Parkinson J, Kadler K E, Brass A
School of Biological Sciences, University of Manchester, UK.
J Mol Biol. 1995 Apr 7;247(4):823-31. doi: 10.1006/jmbi.1994.0182.
Type I collagen is a rod-like protein which self-assembles in a regular array to form elongated fibrils. The process of fibril formation, termed fibrillogenesis, is driven by the increase in entropy associated with loss of water from the bound monomers. A model based on diffusion limited aggregation (DLA) was used to investigate some of the mechanisms involved in this process. The aggregates created in the model displayed several features in common with collagen fibrils including an elongated morphology and a preference for tip growth. Analysis of these aggregates revealed a linear relationship between mass and distance from the tip, consistent with experimental observations. Intrafibrillar fluidity was introduced into the model by using a surface diffusion term. This led to the formation of aggregates with more compact morphologies. These results strongly implicate the role of diffusion limited growth in collagen fibril formation.
I型胶原蛋白是一种棒状蛋白质，它以规则的阵列形式自组装形成细长的纤维。纤维形成的过程，称为原纤维形成，是由与结合单体失去水分相关的熵增加所驱动的。基于扩散限制聚集（DLA）的模型被用于研究这个过程中涉及的一些机制。模型中产生的聚集体表现出与胶原纤维的几个共同特征，包括细长的形态和对尖端生长的偏好。对这些聚集体的分析揭示了质量与距尖端距离之间的线性关系，这与实验观察结果一致。通过使用表面扩散项将纤维内流动性引入模型。这导致形成形态更紧凑的聚集体。这些结果有力地表明了扩散限制生长在胶原纤维形成中的作用。
