Extracellular matrix Flashcards
T/F Laminins and fibronectins are found in soluble and insoluble forms.
True
What are tight junctions networks composed of
Thin fibrils where proteins remain embedded.
What is the major structural protein of the Extracellular matrix of animals
Collagen
What is the localization of GAP junctions
They project out from the plasma membrane of 2 neighboring cells.
T/F Mutations in laminins and fibronectins cause epidermolysis bullosa
False
What causes epidermolysis bullosa
Mutations in laminins and collagen
Despite the fact that they possess no intrinsic signaling ability, integrins are still considered signaling receptors. Why?
Development is in response too signals.
Bind to signaling proteins.
Tissue cells are connected to the extracellular matrixby receptors that bind to the adhesive protein ___?
Collagen
Where are both Laminins and fibronectins found?
In the extracellular matrix
What do both laminins and fibronectins bind to?
Collagen and integrins
What is the domain like of only Collagen, not laminin or fibronectin?
Collagen has a triple helical domain
What are GAP junctions?
Protein structures that directly transfer small molecules between two cells.
What are the three repeating amino acids that commonly exist in coiled collagen proteins.
Proline, hydroxyproline, and Glycine.
Where are laminins primarily found?
In the Basal Lamina
What connects cells in plants to equalize the ionic concentrations of their cytosol
Plasmodasta
Define extracellular matrix
The network between cells that is made by the cells.
What are the molecular connections making Gap Junctions
Connexons that are made up of 6 Connexins.
Where are hemidesmosomes found
on the basal surface of the cells
What do Hemidesmosomes do?
Connect the ECM to Intermediate fillaments
provides stability to the epithelial sheet.
Where are adherens found?
On the cell surface.
What do adherens contain?
transmembrane cadherin receptors.
Define Affinity modulation of integrin receptor binding
Variations in the binding strength of individual receptors
Define avidity modulation of integrin receptor binding.
Variation in the clustering of integrin receptors.
What are hemidesmosomes and what do they do?
A protein complex that provides stability to the epithelial sheet.
Connect the ECM to Intermediate fillaments
What is the structure of an integrin receptor
18 alpha subunits that bind to 8 beta subunits to make 24 combinations.
They bind to cytoskeleton and signaling proteins.
What is the function of integrin receptors?
Interact with adaptor proteins to create a signal for binding ECM to proteins.
What makes Elastin so elastic.
Covalent links between lysine side chains.
