Extracellular Matrix

Question 1

Glucosaminoglycans (GAGs) are composed of ______.

Answer 1

a repeating disaccharide of glucuronic acid and N-acetylglucosamine

Question 2

List three types of cell movement made possible by GAGs.

Answer 2

1) Leukocyte rolling
2) Firm adhesion
3) Spreading

Question 3

Other than cells and water, what do GAGs bind?

Answer 3

Chemoattractants–to maintain gradients.

Question 4

Collagen binds to cells via ______ and ______.

Answer 4

fibronectin; laminin

Question 5

Cells bind to fibronectin and laminin along their ______ sequences.

Answer 5

RGD

Question 6

Cells degrade the ECM by releasing ______.

Answer 6

matrix metalloproteases (MMPs)

Question 7

What proteins connect actin to collagen?

Answer 7

Integrins (in the ECM) and actinin/talin/filamin (cytosol)

Question 8

How many subunits does integrin comprise?

Answer 8

Two: alpha and beta

Question 9

Which integrin subunit binds to actinin, filamin, and talin?

Answer 9

Beta

Question 10

Which molecule binds on the extracellular side in adherens junctions?

Answer 10

E-cadherin

Question 11

______ binds to E-cadherin in the cytosol.

Answer 11

Beta-catenin