Goldstein B, Wofsy C
Cell Biophys. 1981 Sep;3(3):251-77. doi: 10.1007/BF02782627.
The recycling to the cell surface of previously internalized coated pits has been proposed as a likely mechanism for the rapid regeneration of coated pits on human fibroblast surfaces at 37 degrees C (1). We present a general mathematical model of coated pit recycling for the case when the coat cycles as a single unit, and use it to analyze certain time and temperature dependent data obtained by Anderson et al. (1) and Vermeer et al. (2). We show how recycling can account for these data and how this type of data can be used to distinguish between different possible recycling mechanisms. We show that these data are inconsistent with a two compartment model where coat material simply shuttles back and forth between coated pits and short-lived coated vesicles. From these data we estimate for human fibroblasts at 37 degrees C: that the time for a coated pit to be replenished through recycling after it is lost through internalization is greater than 3.5 min; and that at any moment 53% or less of the cell's clathrin that is involved in coated pit recycling is on the cell surface.
将先前内化的包被小窝回收至细胞表面，这被认为是37摄氏度时人成纤维细胞表面包被小窝快速再生的一种可能机制(1)。我们针对包被以单个单元循环的情况，提出了一个包被小窝回收的通用数学模型，并用它来分析Anderson等人(1)以及Vermeer等人(2)获得的某些与时间和温度相关的数据。我们展示了回收如何解释这些数据，以及如何利用这类数据来区分不同的可能回收机制。我们表明，这些数据与一个两室模型不一致，在该模型中，包被材料只是在包被小窝和短命的包被小泡之间来回穿梭。根据这些数据，我们估算出在37摄氏度时人成纤维细胞的情况如下：一个包被小窝通过内化丢失后，通过回收进行补充所需的时间大于3.5分钟；并且在任何时刻，参与包被小窝回收的细胞网格蛋白中，有53%或更少位于细胞表面。
