Collagen Flashcards
3 main tissues in connective tissues
- collagen
- elastin
- proteoglycans
3 main properties of collagens
- tensile strength
- compression resistance
- specialized networks
what is at ends of collagens
registration peptides
featuure of collagen chain
Gly-X-Y
What allows 3 helix structure
registration peptides @ C-terminal + Gly/x/y repeat
what keeps strand together after peptides cleaved off
H-bond > tropocollagen
what links 2 triple chains
lysine and hydroxylysine covalent crosslinks
what a group of many chains together create
quarter stagger array
3 types of collagen fiber org. and their locations
- unidirectional - tendon
- random - skin
- orthoganal - cornea
what happens if don’t convert proline to hydroproline
no H-bonds - loose joints, teeth fall out, weak bones - scurvy
what is needed to convert proline to hydroxyproline
Fe - vit C
what happens if don’t convert lysine to hydroxylisine (lacking Vit. C)
Ehlers Daniels Type 6
- super extensible skin, joint laxity, detached lenses
what happens if fail to remove N-registration peptide
Ehlers Daniels Type 7
- interferes with collagen fiber packing
- skin brittle, congenital dislocations
what happens if fail to form lysine/hydroxylisine cross-link
cutis laxa - decreased crosslinking - loose floppy skin - sharpei
causes of fail to form lysine/hydroxylisine cross-link
defects in copper metbolism
2 major types of genetic collagen
- continuous - types 1,2,3
2. discontinuous - types 4
locations of Type 1 collagen
skin, bone, tendon, ligament
locations of Type 2 collagen
cartilage, cornea,
locations of Type 3 collagen
fetal skin, vasuclar tissues
locations of Type 4 collagen
basement membrane
feature of discontinuous collagen
registration peptide not removed
cause of chondroplasias
mutations in type 2,9,10,11
consequences of chondroplasia
malformations in articular cart
joint deformities
familial osteoartritis
what happens for mutations in type 3 coll.
EDS type 4 - most severe phenotype
- thin translucent skin
- fragile blood vessels