Test 2 Cell to Cell adhesion

Question 1

Homophilic interactions

Answer 1

Proteins binding to same proteins

Question 2

Heterophilic interactions

Answer 2

Proteins binding to different proteins.

Question 3

Where is E-selectin synthesized and where are the oligosaccharides it binds to?

Answer 3

Endothelial Cells WBCs

Question 4

Where is P-selectin synthesized and where are the oligosaccharides it binds to?

Answer 4

Platelets WBCs

Question 5

Where is L-selectin synthesized and where are the oligosaccharides it binds to?

Answer 5

WBC Endothelial Cells

Question 6

Role of selectins?

Answer 6

Mediate initial weak adhesion between WBC and endothelial cells.

Question 7

Role of Integrins?

Answer 7

Secure a tighter interaction between WBC and ICAMS on the endothelial cell.

Question 8

Where are integrins located?

Answer 8

WBC

Question 9

What is the model for Selectins and Integrins in a immune response?

Answer 9

WBC is in blood, Binds to selectin, Then binds tighter by integrins binding with ICAMS.

Question 10

What does ICAM stand for?

Answer 10

Intercellular adhesion molecules

Question 11

What is the activation of integrin called?

Answer 11

Inside-out signaling.

Question 12

Cadherin general info

Answer 12

Ca2+ dependent, homophilic signaling. Requires Catenin for adhesion

Question 13

Role of A-catenin

Answer 13

Links actin filament to b-catenin

Question 14

Role of B-catenin

Answer 14

Links cytoplasmic domain of cadherin to A-catenin. Can also go into the nucleus and bind to transcription factor (Tcf-4), which can then turn genes on.

Question 15

Role of P120

Answer 15

Binds to cytoplasmic domain of cadherin, and regulates stability of cadherin-actin link.

Question 16

Cadherin and cancer?

Answer 16

Cancer cells have no cadherins. E-cadherin activity is lost and so there is no attachment.

Question 17

Desmosomes bind to what?

Answer 17

Intermediate filaments.

Question 18

APC protein mutation causes what?

Answer 18

Familial adenomatous polyposis (FAP) Hundreds of thousands of polyps in the colon.

Question 19

Desmosome related disease?

Answer 19

Pemphigus Vulgaris - Blisters in mouth and skin.

Question 20

Hemidesmosomes complex

Answer 20

Bind IF to extracellular matrix. Contains Integrins: A6-B4

Extracellular matrix ⇒ Integrins ⇒ intermediate proteins ⇒ intermediate filaments ⇒ cell

Question 21

Cell - Cell Junctions

Answer 21

• Adherens junction
• Desmosome
• Tight junction
• Gap Junction

Question 22

Cell - matrix junctions

Answer 22

Focal adhesion and Hemidesmosome

Question 23

Linking proteins, Intracellular proteins, and cytoskeletal proteins for Adherens Junctions.

Answer 23

• Linking proteins:
  
  • Cadherin
  • Nectin
• Intracellular Proteins:
  
  • Catenins
  • P120
  • Afadin
• Cytoskeletal Proteins:
  
  • Actin

Question 24

Linking proteins, Intracellular proteins, and cytoskeletal proteins for Focal Adhesion

Answer 24

• Linking proteins:
  
  • Integrin
• Intracellular Proteins:
  
  • Talin
  • a-actinin
• Cytoskeletal Proteins:
  
  • Actin

Question 25

Linking proteins, and cytoskeletal proteins for Desmosomes

Answer 25

• Linking proteins:
  
  • Cadherin-like
• Cytoskeletal proteins:
  
  • Intermediate Filaments

Question 26

Linking proteins, and cytoskeletal proteins for Tight Junctions

Answer 26

• Linking Proteins:
  
  • Occludin
  • Claudin
  • JAMs
• Cytoskeletal Proteins:
  
  • Actin

Question 27

Linking proteins for Gap Junctions

Answer 27

• Linking proteins:
  
  • Connexon

Question 28

Linking proteins, and cytoskeletal proteins for Hemidesmosomes?

Answer 28

• Linking proteins
  
  • Integrin
• Cytoskeletal proteins
  
  • Intermediate filaments

Question 29

Role of tight junctions?

Answer 29

Prevent things from going between the cells.

Question 30

Connexon structure, throughput

Answer 30

Made up of 6 connexin, things with less than 1000 molecular weight.