QS ECM PDF

QS Where is collagen found in the body? Skin, bone, cartilage, tendons, ligaments, blood vessels, cornea Where is elastin found in the body? Ligaments, lungs, wall of blood vessels what is the main unit of elastin? Tropoelastin Why does elastin have elastic properties? 3 allysine residues interac...

QS Where is collagen found in the body? Skin, bone, cartilage, tendons, ligaments, blood vessels, cornea Where is elastin found in the body? Ligaments, lungs, wall of blood vessels what is the main unit of elastin? Tropoelastin Why does elastin have elastic properties? 3 allysine residues interact with 1 unoxidized lysine to form desmosine —> desmosine is the reason for elastic properties What is the shape of elastin? Fibrous when extended and globular when relaxed What is the importance of a-1 anti-trypsin deficiency? Protects tissues from elastase enzymes from inflammatory cells (neutrophils) Why do proteinases like trypsin and elastase get secreted? When the body reacts to acute inflammation (bacterial infection) the inflammatory cells secrete proteinases What happens in the absence of a-1 anti-trypsin? Neutrophil elastase breaks down elastin —> damages lung elasticity —> respiratory complications: (Emphysema, COPD, Cirrhosis of liver) What is Fibronectin? Major protein of the ECM Where is fibronectin found? Connective tissue, plasma What is fibronectins structure? 2 subunits (identical) connected by a 2 disulfide bond, also has several binding sites What does fibronectin bind with? Heparin, collagen, cell surface receptors (integrin) What is fibronectins importance? It has adhesive characteristics which allows it to adhere with transmembrane receptors like integrin that interacts with proteins like collagen (EC) and actin (IC). Exterior and interior of the cell can communicate What is fibronectin glomerulopathy? Mutation of the gene coding fibronectin What are the effects of Fibronectin glomerulopathy? Abnormal fibronectin in glomeruli of kindeys —> abnormal glomerular structure/functions What are the manifestations of Fibronectin glomerulopathy? HPH 2R: Hematuria, Proteinuria, Hypertension, Renal tubular acidosis, Renal failure What is Fibrillin? Glycoprotein secreted into ECM by fibroblasts Where is fibrillin found? Suspensory ligaments of lens, aorta What is the importance of fibrillin? Forms scaffold for deposition of elastin What is the cause of Marfan’s syndrome? Mutation of gene encoding for fibrillin What are the manifestations for Marfan’s syndrome? Dislocation of lens, dilatation of aorta, hyperextensibility of joints What are cartilage proteins and what are they classified into? Cartilage is avascular CT and classified into Collagen and non-collagenous proteins What is the main collagen protein? Collagen type II What is collagen type II? It’s 98% of total collagen in cartilage and contains more hydroxylysine and glycosylation What is the most important non collagenous protein in cartilage? Proteoglycans (aggrecans), contains KCH (GAGs) What do the GAGs in cartilage look like? The 3 are attached to a core protein and have a bottle brush appearance Who is the binder in Cartilage proteins? Chondronectin binds type II collagen What are bone proteins and what are they classified into? Mineralized CT and classified into collagen and non-collagenous proteins What is the most important collagen protein in bone proteins? Collagen type I (90% of total collagen in bone) What is the major non collagenous protein in bone proteins? Osteocalcin Who is the binder in Bone proteins? Osteonectin binds collagen What is Osteoporosis? Progressive reduction of bone mass/density What are risk factors of osteoporosis? AFFSIL SD: Aging, Female, Family history, Sedentary life, Intake of caffeine and soda, Low intake of Ca/Mg/Vitamin D, Smoking, Drugs like corticosteroids