is a protein
in connective tissue
that is elastic
and allows many tissues in the body to resume their shape after stretching or contracting. Elastin helps skin to return to its original position when it is poked or pinched. Elastin is also an important load-bearing tissue in the bodies of mammals and used in places where mechanical energy is required to be stored.
Elastin is primarily composed of the amino acids glycine
, and proline
. It is a specialized protein with a molecular weight of 64 to 66 kDa
, and an irregular or random coil conformation made up of 830 amino acids.
Elastin is made by linking many soluble tropoelastin protein molecules, in a reaction catalyzed by lysyl oxidase, to make a massive insoluble, durable cross-linked array. The amino acid responsible for these cross-links is lysine.
Desmosine and isodesmosine are both found in elastin.
Locations in body
Elastin serves an important function in arteries
and is particularly abundant in large elastic blood vessels such as the aorta
. Elastin is also very important in the lungs
, elastic ligaments
, the skin
, the bladder
, elastic cartilage
, and the intervertebral disc
above the sacroiliac
. It is present in all vertebrates above the jawless fish .