Fibril diameter

Col Hal null mice have fibril diameter abnormalities in the early postnatal stage but the adult showed no significant differences. Type XIV collagen might function early in development regulating the entry of fibril intermediates into lateral fibril growth. ... 

Types III, V, and XI—may decorate fibril surfaces with their partially processed N-terminal regions. A possible role of these moieties in the regulation of fibril diameter is discussed later. 

Type V collagen integration in corneal tissue from both avian and mammalian sources points to heterotypic collagen interactions providing some basis for fibril diameter regulation (White et al, 1997). Indeed, the triple-helical structure of Type V collagen alone has been shown to be an important factor in regulating the fibril diameter of Type V/Type I heterotypic fibrils in vitro (Adachi and Hayashi, 1986). 

Work by Haston et al. (2002) also indicates that acidic glycoprotein (AGP) influences Type II collagen fibrillogenesis, where in vitro studies show that low concentrations of AGP produced decreases in fibrillogenesis rate and fibril diameter. High concentrations produced fibrils at a rate and diameter dependent on fucosylation of AGP. Highly fucosylated AGP produced narrow fibrils, and poorly fucosylated AGP produced thicker fibrils. 

Care has to be taken in comparing fibril diameter information from a variety of sources, since sample preparation and the ability of the... 

Bradshaw, A. D., Puolakkainen, P., Dasgupta, J., Davidson, J. M., Wight, T. N., and Sage, E. H. (2003). SPARC-null mice display abnormalities in the dermis characterized by decreased collagen fibril diameter and reduced tensile strength. J. Invest. Dermatol. 120, 949-955. 

Sanders, J. E., and Goldstein, B. S. (2001). Collagen fibril diameters increase and fibril densities decrease in skin subjected to repetitive compressive and shear stresses. J. Biomech. 34, 1581-1587. 

Surfaces can do more than stimulate the growth of amyloid fibrils the presence of a surface during assembly can also influence fibril morphology. Fibril diameter has been observed to be smaller on surfaces than in the bulk for some polypeptide systems (Zhu et al., 2002). This may be due to the constraints imposed by the surface or could result from a different mechanism of fibril growth. The shape of fibrils formed on surfaces can also differ to the shape of fibrils formed in the bulk solution. 

Primitive and mature fibril diameter Craze thickening rate Fibril lifetime... 

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