Extracellular Matrix

Question 1

Aggrecan

Answer 1

The major proteoglycan in cartilage between bones

Question 2

Aneurysm

Answer 2

Widening of artery due to weakness in vessel wall

Question 3

Angiogenesis

Answer 3

Formation of new blood vessels

Question 4

Basal lamina

Answer 4

Skin. Layer of ECM proteins and basement membrane secreted by epithelial cells

Question 5

Basement membrane

Answer 5

Layer of ECM and fibrous proteins anchoring and supporting the epithelium

Question 6

Epithelium

Answer 6

Outer layer

Question 7

Extracellular matrix

Answer 7

3D network of proteins and carbs surrounding cells

Question 8

Glomerulus

Answer 8

Cluster of capillaries in kidney that filter waste. Initiate urine formation

Question 9

Glycosaminoglycan

Answer 9

Long chain of disaccharides where residues are sulfated, making it highly (-) charged

Question 10

Periosteum

Answer 10

Dense fibrous membrane covering bones except at joints

Question 11

Fibril Forming Collagens

Answer 11

Collagens I and III

Question 12

Network Forming Collagens

Answer 12

Collagen IV

Question 13

Anchoring fibril collagens

Answer 13

Collagen VII

Question 14

Collagen I

Answer 14

Fibril forming. Connective tissue of skin, bone, tendon, cartilage, and ligaments. Surround Cornea and organs. Perpendicular

Question 15

Collagen IV

Answer 15

Network forming. Flexible, sheet like mesh bc of BREAKS in triple helix structure.
Filtration in glomerulus

Question 16

Collagen Type VII

Answer 16

Anchoring fibrils, keeps basement membrane intact.
Epidermis-dermis junction in skin
DEB affects these

Question 17

Osteogenesis imperfecta

Answer 17

Weak bones.
Affects type I collagen.
Gly to serine, doesn’t correctly fold

Question 18

Alpert syndrome

Answer 18

Affects type IV collagen.

Nephritis, hearing loss, and ocular lesions

Question 19

Dystrophic Epidermolysis Bullosa (DEB)

Answer 19

Skin easily blisters.
Affects type VII collagen.
Cleavage site AT DERMIS

Question 20

Proteoglycans

Answer 20

• Heterogenous. Mostly sugar, some protein.
• Regulate signaling molecules
• fibroblast growth factor (fgf) must bind yo activate its receptor
• filtering apparatus in kidneys
• aggrecan

Question 21

Heparanse

Answer 21

Clips proteoglycan to allow growth factor to bind to blood vessel, allowing tumor growth

Question 22

Fibrillin

Answer 22

Form micro fibers and associate w elastic fibers in ECM.
Found in skin, eye lens, aorta, periosteum
Provides scaffold

Question 23

Marfan Syndrome

Answer 23

Gene mutation of fibrillin 1.
Long limbs, nearsighted (lens dislocation), and large heart (aneurysm)
-Growth factor stays active

Question 24

Fibronectin

Answer 24

2 large subunits connected at carboxyl terminal by disulfide bonds.

• multiple forms from one gene that is alt. RNA spliced
• inflammatory phase blood clotting, wound healing.
• low levels = premature deliveries

Question 25

Laminin

Answer 25

3 chains form cross shaped structure

Question 26

Junctional Epidermolysis Bullosa

Answer 26

Defect in laminin 5 (a3, B3, y2 chain) between dermis and epidermis

Question 27

MMPs (Matrix Metalloproteinases)

Answer 27

ECM degradation enzymes.
Require Zn or Ca
-facilitate release of cells that migrate into wound in inflammatory phase

Question 28

Fibroblasts

Answer 28

Synthesize collagen, fibronectin in proliferative phase

Question 29

Remodeling phase

Answer 29

Collagen 3 replaced by collagen 1

Can takes weeks to months