首页    期刊浏览 2024年11月30日 星期六
登录注册

文章基本信息

  • 标题:Precursors of Collagen Secreted by Cultured Human Fibroblasts
  • 本地全文:下载
  • 作者:Burton Goldberg ; Ervin H. Epstein ; Charles J. Sherr
  • 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:1972
  • 卷号:69
  • 期号:12
  • 页码:3655-3659
  • DOI:10.1073/pnas.69.12.3655
  • 语种:English
  • 出版社:The National Academy of Sciences of the United States of America
  • 摘要:Soluble precursors of collagen ("procollagens") in the culture medium of human diploid fibroblasts were characterized by molecular sieve chromatography on 6% agarose and by sodium dodecyl sulfate-acrylamide gel electrophoresis. Under the denaturing conditions for gels, the following molecular species were identified: a major species of three procollagen chains, a procollagen dimer, and free procollagen chains. Reduction with 2-mercaptoethanol completely dissociated the trimer and dimer, releasing procollagen [α]1 and procollagen [α]2 chains with molecular weights of about 120,000. Both pro [α]1 and pro [α]2 chains could be labeled with [35S]cystine. In addition, free procollagen chains with molecular weights of less than 120,000, but heavier than native [α] chains, were identified in gels. Radioactivity in all of the above molecules could be chased into native [α] chains extracted from extracellular fibers of the cell layers. The data indicate that: (i) collagen is secreted as a disulfidestabilized procollagen trimer with the composition, (pro [α]1)2{middle dot}pro [α]2; (ii) noncovalent interactions maintain the three-chain assembly during stepwise enzymatic excisions of N-terminal, cysteine-containing procellagen peptides; and (iii) after such excisions, native helical molecules, ([α]1)2{middle dot}[α]2, precipitate as fibers in the cell layers.
  • 关键词:isotopic labeling ; chromatography ; gel electrophoresis
国家哲学社会科学文献中心版权所有