Lecture 6 Flashcards
What is the ECM? What does it do? Where is it?
The Extracellular Matrix. It exists at basal side of epithelial layers. It maintains cell attachments across long distances, allows communication, maintains tissue integrity and stores growth factors.
What is the ECM made of?
Integrins, collagen, fibronectin, and glycoproteins
What is an integrin?
They are integral membrane proteins that link the ECM to the Cytoskeleton
What is collagen?
Long protein that acts to link cells
What is fibronectin?
Links collagen to integrins
What are glycoproteins?
They are proteins that are covalently linked with sugar, they hydrate the ECM
What are epithelial layers?
The cell layer between body and environment
What is the layout of the ECM?
Integrins are inside the membrane of the epithelial layer and attach to fibronectins which then connect to collagen
What is a desmosome? Where are they located?
Distribute stretching force across tissue and connects the intermediate filaments (cytoskeleton) of adjacent cells. They are mostly in the middle
What is a gap junction? Where is it located?
They provide nonselective transport of small molecules between adjacent cells, they are large channels that that allow sharing of nutrients and signals between cells. They are the most basal junction.
What is a tight junction? Where is it located?
They function as rivets to seal cells together and prevent passage of molecules between cells from the environment into the body or vice versa. It is the most apical junction.
