Glycoproteins fibrillins

The amorphous elastin is organized into elastic fibers with a sheath of microfibrils surrounding each 10 nm fiber. The major component of the sheath is the glycoprotein fibrillin, mutations in whose gene causes Marfan syndrome. 

Function and location of elastin Cause of Marfan syn drome Elastin is a connective tissue protein with rubber-like properties. Elastic fibers composed of elastin and glycoprotein microfibrils, such as fibrillin, are found in the lungs, the walls of large arteries, and elastic ligaments. [Note Mutations in the fibrillin gene are responsible for Marfan syndrome]... 

Gibson, M. A., Finnis, M. L., Kumaratilake, J. L., and Cleary, E. G. (1998). Microfibril-associated glycoprotein-2 (MAGP-2) is specifically associated with fibrillin-containing microfibrils and exhibits more restricted patterns of tissue localisation and developmental expression than its structural relative MAGP-1./ Histochem. Cytochem. 46, 871-885. 

Henderson, M., Polewski, R., Fanning, J. C., and Gibson, M. A. (1996). Microfibril-associated glycoprotein-1 (MAGP-1) is specifically located on the beads of the beaded-filament structure for fibrillin-containing microfibrils as visualized by the rotary shadowing technique./. Histochem. Cytochem. 44, 1389-1397. 

Elastic fibers form the network in skin and cardiovascular tissue (elastic arteries) that is associated with elastic recovery. Historically the recovery of skin and vessel wall on removal of mechanical loads at low strains has been attributed to elastic fibers. Elastic fibers are composed of a core of elastin surrounded by microfibrils 10 to 15 nm in diameter composed of a family of glycoproteins recently termed fibrillins. Fibrillins are a family of extracellular matrix glycoproteins (MW about 350,000) containing a large number of cysteine residues (cysteine residues form disulfide crosslinks). Several members of the family have been described. The common molecular features include N and C terminal ends with 47 tandemly repeated epi-... 

Elastin is the major protein found in elastic fibers, which are located in the ECM of connective tissue of smooth muscle cells, endothelial and microvascular cells, chondrocytes, and fibroblasts. Elastic fibers allow tissues to expand and contract this is of particular importance to blood vessels, which must deform and reform repeatedly in response to the changes in intravascular pressure that occur with the contraction of the left ventricle of the heart. It is also important for the lungs, which stretch each time a breath is inhaled and return to their original shape with each exhalation. In addition to elastin, the elastic fibers contain microfibrils, which are composed of a number of acidic glycoproteins, the major ones being fibrillin-1 and fibrillin-2. 

Relatively few studies are available on the effects of vitamin C on synthesis and secretion of matrix molecules apart form collagen and elastin however, in a number of studies occasional mention is found of fibronectin, proteoglycans, bone matrix glycoproteins, and elastin-associated fibrillin (Schwartz et al, 1982 Kielty and Shuttleworth, 1993). 

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