Lecture 2 - CAMs and Junctional Complexes

Question 1

Which cell adhesion molecule is associated with occludens and desmosomes (macula adherens)?

Answer 1

Cadherins

Question 2

Which molecular complex primarily serves to prevent paracellular transport?

Answer 2

Zonula occludens

Question 3

Which molecular complex is ONLY associated with the basal domains?

Answer 3

Hemidesmosomes

Question 4

Which CAMs are Calcium dependent?

Answer 4

Cadherins and Selectins

Question 5

Which CAMs are Calcium independent?

Answer 5

Integrins and Immunuglobulin superfamily molecules

Question 6

Which CAM recognizes carbohydrates?

Answer 6

Selectins

Question 7

Desmocollins and desmogleins (located in intercellular spaces) belong to which CAM?

Answer 7

Cadherins

Question 8

Which CAM recognizes extracellular matrix molecules, such as fibronectin and laminin, as a Ligand?

Answer 8

Integrins

Question 9

Which CAM recognizes Integrins as a Ligand?

Answer 9

Ig Superfamily

Question 10

Hemidesmosomes belong to which CAM?

Answer 10

Integrins

Question 11

State where each of the following Cadherins are found:

E-cadherins, N-cadherins, P-cadherins

Answer 11

Epithelial tissues, nerve cells, placenta

Question 12

Which protein serves as a major interface between the cadherins that hold adjacent cells together and their actin cytoskeletons?

Answer 12

Catenins

Question 13

State where each of the following Selectins are found:

L-selectin, E-selectin, P-selectin

Answer 13

Lymphocytes, Endothelial cells, platelets.

Question 14

Which molecular complex anchors cells together and reinforces the physical integrity of tissues and the cells that make up the tissues?

Answer 14

Zonula adherens

Question 15

Talin, Vinculin, and alpha-actinin are used as connecting proteins with which CAM?

Answer 15

Integrins

Question 16

What is a tonofilament? Give one example.

Answer 16

Proteins that generate or resist tension. Example: Keratin.

Question 17

N-CAM, ICAM-1 and ICAM-2 are members of which CAM?

Answer 17

Immunoglobulin superfamily.

Question 18

Which junctional complex anchor cells together and reinforce the physical integrity of tissues and cells that make up the tissues?

Answer 18

Adherens. “adhere” - hold cells together

Question 19

Which junctional complex establishes an impermeable barrier between adjacent cells, especially epithelial cells, that prevents paracellular transport and maintains concentration differences between the environments?

Answer 19

Occludens. “occlude” - keep stuff out

Question 20

Which junctions are composed of molecular pores that enable cells to rapidly exchange ions and small molecules that help coordinate activities among the cells?

Answer 20

Gap junctions.

Question 21

Which junctional complex travels all the way around the circumference of the cell and link all neighboring cells to the central cell? (belt-like complexes)

Answer 21

Zonula, can be either adherins or occludens. Zonula associate with intracellular actin microfilaments.

Question 22

Which junctional complex is a “spot” or snap-like junction and associate with intracellular intermediate filaments (tonofilaments)?

Answer 22

Macula. They are of the adherens variety. Referred to as desmosomes when associated with the lateral domains and hemidesmosomes when associated with the basal domain.

Question 23

What is type of plaques are desmogleins and desmocollins anchored to?

Answer 23

Desmoplakin and Plakoglobin.

Question 24

What proteins are associated with the junctional complex and are responsible for the occlusive properties of the tight junction?

Answer 24

Claudins and Occludins

Question 25

What are Unique components of the junctions:

Answer 25

finish later

Question 26

What are common components of the junctions:

Answer 26

finish later

Question 27

How many connexins are used to form one connexon and which junctional complex are they apart of?

Answer 27

6, Gap junctions