2-Connective tissue and articulations Flashcards
Name 4 major proteins found in the ECM
Collagen, Adhesin, Fibrillin, Elastin
Describe the structure of collagen
Triple helix of Glycine-X-Y (X usually proline, Y usually hydroxyproline) forming tropocollagen
Tropocollagens align in a staggered manner to form collagen fibrils.
Collagen fibrils associate laterally and end to end
Why does scurvy occur?
Hydroxylation of peptide chains in collagen requires prolyl and lysine hydroxylase, which need vitamin C as a cofactor. Lack of vitamin C = collagen becomes unstable
What is elastin and what do mutations cause?
Elastin fibres can stretch when hydrated and return to normal length. Comprise ligaments, large vessels and skin. Polymer of tropoelastin monomers.
Mutations cause cutis laxa (lax skin)
What is fibrillin and what do mutations cause?
Glycoprotein essential for formation of elastic fibres. Forms bundles or microfibrils surrounding an elastin core
Fibrillin 1=Marfan’s Syndrome
Fibrillin 2=arachnodactyly
What is the main proteoglycan in type 2 cartilage?
Aggrecan
What is a synarthrosis?
Type of joint found in the suture lines of skulls where adjacent plates are separated by a thin fibrous tissue?
What is an amphiarthrosis?
Type of joint found in the pubic symphysis or SI joint. Adjacent bones are bound by flexible cartilage (allowing a small range of movement)
What is a diarthrosis?
Synovial joint, including ball and socket, hinge, plane, saddle
Synovial fluid is rich in what?
Hyaluronic acid
What disease is caused by type 1 collagen mutations and what is its inheritance pattern?
Osteogenesis imperfecta. Autosomal dominant
What disease is caused by problems with collagen synthesis or enzymatic modification and what is its inheritance pattern?
Ehlers-Danlos. Autosomal dominant (except for type 6)
