Extracellular Matrix Flashcards
Which core matrisome protein includes laminin and fibronectin?
A. Collagens
B. Glycoproteins
C. Proteoglycans
D. Elastin
B
Which core matrisome protein is linked to Marfan syndrome?
A. Collagens
B. Glycoproteins
C. Proteoglycans
D. Elastin
D
Which core matrisome protein includes aggrecan?
A. Collagens
B. Glycoproteins
C. Proteoglycans
D. Elastin
C
TGF-ß is classified as which type of matrisome associated protein?
A. ECM regulator - modifying enzyme
B. ECM regulator - protease
C. ECM-affiliated protein - enriched in ECM preparation
D. Secreted factor
D
Lysyl oxidases:
A. Function to covalently crosslink the ECM
B. Function to remove sulfate groups from sugars
C. Add phosphate groups
D. Remove phosphate groups
E. Remodel and degrade the ECM
A
Prolines:
A. provide a twist in the peptide chain to allow the helix to form
B. allow for close packing of the helix
C. both of these
D. none of these
A. Note - GLYCINES are responsible for close packing of the helix, since they have no side chains.
Collagen Type I is classified in which collagen family?
A. Forms cross-striated fibrils
B. Has interrupted triple helix
C. Network-forming
D. Transmembrane collagen
E. Serves signaling funcions as an inhibitor of angiogenesis
A
All of the following are true regarding Collagen I except:
A. It is a hetero-trimer of 2 alpha1 and 1 alpha2 chains
B. Is it non-immunogenic and has a short half life
C. Its trimer can be isolated by digesting all other proteins by pepsin
D. Fiber-associated collagen has an uninterrupted triple helix
E. Endothelial cells in collagen gels form tubes
F. There are more collagen genes than collagen types
B - Collagen IS in fact non-immunogenic, but has a LONG half life
The core matrisome protein that makes up the fibers (left) and the fibrils (right) in the image displayed has the following function:
A. resist tensile and shear stress in tissue
B. facilitate bone formation
C. aid cell attachment
D. regulate cell differentiation and shape
E. all of the above
E
The main function of collagen I is to resist tensile _________.
A. compression
B. stress
C. both of these
D. neither of these
B
A main function of proteoglycans is to resist tensile _________.
A. compression
B. stress
C. both of these
D. neither of these
A
Glycoproteins:
A. Can cause vascular wekaness and arterial dissections when mutated
B. Bind and store large quantities of water
C. Are responsible for cell adhesion and migration
D. Are highly glycosylated chains
E. All of these above
C
Your patient, a 27-year old female, exhibits bone fragility, skeletal deformity, marked short stature (94 cm tall), light sclerae, hearing loss and tooth fragility (dentinogenesis imperfecta). You conclude that she has:
A. Osteogenesis imperfecta Type I
B. Classic Ehlers-Danlos syndrome
C. Arthrochalasis Ehlers-Danlos syndrome
D. Osteogenesis imperfecta Type III
E. None of these
D - note that a patient with OI Type I would generally present with a taller stature.
Osteogenesis imperfecta:
A. Is a mostly autosomal recessive disease caused by mutations in enzymes important for collagen biosynthesis
B. Involves an abnormal triple helix that is secreted and forms collagen I fibrils
C. Is relatively common, with an incidence of 1/5000 people
D. Is commonly caused by a missence mutation that replaces a glycine with a bulky amino acid
D - OI is generally autosomal dominant and involves a mutation in COL1A1 or COL1A2
Your patient presents with skin hyperextensibility and joint hypermobility, easy bruising, abnormal, and “cigarette paper” scarring. Upon obtaining a PMH, you find a history of recurrent dislocations, contractures, scoliosis, and fractures. What is your diagnosis?
A. Osteogenesis imperfecta Type I
B. Classic Ehlers-Danlos syndrome
C. Arthrochalasis Ehlers-Danlos syndrome
D. Osteogenesis imperfecta Type III
E. Vascular Ehlers-Danlos syndrome
C - Arthrochalasis EDS is caused by mutation in COL1A1 or COL1A2.
Your patient presents with a blistering disease of the skin caused by defective anchoring of the epidermis to the dermis. An image of the pathology is shown here. What is your diagnosis?
A. Simplex EB
B. Dystrophic EB
C. Alport Syndrome
D. None of these
A - Simplex EB is a cytokeratin (cytoskeleton of the epidermal cells) mutation
The image displayed is characteristic of which basement membrane-related disease?
A. Simplex EB
B. Dystrophic EB
C. Alport Syndrome
D. None of these
C - Loss of kidney function, hearing loss, eye anomalies are characteristic of Alport syndrome.
