Barone L M, Faris B, Chipman S D, Toselli P, Oakes B W, Franzblau C
Biochim Biophys Acta. 1985 Jun 18;840(2):245-54. doi: 10.1016/0304-4165(85)90125-4.
The protein composition in the extracellular matrix of cultured neonatal rat aortic smooth muscle cells has been monitored over time in culture. The influence of ascorbate on insoluble elastin and collagen has been described. In the absence of ascorbate, the cells accumulate an insoluble elastin component which can account for as much as 50% of the total protein in the extracellular matrix. In the presence of ascorbate, the amount of insoluble collagen increases, while the insoluble elastin content is significantly less. When ascorbate conditions are varied at different times during the culture, the extracellular matrices are altered with respect to collagen and elastin ratios. The decrease in elastin accumulation in the presence of ascorbate may be explained by an overhydroxylation of tropoelastin. Approximately 1/3 of the prolyl residues in the soluble elastin fractions isolated from cultures grown in the presence of ascorbate are hydroxylated. Since the insoluble elastin accumulated in these cultures contain the unique lysine-derived cross-links in amounts comparable to aortic tissue, this culture system proves ideal for studying the influence of extracellular matrix elastin on cell growth and metabolism.
在培养过程中，对培养的新生大鼠主动脉平滑肌细胞细胞外基质中的蛋白质组成进行了长期监测。描述了抗坏血酸对不溶性弹性蛋白和胶原蛋白的影响。在缺乏抗坏血酸的情况下，细胞积累一种不溶性弹性蛋白成分，其可占细胞外基质中总蛋白的50%。在有抗坏血酸的情况下，不溶性胶原蛋白的量增加，而不溶性弹性蛋白的含量显著减少。当在培养过程中的不同时间改变抗坏血酸条件时，细胞外基质在胶原蛋白和弹性蛋白比例方面会发生改变。抗坏血酸存在时弹性蛋白积累的减少可能是由于原弹性蛋白过度羟基化所致。从在抗坏血酸存在下生长的培养物中分离出的可溶性弹性蛋白组分中，约1/3的脯氨酰残基被羟基化。由于在这些培养物中积累的不溶性弹性蛋白含有与主动脉组织相当数量的独特赖氨酸衍生交联键，因此该培养系统被证明是研究细胞外基质弹性蛋白对细胞生长和代谢影响的理想系统。
