Fibrillin microfibrils elasticity

Fibrillin microfibrils are widely distributed extracellular matrix assemblies that endow elastic and non elastic connective tissues with long-range elasticity. They direct tropoelastin deposition during elastic fibrillogenesis and form an outer mantle for mature elastic fibers. Microfibril arrays are also abundant in dynamic tissues that do not express elastin, such as the ciliary zonules of the eye. Mutations in fibrillin-1—the principal structural component of microfibrils—cause Marfan syndrome, a heritable disease with severe aortic, ocular, and skeletal defects. Isolated fibrillin-rich microfibrils have a complex 56 nm beads-on-a-string appearance the molecular basis of their assembly and... 

Fibrillin-rich microfibrils have endowed tissues with elasticity throughout multicellular evolution. X-ray studies and mechanical testing of microfibril bundles showed that bound calcium influences load deformation, but is not necessary for high extensibility and elasticity (Eriksen et al, 2001 Wess et al, 1997, 1998a,b). Thus, tissue microfibril elasticity is modified by, but not dependent on, calcium-induced beaded periodic changes. This is consistent with the molecular folding model. 

Kielty, C. M., Sherratt, M.J., Haston,J. L., Wess, T. J., and Shutdeworth, C. A. (2002a). Fibrillin-rich microfibrils Elastic biopolymers of the extracellular matrix. J. Muscle Res. Cell Motil. 23, 581-596. 

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]... 

Qian, R. Q., and Glanville, R. W. (1997). Alignment of fibrillin molecules in elastic microfibrils is defined by transglutaminase-derived cross-links. Biochemistry 36, 15841-15847. 

Sherratt, M. J., Holmes, D. F., Shuttleworth, C. A., and Kielty, C. M. (1997). Scanning transmission electron microscopy mass analysis of fibrillin-containing microfibrils from foetal elastic tissues. Int. J. Biochem. Cell Biol. 29, 1063-1070. 

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-... 

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. 

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. 

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