Type I collagen is the most abundant
collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whol ...
of the human body. It forms large, eosinophilic fibers known as collagen fibers.
It is present in
scar tissue
Scar tissue may refer to:
Medicine
* Scar, an area of fibrous tissue that replaces normal skin after injury
* Granulation tissue, a product of healing in major wounds
Film and television
* ''Scar Tissue'' (1975 film), or ''Wanted: Babysitter'' ...
, the end product when tissue
heals by repair, as well as
tendons
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its abilit ...
,
ligaments
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the:
* Peritoneal ...
, the
endomysium
The endomysium, meaning ''within the muscle'', is a wispy layer of areolar connective tissue that ensheaths each individual muscle fiber, or muscle cell. It also contains capillaries and nerves. It overlies the muscle fiber's cell membrane: th ...
of
myofibrils
A myofibril (also known as a muscle fibril or sarcostyle) is a basic rod-like organelle of a muscle cell. Skeletal muscles are composed of long, tubular cells known as muscle fibers, and these cells contain many chains of myofibrils. Each myofi ...
, the organic part of
bone
A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, ...
, the
dermis
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided ...
, the
dentin
Dentin () (American English) or dentine ( or ) (British English) ( la, substantia eburnea) is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by e ...
, and organ capsules.
Formation
The gene produces the
pro-alpha1(I) chain. This chain combines with another pro-alpha1(I) chain and also with a pro-alpha2(I) chain (produced by the gene) to make a molecule of type I pro-collagen. These triple-stranded, rope-like pro-collagen molecules must be processed by enzymes outside the cell. Once these molecules are processed, they arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-links result in the formation of very strong mature type I collagen fiber.
Clinical significance
See
Collagen, type I, alpha 1#Clinical significance
Markers used to measure bone loss are not easily testable. Degradation of type 1 collagen releases metabolites that can be used to monitor resorption.
See also
*
Collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whol ...
*
Type II collagen
Type II collagen is the basis for hyaline cartilage, including the articular cartilages at joint surfaces. It is formed by homotrimers of collagen, type II, alpha 1 chains.
It makes up 50% of all protein in cartilage and 85–90% of collagen of ...
*
Collagen, type I, alpha 1
Collagen, type I, alpha 1, also known as alpha-1 type I collagen, is a protein that in humans is encoded by the gene. ''COL1A1'' encodes the major component of type I collagen, the fibrillar collagen found in most connective tissues, includin ...
*
Collagen, type I, alpha 2
Collagen alpha-2(I) chain is a protein that in humans is encoded by the ''COL1A2'' gene.
This gene encodes one of the chains for type I collagen, the fibrillar collagen found in most connective tissues. Mutations in this gene are associated with ...
*
Collagen, type III, alpha 1
References
Further reading
*
External links
*
Collagens
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