Journal of Dental Research, Vol 60, 1045-1052, Copyright © 1981 by International & American Associations for Dental Research Online Journals
The role of intracellular lysosomal enzymes in the autocellular-surveillance of unhydroxylated collagens in dermal and gingival fibroblasts
M. Roszkowski and J. J. Sauk
The turnover of unhydroxylated collagen was investigated in dermal and
gingival fibroblasts derived from C57Bl/6J mice. Unhydroxylated collagen
molecules were fostered by the inhibition of prolyl- and lysyl-hydroxylase
by the addition of alpha, alpha' dipyridyl. Turnover of collagens was
determined by single isotope continuous labeling, double-isotopic labeling,
the use of lysosomal pH modulators, and proteinase inhibitors. These
studies reveal that the turnover of unhydroxylated collagen is an
extracellular event, in spite of the susceptibility of these abnormal
structural and conformational proteins to proteolysis; the synthesizing
cell does not utilize intracellular lysosomal enzymes as a means of
modulating the quantities of non-helical unhydroxylated collagen as an
intolerable post-translational error of protein processing.
