Association of Type VI Collagen with D-Periodic Collagen Fibrils in Developing Tail Tendons of Mice.

Abstract

Summary.The process of the arrangement of Dperiodic collagen fibrils and their growth in maturing tail tendon of mice were studied with the association of type VI collagen, from fetal day 10 to 10 weeks after birth. In tail tendons, the amount of collagen fibers gradually increased along with the diameters of Dperiodic collagen fibrils during. maturation. Type VI collagens first appeared on fetal day 10, when Dperiodic collagen fibrils were not recognizable. Type VI collagens were observed around the fibroblastic cells in early stages of development, but were among thick collagen fibrils in the adult tendon. While the periodic distances of type VI collagen fibrils were over 100 nm at fetal days, they were packed to 80-90 nm after birth. The periodic bands were stained well with ruthenium red in adult but not in young tendons, indicating the close association of proteoglycans or glycosaminoglycans (PGs/GAGS) with maturing type VI collagens. Since type VI collagen in native form is known to associate with D-periodic collagen fibrils via PGs/ GAGS, ruthenium red-stainability on the surface of D-periodic collagen fibrils was also examined; results showed that ruthenium red-stainable elements were D-periodically associated.When the surface morphology of D-periodic collagen fibrils in adult animals was examined by atomic force microscopy, a large depth of the groove between elevated and depressed surfaces became prominent when the fibril surface was digested with hyaluronidase. Thus, it is possible to observe topologically the association of PGs/GAGS and probably that of type VI collagens with D-periodic collagen fibrils.

Developmental regulation of biglycan expression in muscle and tendon

“…Moreover, collagen VI gene expression in muscle shows a similar developmental pattern to that which we have observed for biglycan 19. These two molecules are also colocalized in tendon and muscle 30, 34, 29, 18. Taken together with the genetic studies discussed above, these findings raise the possibility that biglycan and collagen VI may cooperate in muscle and tendon development.…”

Identification, content, and distribution of type VI collagen in bovine tendons

“…Given its morphology and distribution in tendons, it has been attributed an integrative function, organizing collagen fibers and linking them to the cells (Bruns et al 1986). Type VI collagen has been found in the osseous attachment to the myotendinous junction of the masseter tendon (Senga et al 1995), and spatial interactions of type VI collagen, small proteoglycans, and collagen fibrils have been observed in tendons (Watanabe et al 1997). Nurminskaya and Birk (1998) have shown that type VI collagen is expressed after the fibrillogenesis phase.…”

Quantitative Trait Loci Analysis of Tail Tendon Break Time in Mice of C57BL/6J and DBA/2J Lineage

“…TypeVI collagen is present during mouse tail developmentaswellasamongthickcollagenfibrilsinthe adulttendon. (38)TypeXIcollagenisalsoexpressedinthe tailduringmousedevelopment.Theprocesswherebythe long parallel collagen fibrils are deposited into the ECM hasnotbeencompletelydescribed,butitisbelievedthata varietyofmoleculesmayaffecttailtendonstructure (31). Growth differentiation factor 5 deficiency increased the proportionofmediumdiametercollagenfibrilsintailtendon (39).NoQTLswereidentifiedintheregionsthaten-codegrowthdifferentiationfactor5.However,theeffects from QTLs that reside elsewhere but still influence this gene,forexample,throughregulatorymechanisms,cannot beexcluded.…”