Cell Adhesion

Question 1

What is the complex network of proteins and polysaccharide that cells secrete to anchor one another together called?

Answer 1

extracellular matrix

Question 2

What are the anchoring sites for actin filaments in adjacent cells called?

Answer 2

adherens junctions (connects actin filament bundle in ine cell to those in the next cell)

Question 3

What are the anchoring sites for intermediate filaments in adjacent cells called?

Answer 3

desmosomes (connects intermediary filaments in one cell to those in the next cell)

Question 4

Which anchoring junctions link actin filaments from the cytoskeleton of epithelial cells to the basal lamina?

Answer 4

Actin-linked-matrix junctions

Question 5

Which anchoring junctions link intermediary filaments from the cytoskeleton of epithelial cells to the basal lamina?

Answer 5

hemidesmosomes

Question 6

Which junction allows the transfer of water soluble molecules from cell to cell and link their cytoplasms?

Answer 6

gap junction

Question 7

Which junctions hold cells tightly together at the apex?

Answer 7

tight junctions

Question 8

Proteins of which superfamily chiefly mediate cell to cell attachment?

Answer 8

cadherins

Question 9

Proteins of which superfamily chiefly mediate cells to matrix attachment?

Answer 9

integrins

Question 10

What type of interactions fo cadherins usually prefer

Answer 10

homophilic (like to like)

Question 11

Which type of caherin is found in epithelial cells

Answer 11

E-cadherin

Question 12

Which type of caherin is found in neurons, heart, skeletal muscle, lens and fibroblasts?

Answer 12

N-cadherin

Question 13

Which type of caherin is found in breast epithelium, epidermis and placenta

Answer 13

P-cadherin

Question 14

Which type of caherin is found in endothelial cells

Answer 14

VE-cadherin

Question 15

The intracellular domains of classical cadherins are linked to actin filaments by which protein

Answer 15

β-catenin

Question 16

Which protein regulates the assembly of cadherin junctions

Answer 16

p120-catenin

Question 17

Plakoglobin (γ-catenin), vinculin and α-actinin are examples of what type of protein

Answer 17

other anchor proteins at the adherins junction

Question 18

What is the name of a characteristic, repetitive amino acid sequence of about 40 residues in length that is found in many proteins.

Answer 18

armadillo repeat

Question 19

Which ion regulates cadherin conformation?

Answer 19

Ca2+

Question 20

The absence of Ca2+ in cadherins results in what changes to its shape/integrity?

Answer 20

it contains less Ca2+ at its ‘hinges’ and so becomes floppy resulting in adhesion failures

Question 21

What is the homeostatic range for Ca2+ in extracellular fluid?

Answer 21

1.1 -1.4 mM Ca2+

Question 22

What has the many weakly linked cadherin junctions in cell to cell junctions been likened to?

Answer 22

Velcro

Question 23

What domains do cadherins bind to ?

Answer 23

N-terminal head regions