2.12 extracellular matrix. Wound healing Flashcards
Epithelial tissue cells are connected by what?
cell to cell junction and have a limited ECM
What is the ECM?
the basal lamina/basement membrane
Where are the epithelial tissue cells?
outer layer, like the skin (epidermis) or lining of gut
Connective tissue cells are connect by what?
Through extensive ECM and few cell to cell junctions
Pertaining to Connective tissue cells, the fibroblasts secrete what?
the ECM
Where are Connective tissue cells usually located?
Internal structures like bone and tendon
What 2 roles does the ECM do?
Maintain tissue shape/structure, transmit signals.
What are integrins?
Anchor the ECM to the cell membrane and interact with the cells cytoskeleton
What do hemidesmosomes do?
Anchors intermediate filaments in a cell to extracellular matrix
What do actin linked cell matrix junctions do?
Anchors actin filaments in cell to extracellular matrix.
What are laminins?
Stay near the cell membrane and help cells stick together
What is essentially the ECM?
A lattice of collagen fibers
What is the structure of a collagen?
a triple helix = fibril (I, II. II)
What collagen forms sheets?
IV
What collagen cross the cell membrane?
XVII
What collagen is the protein part of proteoglycans?
XVIII
What collagen is associated with fibrils?
IX, XII
What collagen make up mpre than 90% in the skin?
I, III
What collagens are associated with Ethlers Danlos syndrome?
I, V.
What are the clinical representation of Ethlers Danlos syndrome?
Extra flexibility.
What collagen is associated with Alport Syndrome?
IV
What is the clinical presentation of Alport syndrome?
Kidney failure, and hearing loss.
What are proteoglycans?
Sugar modified peptides. Have more sugar than protein. They are huge.
What are the 4 types of proteoglycans?
Decorin, Versican, Aggrecan, Syndecans
What does Decorin do?
interacts with and regulated collagen fibers
What does Versican do?
Interacts with elastins and influences cell migration
Where are aggrecan found?
In cartilage
What are syndecans? What do they interact with?
Transmembrane proteins that interact with actin
What is a hyaluronan?
Sugar part of the proteoglycan.
What are elastins?
flexible, interweaves with the collagen fibers in teh ECM. Crosslinked at lysine residues.
What do fibronectins do?
Scaffold other ECM components together
What is one weird thing about elastins?
Not glycosylated
What are fibronectins?
More sugar with some protein.
What is important for wound healing?
Scaffolding function in fibronectins
What are MMPs important for?
Remodeling. Wounds.
True or False? MMPs are turned off during would healing.
true
What wounds do not leave scar tissue?
Fetal and oral wounds
