proteins Flashcards
what is connective tissue
complex extracellular matrix that fills the space between cell and binds cells and tissue together
what are the functions of connective tissue
provides support and connecting frame work for all other tissue
name the three major classes of biomolecules in extracellular matrix
- the structural proteins: collagen, elastin, & fibrillin
- specialized protein: fibronectin & laminin
- proteoglycans
what are the functions of ECM
- protection: protect brain from skull
- structural support: bone
- connection & binding: ligament, tendon
- storage: bone stores ca & p
- transportation: blood
- immune function: WBC
name the elastic protein found in tissue where stretch is needed
elastin
elastin is a ___________ polypeptide that contain _________ fiber as major component
a) beta plates, , collagen
b) alpha chain, fibronectin
c) linear, elastic
c) linear, elastic
what are the properties of elastin
stretch and resume their original length
high tensile structure
where can we find elastin
Elastic ligaments, walls of arteries, lungs and vocal cord, epiglottis, ligamenta flava
Smaller quantities found in skin, ear cartilage etc.
elastin is rich in ______________amino acids
nonhydroxylated proline, lysine, glycine
unlike collagen elastin can exist on _______________ forms
no glycosylated
tropoelastin with fibrillin forms
scaffolding
cross linking occurs extracellularly via
lysyl oxidase
lysyl oxidase gives elastin what property
elastic property
describe the structure of elastin
highly cross linked insoluble, amorphous structure
true or false
hydroxyproline (1%) present, but no hydroxylysine.
true
which protein bind to tropoelastin to form elastic fiber
fibrillin
name the enzymes that can degrade elastin protein
elastase enzyme such as neutrophil-elastase
what inhibits a no of protease including neutrophil-elastase
α1- antitrypsin
what is α1- antitrypsin
is a class of protease inhibitors that normally inhibits elastase
α1-antitrypsin is synthesized by
liver
α1-Antitrypsin deficiency results in
unopposed elastase activity, which can cause COPD
PANACINAR Emphysema caused by
deficiency of α1- antitrypsin.
deficiency of α1- antitrypsin. can cause
loss of inhibitory action on neutrophil elastase
excessive destruction of elastin in lung alveolus
excess elastase activity
name the disease
-severe in the lower lobes
-associated with 𝜶1-antitrypsin deficiency but can also be found in patients in whom no genetic abnormality has been identified.
panacinar emphysema
which type of emphysema is usually predominates in the upper lobes
centriacinar emphysema
glycoprotein that cell adhesion & migrate
fibronectin
insoluble monomers involved in linking in
cell surface integrins to ECM
state two characteristics of fibronectin
soluble protein
assists in blood clotting
what is sequence of aa that binds to the receptor of fibronectin
Arg-Gly-Asp
what are the functions of fibronectin
-binding heparin fibrilin and collagen
-cell migration
-cell morphology
-embryogenesis
-cytoskeletal organization
-attach cells to various components of the ECM
-can circulate in plasma to assist with clotting
-biofilm formation via cell adhesion to basement membrane
name the abnormality that cause early onset of scoliosis and skeletal abnormalities
spondylometaphyseal dysplasia
spondylometaphyseal dysplasia is associated with
mutation in fibronectin
which protein is the only one that exists as an insoluble dimer as well as a soluble clotting factor
fibronectin
which is the major protein component of renal glomerular and other basal laminas
laminin
how many elongated polypeptide chains in laminin
3
α, β1, β 2
shape of laminin protein
cruciform shape
what are the binding sites of laminin
type 4 collagen, heparin & integrins on cell surface and entactin (nidogen)
what is fibrillin
a glycoprotein found in many tissue
fibrillin is secreted into ____________ by _________
ECM, Fibroblast
which protein provides a scaffold for deposition of elastin
fibrillin
name the disease caused by mutation in the gene coding for fibrillin on chromosome 15
marfans disease
Marfans disease is inherited as an ____________ trait
autosomal dominant trait
name the disease that affect eyes and cause ectopia lentis
marfans disease
name the disease has following presentations
long extremities including fingers
scoliosis
myopia and lens dislocation (upward dislocation)
marfans disease
what is scoliosis
sideways curvature of the spine (often diagnosed in adolescent)
how marfan’s syndrome affect skeletal system
hyper extensibility of joints, tall sature
how marfan’s syndrome affect CVS
dilatation of aorta( aortic aneurysm and dissection)
deficiency of which enzyme cause homocystinuria
cystathionine synthase deficiency
symptomsw
difference
what is proteoglycans
they are protein that contain covalently linked glycosaminoglycans
major component of ECM
proteoglycans are formed by polysaccharide called
glycosaminoglycans( GAH, 95%), protein (1%)
