Collagens functions

The NCI domain of type VII collagen binds to the /33 chain of laminin, " laminin-5 a3(33 2), and type IV collagen. The triple helical domain of type VII collagen functions to promote the migration of human keratinocytes. °... 

Collagen functions and types Gene name Polvpeptide composition... 

Collagen has an a-helical secondary structure. Collagen functions as the raw material from which tendons are constructed. 

Fibrous proteins can serve as structural materials for the same reason that other polymers do they are long-chain molecules. By cross-linking, interleaving and intertwining the proper combination of individual long-chain molecules, bulk properties are obtained that can serve many different functions. Fibrous proteins are usually divided in three different groups dependent on the secondary structure of the individual molecules coiled-coil a helices present in keratin and myosin, the triple helix in collagen, and P sheets in amyloid fibers and silks. 

A simplest possible flow-model (Fig. 11.1) has been formulated to account for collagen and for bioapatite carbonate measurements, under conditions where the protein content in the diet is changing. Its predictions , in terms of the Dietary Isotope Fractionation Function (DIFF), have been made explicit. 

Figure All.l. A plot of the difference (residuals) between observed collagen 5 C values and values calculated from the DIFF for dp = +5, dn = +2, and f(F) = F , as a function of the dietary protein carbon content. Due to the eombination of eomposition and manipulated isotopic compositions of the different diets, some diets test the predictions of the DIFF more precisely than others. These are represented as squares (the remainder are represented as diamonds). Although the differenee has been minimized, it is not zero. Nevertheless, and especially for the more reliable reetangular points, the differenee is small, for a wide range of diets and collagen 8 values. Other combinations of dp, ds. and 1(F) give greater residuals.

Gelse, K, Poschl, E., Aigner, T. (2003). Collagens - structure, function, and biosynthesis. Advanced Drug Delivery Reviews, Vol. 55, pp. 1531-1546. 

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