ECM and Cell to cell interaction

Question 1

what are extracellular matrices composed of?

Answer 1

are composed of tough fibrous structural proteins embedded in a gel-like polysaccharide material known as ground substance

Question 2

glycosaminoglycans, or GAGs,

Answer 2

are gel-forming (frequently sulfated) polysaccharides of the extracellular matrix that consist of repeating units of disaccharides. remember negative charge, which brings in water, highly sulphated.

Question 3

Matrix adhesion proteins

Answer 3

the final class of extracellular matrix constituents, are responsible for linking the components of the matrix to one another and to the surfaces of cells.

Question 4

Fibronectin

Answer 4

is the principal adhesion protein of connective tissues, where as laminin is the principal adhesion protein of the basal lamina

Question 5

laminin

Answer 5

the principle adhesion protein of the basal lamina.

Question 6

Integrins

Answer 6

are the major cell surface proteins (integral plasma membrane proteins) responsible for the attachment of cells to the extracellular matrix. provide linkage between cytoskeleton intracelluarly and extracellularly.

Question 7

Focal adhesions-

Answer 7

a type of cell-matrix junction that attaches a variety of cells, including fibroblasts, to the extracellular matrix.

• link to actin filaments of cytoskeleton
• very important in cell movement over surfaces

Question 8

Hemidesmosomes-

Answer 8

another type of cell-matrix junction, mediate epithelial cell attachments at which a specific integrin interacts with laminin in the basal lamina.

• link to intermediate filaments of cytoskeleton
• strongest cell-matrix junction

Question 9

adherens junction-

Answer 9

is a region of cell-cell adhesion at which the actin cytoskeleton is anchored to the plasma membrane.

Question 10

desmosome

Answer 10

is a region of adhesion between epithelial cells at which intermediate filaments are anchored to the plasma membrane.
- strongest cell-cell junction

Question 11

adheren junctions( cadherins)

Answer 11

link the actin cytoskeleton of adjacent cells via cell junctions