CSB327H1 Lecture Notes - Lecture 9: Intramembranous Ossification, Endochondral Ossification, Aggrecan

• School: UTSG
• Department: Cell and Systems Biology
• Course: CSB327H1
• Professor: Maurice Ringuette

Document Summary

Lp shares sequence and structural similarity to g1. Igg-like: ks chain binding region, cs chain binding region, egf-like domain, lectin-like domain, crp-like domain, one c-terminal globular domain. Transport of aggrecan from er to golgi. Ha-aggrecan aggregate: aggrecan monomers bind non-covalently to ha chain through lp and g1 dimer. Lp increases the binding affinity of aggrecan for ha than g1 alone: aggrecan monomer is packaged into a small volume of water in cartilage matrix. Creates osmotic pressure: cd44 binds ha-aggrecan aggregate in the pericellular matrix by binding to the core protein of ha, the addition of ha oligosaccharides (ha6) displaces (80% of pericellular membrane) Cd44-bound ha-aggrecan aggregates: the addition of ha oligosaccharides (ha6) cannot displace (20% of pericellular membrane left) Ha-bound aggrecan because of lp: ha oligosaccharides (ha6) can compete for binding with ha. Aggrecan-associated defects: alizarin red stains bone, alcian blue stains cartilage, nanomelia (no g3 domain) shorter trunk (base of skull to tail) length autosomal recessive.