The effect of bovine tendon glycoprotein on the formation of fibrils from collagen solutions

Abstract

The formation of collagen fibrils under physiological conditions of ionic strength, pH and temperature was markedly affected by the presence of small amounts of bovine tendon glycoprotein. The absorbance of the gels at 400nm was decreased, and they took longer to form. Over the range of concentration tested, the negative specific absorbance, -AA,p., and the specific retardation, Rs,., both increased with the glycoprotein to collagen ratio.When added during the nucleation phase, glycoprotein was still able to exert its effect almost fully, and so must act to inhibit the later stages of fibril formation. Several pieces of evidence showed that glycoprotein acts via a weak binding to the collagen molecule. Electron microscopy established that fibrils formed in the presence of glycoprotein had a normal cross-striation pattern, but were significantly thinner than fibrils formed in control gels. The results suggest that glycoprotein could act in tissues to help regulate the diameter of collagen fibrils.

Biochemical and morphological modifications in rabbit Achilles tendon during maturation and ageing

“…At the same time, the average diameter of collagen fibres increases, as described by several authors, during tendon maturation (Fitton-Jackson, 1956;Schwartz, 1957;Torp et al, 1975;Hall, 1976;Parry & Craig, 1978;Scott et al, 1981a,b). Anderson et al (1977) postulated that structural glycoproteins could regulate the diameter of collagen fibrils by modulating the aggregation of tropocollagen molecules; in fact he showed that the increase in diameter is preceded by a loss of structural glycoproteins. We confirmed their results and demonstrated, in addition, a clear variation of the content of hydroxylysyl glycosides, supporting also the hypothesis of Morgan et al (1970) that an inverse correlation exists between the carbohydrate content of collagen and fibril diameter.…”

“…A soluble glycoprotein closely associated with the proteodermatan sulphate fraction was also extracted and purified (Anderson, 1975). This molecule appeared to be able to affect in vitro the formation of collagen fibrils by decreasing their growing rate (Anderson et al, 1977).A similar effect can be exerted by glycosaminoglycans; in fact, Keech (1961), while studying the appearance under the electron microscope of collagen fibrils regenerated from solution, observed that the presence of chondroitin sulphate in the precipitating medium greatly increased the rate of fibril 11 To whom correspondence and requests for reprints should be sent.Vol. 204formation and lowered their diameter by a factor of 3.…”

“…A soluble glycoprotein closely associated with the proteodermatan sulphate fraction was also extracted and purified (Anderson, 1975). This molecule appeared to be able to affect in vitro the formation of collagen fibrils by decreasing their growing rate (Anderson et al, 1977).…”

Zur Ultrastruktur kollagener Fibrillen in normalen und veränderten Blutgefässen

“…Im Gegensatz zum Marfan-Syndrom scheint sich das Kollagentypenverhältnis bei arteriosklerotischen Gefässwanderkrankun-gen zugunsten von Typ-I-Kollagen zu ver schieben [McCullagh und Balian, 1975;McCallagh et al, 1980] [Anderson et al, 1977;Minor, 1980;Podrazky, 1981] …”

Studies of the intercellular matrix of growth plates from dwarf and homozygous nonaffected alaskan malamutes: Collagen and hexosamine

“…Chondroitin 4-sulfate, chondroitin 6-sulfate, and keratan sulfate are the major glycosaminoglycans found in skeletal cartilage proteoglycans. Proteoglycans are thought to form a directing framework for the formation of collagen fibrils [14,15]. They also form large aggregates associated with the collagen fibrils and bind large volumes of water which gives cartilage its unique property of high viscoelasticity.…”