Extracellular Matrix Flashcards
What are the 5 types of molecules found within ECM?
Fibrins -Elastin, Collagen,
Ground Substances- Proteoglycans, Glycosaminoglycans (typically hyaluronan), Glycoproteins
How many types of collagen are there?
28
What are the structural components of collagen?
3 collagen polypeptides secreted into ECM form triple helix
Formed of triple amino acid repeat (Glycine -X -Y)
Where is collagen type 1 found?
Skin, in tendons, and ligaments, and bone, fibrocartilage
Where is collagen type 2 found?
Hyaline cartilage
Where is collagen type 3 found?
Found in tissue, liver, lymphoid organs, granulation tissue (i.e. reticulin)
Where is collagen type 4 found?
Basement membrane
Where is collagen type 5 found?
Linker to basement membrane, and associates with collagen 1 in cornea
What is the purpose of elastin?
Enables shape recovery following deformation,
What is another name for collagen 3?
Reticulin
How is elastin assembled
Fibrous, assembly relies on presence of glycoprotein fibrillin which gets incorporated into the elastin fibre.
Where is elastin found?
In tissue (lungs, bladder and blood vessels)
What staining would you use when looking for elastin or collagen?
Van Gieson Stain
It would stain dark pink/purple and help differentiate between smooth muscle and
What are proteoglycan functions?
Highly negatively charged, therefore attracts water.
This retention supplies resistance to forces and hydration
What are Glycosaminoglycans (GAGs)and what do they form?
Chains of repeating disaccharide units.
Form carbohydrate part of proteoglycans
What Glycosaminoglycans (GAGs) are used in forming cartilage?
Chondroitin Sulphate
Keratan Sulphate
What glycosaminoglycans (GAGs) form synovial fluid?
Hyaluronan (hyaluronic acid)- also found in other body tissues
Can bind 10,000 times its own weight.
What glycosaminoglycans (GAGs) form basement membrane?
Heparan Sulphate
What are proteoglycans?
Assembly of GAGs along a protein core (95% carbohydrate)
What is the location and the GAGs that form Aggrecan?
Cartilage
Keratan Sulphates
Chondroitin Sulphates
What is the location and the GAGs that form Perlecan?
Basement Membrane
Heparan Sulphate
What is the location and the GAGs that form Syndecan?
Cartilage
Chondroitin Sulphate
Heparan Sulphate
What is the location and the GAGs that form Decorin?
Widespread in connective tissue
Chondroitin Sulphate
Dermatan Sulphate
What are the components of Aggrecan and its primary role in the body?
Assemble along Hyaluronan Core to form large negatively charged aggregate
In cartilage and joints, it interacts strongly with Collagen T2, to help resist deformation