4. selectin family