User:Brian Conner/Sandbox 1
From Proteopedia
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'''Elastin''' | '''Elastin''' | ||
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| - | Elastin is a fibrous protein that can be found in human connective tissue and gives the tissue its elastic quality. This allows tissues that have been stretched to regain their original shape. Elastin is typically found in tissue such as skin, blood vessels, lungs, and urinary. Mature elastin is an insoluble polymer constituted by several | + | Elastin is a fibrous protein that can be found in human connective tissue and gives the tissue its elastic quality. This allows tissues that have been stretched to regain their original shape. Elastin is typically found in tissue such as skin, blood vessels, lungs, and urinary. At the cellular level elastin is found in the extracellular matix. Mature elastin is an insoluble polymer constituted by several tropoelastin molecules covalently bound to each other by cross-links. These can be bi- (lysinonorleucine), tri- (merodesmosine) or tetra-functional (desmosine and isodesmosine) in nature, and the increase in complexity is thought to progress as the fiber matures and ages. Despite its very hydrophobic nature, elastin is highly hydrated by water that swells the polymer in vivo. Mature elastin is extremely stable, and its turnover is so slow it can be assumed that elastin lasts for the entire lifespan of the organism. |
== Gene == | == Gene == | ||
Revision as of 22:17, 30 April 2014
Elastin
Elastin is a fibrous protein that can be found in human connective tissue and gives the tissue its elastic quality. This allows tissues that have been stretched to regain their original shape. Elastin is typically found in tissue such as skin, blood vessels, lungs, and urinary. At the cellular level elastin is found in the extracellular matix. Mature elastin is an insoluble polymer constituted by several tropoelastin molecules covalently bound to each other by cross-links. These can be bi- (lysinonorleucine), tri- (merodesmosine) or tetra-functional (desmosine and isodesmosine) in nature, and the increase in complexity is thought to progress as the fiber matures and ages. Despite its very hydrophobic nature, elastin is highly hydrated by water that swells the polymer in vivo. Mature elastin is extremely stable, and its turnover is so slow it can be assumed that elastin lasts for the entire lifespan of the organism.
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Gene
The elastin gene is a single copy gene localized in chromosome 7 in humans and, under normal conditions, is expressed by various cell types during the pre- and neonatal stages of development. The elastin gene product, tropoelastin, is a protein of 750 to 800 residues. As a norm, the elastin gene possesses 36 exons, some of which code for hydrophobic sequences and others for lysine-containing segments. The introns of the human gene are much larger than the exons 3 and 32 and the exon–intron boundaries always split codons in the same manner. This unique feature allows extensive alternative splicing of the primary transcripts without disrupting the reading frame 32, 52, 53 and 83 and results in the translation of various tropoelastin isoforms. Recent results show that this phenomenon is spatially and developmentally regulated. Thus, it should have some functional significance but, to date, is not fully understood.
Structure
Conventionally elastin was thought to be an amorphous polypeptide but recent break studies and breakthroughs have lead to some speculation as to some of the possible structures that could be found in elastin.
Function
Disease
Deletions and mutations in the gene that encodes for elastin can result in supraventricular aortic stenosis, and autosomal dominant cutis laxa. Other disorders that are associated with defects in elastin are Marfan's Snydrome and emphysema, which is caused by an α1-antitrypsin deficiency.
