期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1983
卷号：80
期号：2
页码：388-392
DOI：10.1073/pnas.80.2.388
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Procollagen and partially processed procollagen from cultures of primary chicken embryo tendon cells appeared as segment-long-spacing (SLS)-like aggregates when drops of medium were negatively stained and examined by electron microscopy. Similar aggregates were obtained after negative staining of medium partially purified by gel filtration and also after staining thin sections of fixed, dehydrated, and embedded pellets formed by prolonged ultracentrifugation of whole culture medium. In contrast to results from electron microscopy, analysis by velocity density gradient sedimentation or sedimentation equilibrium indicated the exclusive presence of procollagen or partially processed procollagen monomers in solution. These contradictory data can be reconciled if procollagen exists in monomeric form when greatly diluted (as in culture medium), and in specific aggregated form (SLS) at high concentration. We believe that cells in vivo secrete procollagen in high, local concentration packaged in the SLS form. We propose that such zero-D arrayed packages are the precursors of native collagen fibrils.
