Cell Junctions

Question 1

What are the 7 main features of Tight Junctions?

Answer 1

• Occuldin & Claudin
• Afadin-Nectin complex
• JAMS
• ZO-1, ZO-2, ZO-3
• F-ACTIN
• Form circumferential gasket that controls the paracellular pathway of molecules
• Define Cell Polarity*

Question 2

What are the 4 main features of Zonula Adherens?

Answer 2

• “Belt Desosome”
• Consists of a Plaque
• Forms a “belt” around apical side of epithelial cells
• Associated with Actin

Question 3

What are the 4 main features of Macula Adherens?

Answer 3

• “Spot Desosome”
• No Afadin-Nectin
• No Catenin Complexes
• Use Intermediate Filaments to attach to plaque

Question 4

What are the 4 main features of Hemidesosomes?

Answer 4

• Link Basal-Domain to Basal-Lamina
• Have inner membrane plate that that TONOFILAMENTS attach to
• Outmembrane plate that Integrin a6b4 and laminin 5 to basal membrane
• Intermediate-Filaments associated with plaque

Question 5

What are the 4 main features of Gap Junctions?

Answer 5

• Are NOT anchoring junctions
• Are communicating junctions
• Connect adjacent cells
• Use Connexon