extracellular matrix Flashcards
extracellular matrix (ECM): recall the definition and function of, the ECM; and explain the relationship between the ECM and connective tissues, recall examples of human disorders resulting from ECM pathology
define extracellular matrix
complex network of carbs and proteins (fibrillar and non-fibrillar) surrounding cells in tissues which can interact with cell receptors
functions of extracellular matrix
mechanical support; influence growth, adhesion, differentiation
composition of connective tissue
epithelium → fibroblast → smooth muscle → fibroblast → epithelium
function of fibroblast
make extracellular matrix components; main support cell of connective tissue
basal lamina function
separates underlying connective tissue from epithelial cells
extracellular matrix components within connective tissue
collagens, multi-adhesive glycoproteins, proteoglycans
what type of collagen are located in the basement membrane
type IV
what type of collagen are located in the extracellular matrix
fibrillar collagen I-III
what glycoprotein is located in the basement membrane
laminin
what glycoprotein is located in the extracellular matrix
fibronectin
what proteoglycan is located in the basement membrane
perlecan
what proteoglycans are located in the extracellular matrix
dectin and versican
what affects the function of connective tissue regarding the extracellular matrix
composition and arrangement of extracellular matrix e.g. tendon and skin; bone; cartilage; vitreous humour (eye)
examples of gene mutations on extracellular matrix proteins
Marfan’s syndrome, osteogenesis imperfecta, Alport’s syndrome, epidermolysis bullosa, congenital muscular dystrophy
mutated protein in Marfan’s syndrome
fibrillin-1
mutated protein in osteogenesis imperfecta
type I collagen
mutated protein in Alport’s syndrome
type IV collagen
mutated protein in epidermolysis bullosa and congenital muscular dystrophy
laminin
example of gene mutation on extracellular matrix catabolism
Hurler’s syndrome
examples of fibrotic disorders due to excessive extracellular matrix deposition leading to replacement with collagen
cirrhosis, kidney fibrosis, lung fibrosis
what causes kidney fibrosis
diabetic nephropathy
what causes lung fibrosis
silicosis
example of fibrotic disorders due to excessive loss of extracellular matrix
osteoarthritis
osteoarthritis
loss of extracellular matrix (cartilage) in joints as aggrecan degrades and is lost to synovial fluid
