Collagen Synthesis
covalent bonds called "_________" are formed within and between the tropocollagen molecules in the collagen fibrils and fibers of collagen
"cross links"
this enzyme causes transformation in pro-collagen molecule into a tropocollagen molecule that aggregates into fibrils then collagen fibers
collagenase
process that gives collagen its strength
cross-linking (cross-link formation)
what are some disorders where collagen synthesis impaired
Marfan syndrome Ehler-Danlos syndrome Osteogenesis imperfecta
what facilitates hydroxylation of the procollagen chain
ascorbic acid (vitamin C) Scurvy - vit C deficiency causes issues with collagen formation as hydroxylation is suppreses
where does cross-link formation occur on the tropocollagen
between and within the triple helix structures on the tropocollagen
what helps degrade collagen to be broken down by proteases and allows for proper maintenance and repair of the tissues
collagenases
Enzymatic process of stabilizing procollagen alpha chains to procollagen molecules through weak hydrogen bonds
hydroxylation
where is the procollagen (polypeptide) chain made in the fibroblast
in the RER
what is stimulated to begin collagen synthesis
integrin
what helps stimulate the production or the collagen gene for procollagen in the nucleus of the fibroblast
integrin + Growth factors --> MAPK signaling = polypeptide chain formation
what happens after post-translational modifications occur to the triple helix pro-collagen
it is secreted into the ECM by the fibroblast
how is integrin stimulated for collagen synthesis and adaptive response
mechanical loading = mechanotransduction
what are the main factors that regulate collagen synthesis
mechanotransduction and growth factors
where does the process of collagen synthesis begin
membrane of the fibroblast cell
what disease affects collagen degradation with increased collagen degrading enzymes
rheumatoid arthritis
what enhances cross-link formation of collagen
the application of controlled stressors to the tissue - collagen will align to the stress lines
what is formed during hydroxylation to help stabilize the procollagen
the triple helix structure with hydroxylated amino acids by weak hydrogen bonds
procollagen structure
three polypeptide chains coiled and held together by weak bonds into a triple helix
when is the collagen susceptible to being broken down by proteases
when tropocollagen is denatured/degraded degradation > procollagen synthesis
how do genetic defects effect collagen formation
~Genetic abnormalities in the procollagen chains ~Deficiencies of the enzymes that control post-translational processing (ie. Hydroxylation) (scurvy)