ECM proteins

Question 1

proteoglycan

Answer 1

aggregate of glycosaminoglycans

Question 2

GAGs

Answer 2

mucopolysaccharides, repeating disaccharide chins; net negative surface charge and repel each other

Question 3

Cartilage matrix lined with GAGs

Answer 3

produced slippery consistency due to GAGs and swelling pressure due to turgor (ECM resists compression)

Question 4

Collagen

Answer 4

tough protein fibers resistant to shearing forces

Question 5

Collagen molecule

Answer 5

3 alpha chains, with every 3rd aa being a GLYCINE allowing tight packing

Question 6

Banding pattern of collagen

Answer 6

due to packaging of collagen into fibrils

Question 7

Synthesis of collagen

Answer 7

RER, Hydroxylation of PROLINE and LYSINE (VIT C DEPENDENT) and Glycosylation of hydroxylysines

Question 8

Tropocollagen

Answer 8

within ECS, pro peptides are cleaved off off the collagen triple helix to yield tropocollagen, it will link to form mature collagen fibrils and cross-linked

Question 9

Scurvy

Answer 9

Vitamin C deficiency, hydroxylation does not occur, helix cannot form, less functional collagen for tissue strength - effects tissue with rapid turnover of collagen (blood vessels, tooth loss)

Question 10

Osteogenesis Imperfecta

Answer 10

inherited defect in collagen - all collagen; abnormal or decreased production of collagen Type I: mild, brittle bones; Type II: lethal

Question 11

Ehlers-Danlos

Answer 11

Defects in fibrillar collagen; joint hyperextension, stretchy skin

Question 12

Elastin

Answer 12

Gives tissues in ECM the ability to stretch and recoil

Question 13

Tropoelastin

Answer 13

newly synthezied elastin interacts with FIBRILLIN-1 which serves as a scaffold

Question 14

Marfan Syndrome

Answer 14

mutation in fibrillin-1, inability to maintain proper elastin structure (aorta, lens of eye, ligaments of eye most effected due to high abundance of elastin) long limbs, digits, tall, hyper mobility of joints and scoliosis

Question 15

antitrypsin deficiency

Answer 15

inappropriate destruction of lung elastin; cannot keep neutrophil elastase in check - emphysema

Question 16

Neutrophil elastase in normal lungs

Answer 16

destroys bacteria and infection in lungs, low amounts

Question 17

antitrypsin in healthy people

Answer 17

monitor the destructive action of the neutrophil elastase t prevent damage to lungs

Question 18

Adhesive proteins in ECM

Answer 18

fibronectin and laminin

Question 19

Fibronectin

Answer 19

in all CT, multifunctional (binds cells via adhesion molecule integrin bound to actin, collagen, and proteoglycans) to link cells to ECM

Question 20

Laminin

Answer 20

found in epithelial tissue, multifunctional (binds cells via adhesion molecule integrin bound to actin, collagen, and proteoglycans) to link cells to ECM

Question 21

Cell adhesion molecules

Answer 21

cadherins, selectins, immunoglobulin superfamily, integrins

Question 22

Cadherins

Answer 22

Ca-Dependent cell-cell adhesion (E-, P-, N-cadherin), transmembrane and join actin filaments to mediate interactions of cells. MAIN adhesion

Question 23

Selectins

Answer 23

cell surface carbohydrate-binding protein mediates cell-cell adhesion (SELECTIN—GLYCOPROTEIN/GLYCOLIPID) transient - bloodstream

Question 24

Members of immunoglobilin superfamily

Answer 24

Ca-independent cell-cell adhesion LIGANDS FOR INTEGRINS, CAM, transient expression during development (ICAM, VCAM)

Question 25

Integrins

Answer 25

alpha and beta transmembrane adhesion molecules cell-cell and cell-ECM adhesion; Tyoe 2 beta of leukocytes for binding to endothelial immunoglobulin (ICAM, VCAM)

Question 26

Cell Matrix Adhesion

Answer 26

Integrins, weak adhesion of cell to ECM; integrin binds to adaptor protein connected to intracellular actin changes in cell can result in alterations of ECM binding

Question 27

interruptions to cell-cell or cell-matric interactions

Answer 27

cancer, asthma, RA, disease