Gerstenfeld L, Beldekas J C, Sonenshein G E, Franzblau C
J Biol Chem. 1984 Jul 25;259(14):9158-62.
The processing of type III and type I procollagen molecules in cultured bovine aortic smooth muscle cells was investigated. The molecular identities of the processing intermediates of type III and type I procollagen were characterized by analysis of the radioactive collagenous components using mammalian collagenase and pepsin digestions and cyanogen bromide peptide mapping. The results indicate that the processed intermediates for procollagen type III and type I are their respective pC components. Although the processing pathways for both collagen types are the same, data from pulse-chase experiments suggest that the rates at which the processing occurs are different. Type I procollagen is processed more rapidly to its intermediate than is type III procollagen. The type I pC intermediate is almost completely processed to alpha-chains and a significant portion of these fully processed molecules remains in a soluble form even after 11 h. In the same time period, the type III pC intermediate is slowly converted to alpha-chains. Since beta-aminopropionitrile was not employed in these studies, significant accumulation of collagen chains into the insoluble extracellular matrix was observed during the chase period.
研究了培养的牛主动脉平滑肌细胞中III型和I型前胶原分子的加工过程。通过使用哺乳动物胶原酶和胃蛋白酶消化以及溴化氰肽图谱分析放射性胶原成分，对III型和I型前胶原加工中间体的分子特性进行了表征。结果表明，III型和I型前胶原的加工中间体分别是它们各自的pC成分。虽然两种胶原类型的加工途径相同，但脉冲追踪实验的数据表明加工发生的速率不同。I型前胶原比III型前胶原更快地加工成其中间体。I型pC中间体几乎完全加工成α链，即使在11小时后，这些完全加工的分子中有很大一部分仍以可溶形式存在。在同一时间段内，III型pC中间体缓慢转化为α链。由于这些研究中未使用β-氨基丙腈，在追踪期内观察到胶原链大量积累到不溶性细胞外基质中。
