- See:
- Disorders
- Ligament Healing Characteristics:
- Discussion:
- collagen is the primary structural protein of the body & occurs in bone, tendon, and scar tissue as well as in cartilage;
- at least nineteen distinct gene products have been identified in humans, for different types of collagen, that differ by amino acid
structure of alpha chains;
- their composition differs slightly in different species, but its general function is the same in all;
- biosynthesis of collagen
- type I collagen: bone, tendon, skin, menisci
- type II collagen:
- fibrils of type II collagen account for > 50 % of dry wt of cartilage;
- Examples: Articular cartilage and Nucleus pulposus of intervertebral disc
- type II collagen is also found in small amounts in the vitreous gel and in a number of other tissues during early development;
- examples of type II collagen disorders:
- achondrogenesis
- SED
- type III collagen:
- type III collagen is found in small amounts in many tissues in association w/ type I collagen & is major component of large
blood vessels; skin
- type IV collagen, one of the nonfibrillar collagens, is a major constituent of all basement membranes;
- type V and VI collagen
- articular cartilage (small amounts)
- type V Collagen . .J. Leeming, M.A. Karsdal, in Biochemistry of Collagens, Laminins and Elastin, 2016
- Features Suggesting a Skeletal Tissue Disorder Versus JIA WG. Cole, O Mäkitie, in Textbook of Pediatric Rheumatology, 2016
- Ehlers–Danlos Syndrome Peter H. Byers, in Emery and Rimoin's Principles and Practice of Medical Genetics, 2013
- Ehlers–Danlos Syndrome Salahuddin Kazi, in Encyclopedia of Gastroenterology, 2004
- type VII and VIII collagen, epithelial basement membranes
- type IX collagen:
- these molecules surround the surface of the type-II collagen fibrils and covalently cross-linked to them;
- these molecules may mediates the interaction of type-II collagen with surroundingr extracellular matrix components;
- MED
- type X collagen production:
- short-chain collagen found only in the hypertrophic zone;
- mutations here may cause Schmid metaphyseal chondrodysplasia;
- associated with matrix mineralization (calcification)
- type XI, also articular cartilage,
- type XII, tendon
- Microscopic Characteristics:
- in different tissues, size of the collagen fibers varies markedly;
- as measured by light microscopy, diameter of tendon fiber may be several hundred microns, whereas in loose connective tissue it
may be only 1;
- w/ the electron microscope, finer fibers called fibrils vary from 20 nm to less to 50 or 60 nm;
- arrangement of these fibrils and their size characterize different tissues
Development of a reconstituted collagen tendon prosthesis. A preliminary implantation study.
A type X collagen mutation causes Schmid metaphyseal chondrodysplasia.