Aumailley M, Krieg T, Razaka G, Müller P K, Bricaud H
Biochem J. 1982 Sep 15;206(3):505-10. doi: 10.1042/bj2060505.
Characteristic features of collagen metabolism in human skin fibroblasts were studied in relation to cell density. Measuring peptide-bound hydroxyproline we found that collagen synthesis per cell decreased when cultures approached confluency. On the other hand, the relative rate of collagen synthesis (collagen/total protein) was higher in quiescent than in proliferating cultures. With increasing cell density the proportion of type III collagen in comparison with type I was found to be slightly increased. In addition, in low-density cultures [alpha I(I)]3 collagen trimers were produced in considerable amounts, whereas they were no longer detected in cultures with a high cell density. Although hydroxylation of proline residues was normal in all cell stages, conversion of procollagen into collagen was found to depend strongly on the density at which the cells were investigated. Almost no cleavage of procollagen peptides was observed in rapidly growing cells, whereas highly confluent cell cultures converted most of the newly synthesized procollagen molecules.
我们研究了人皮肤成纤维细胞中胶原蛋白代谢的特征与细胞密度的关系。通过测量肽结合羟脯氨酸，我们发现当培养物接近汇合时，每个细胞的胶原蛋白合成减少。另一方面，静止培养物中胶原蛋白合成的相对速率（胶原蛋白/总蛋白）高于增殖培养物。随着细胞密度的增加，发现III型胶原蛋白与I型胶原蛋白相比的比例略有增加。此外，在低密度培养物中会产生大量的[αI（I）]3胶原蛋白三聚体，而在高细胞密度的培养物中则不再检测到。尽管脯氨酸残基的羟基化在所有细胞阶段都是正常的，但发现前胶原转化为胶原蛋白强烈依赖于所研究细胞的密度。在快速生长的细胞中几乎没有观察到前胶原肽的切割，而高度汇合的细胞培养物则将大部分新合成的前胶原分子进行了转化。
