Tryggvason K, Pihlajaniemi T, Salo T
Ciba Found Symp. 1984;108:117-29. doi: 10.1002/9780470720899.ch8.
The effects of trypsin on soluble type IV procollagen from the EHS mouse tumour were studied. The enzyme cleaved the pro alpha 1(IV) and pro alpha 2(IV) chains, causing only a minor decrease in the molecular weight of the pro alpha 1(IV) chain, whereas the pro alpha 2(IV) chain was degraded to at least two smaller peptides. Analyses of the uncleaved and trypsin-digested type IV procollagen by molecular sieving, with and without reduction and denaturation, were consistent with the two chains, pro alpha 1(IV) and pro alpha 2(IV), being in the same molecule, as a heterotrimer with the composition [pro alpha 1(IV)]2pro alpha 2(IV). It was also shown that the tumour promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) induces the secretion of a type IV collagen-degrading metal protease into media of cultured human skin fibroblasts. This result supports previously reported findings that such an enzyme is associated with malignant transformation of cells.
研究了胰蛋白酶对EHS小鼠肿瘤中可溶性IV型前胶原的作用。该酶切割了前α1(IV)链和前α2(IV)链，导致前α1(IV)链的分子量仅略有下降，而前α2(IV)链则降解为至少两种较小的肽。通过分子筛分对未切割和经胰蛋白酶消化的IV型前胶原进行分析，无论是否进行还原和变性，结果均表明前α1(IV)链和前α2(IV)链存在于同一分子中，形成了组成成分为[前α1(IV)]2前α2(IV)的异源三聚体。研究还表明，肿瘤启动子12-O-十四酰佛波醇-13-乙酸酯（TPA）可诱导一种IV型胶原降解金属蛋白酶分泌到培养的人皮肤成纤维细胞培养基中。这一结果支持了先前报道的此类酶与细胞恶性转化有关的发现。
