Type III collagen

Co-expression of the human a- and p-subunits in the yeast Pichea pastoralis produces only trace amounts of active tetramer, with the majority being present in an unassembled form. Co-expression with human type III collagens, however, increases this assembly level tenfold. This indicates that collagen synthesis and the formation of an active prolyl 4-hydroxylase complex are mutually dependent processes (Vuorela et al, 1997). A similar observation has been noted for baculovirus encoded enzymes in insect cells (Lamberg et al, 1996). These findings support the hypothesis that this unusual control mechanism may be a common feature of collagen synthesis in all cell types. 

Bachinger, H.P. (1987) The influence of peptidyl-prolyl cis-trans isomerase on the in vitro folding of type III collagens. Journal of Biobgical Chemistry 262, 17144-17148. 

Bachinger, H.P., Bruckner, P., Timpl, R., Prockop, D.J. and Engel, J. (1980) Folding mechanism of the triple helix in type-III collagen and type-III pN-collagen role of disulfide bridges and peptide bond isomerisation. European Journal of... 

Lamberg, A., Helaakoski, T., Myllyharju, J., Peltonen, S., Notbohm, H., Pihlajaniemi, T. and Kivirikko, K.I. (1996) Characterization of human type III collagen expressed in a baculovirus system - production of a protein with a stable triple helix requires coexpression with the two types of recombinant prolyl 4-hydroxylase subunit.Journal of Biological Chemistry 271, 11988-11995. 

A series of short peptide fragments of type III collagen have been used to find binding sites with other molecules. DDR-2 has been shown to interact with a type III collagen model peptide with the minimal sequence of GVMGFO (where O is 4-hydroxyproline)." It is interesting to note that this same sequence is also involved with the collagen interaction of SPARC." ... 

To study the nucleation step for the folding of collagen, a protocol has been developed for the liquid-phase synthesis by which three peptide strands are covalently linked via a C-terminal branch. 70-73 The C-terminal branch is expected to enhance triple-helical thermal stability, and to provide a model of the disulfide-linked C-terminus of type III collagen. 71 ... 

Type III collagen Monoclonal antibody GLAGAOGLR Glattauer et al, 1997... 

Glattauer, V., Werkmeister, J. A., Kirkpatrick, A., and Ramshaw, J. A. M. (1997). Identification of the epitope for a monoclonal antibody that blocks platelet aggregation by type III collagen. Biochem. J. 323, 45 9. 

The structures of the Type III and V collagen telopeptides have been less studied. However, the NMR study of Type III telopeptides has been reported, and the 22-amino-acid G-terminal telopeptide is extended with a tight turn involving residues 8-11 (Liu et al., 1993). Crosslink analysis reveals connectivity between the G-terminal telopeptide of Type III collagen and the N-terminal helical region of another Type III molecule (Henkel, 1996). 

Henkel, W. (1996). Cross-link analysis of the C-telopeptide domain from type III collagen. Biochem. J. 318, 497-503. 

Henkel, W., and Glanville, R. W. (1982). Covalent crosslinking between molecules of type I and type III collagen. The involvement of the N-terminal, nonhelical regions of the alpha 1 (I) and alpha 1 (III) chains in the formation of intermolecular... 

Numerous skin sites are possible for noninvasive near-infrared measurements.40 Examples proposed in the literature include the inner lip mucosa,26 finger,41 forearm, and tongue. In all cases, the principal spectral features of the noninvasive spectra correspond to the extent of scattering superimposed on absorption bands that originate from water, protein, and fatty tissue within the skin matrix.44,45 To a first approximation, noninvasive near-infrared spectra of skin can be fitted to a Beer-Lambert function that incorporates the additive features of absorption due to water, fat, (3-sheet protein, and type III collagen, with additional terms for tissue scattering (offset) and small temperature variations (a slope term). This function takes the following form ... 

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