Skinner M K, Griswold M D
J Biol Chem. 1980 Oct 25;255(20):9523-5.
One of the major proteins secreted by Sertoli cells (Band 3) has a molecular weight on sodium dodecyl sulfate-polyacrylamide gels which corresponds to rat serum transferrin. The preparation of Sertoli cell-secreted proteins contains an iron-binding protein with electrophoretic properties on native polyacrylamide gels similar to serum transferrin. Antibodies against Sertoli cell-secreted proteins contain a component which will immunoprecipitate serum transferrin. Antibodies to serum transferrin cross-react with and immunoprecipitate a major component (Band 3) of [35S]-methionine-labeled Sertoli cell-secreted proteins. We propose that testicular transferrin is a major secretory product of Sertoli cells in culture. In addition to transferrin, antiserum to rat serum proteins will immunoprecipitate one other polypeptide from preparations of Sertoli cell-secreted proteins.
支持细胞分泌的一种主要蛋白质（条带3）在十二烷基硫酸钠-聚丙烯酰胺凝胶上的分子量与大鼠血清转铁蛋白相对应。支持细胞分泌蛋白的制备物中含有一种铁结合蛋白，其在天然聚丙烯酰胺凝胶上的电泳特性与血清转铁蛋白相似。抗支持细胞分泌蛋白的抗体含有一种能免疫沉淀血清转铁蛋白的成分。抗血清转铁蛋白抗体与[35S]-甲硫氨酸标记的支持细胞分泌蛋白的一种主要成分（条带3）发生交叉反应并免疫沉淀该成分。我们提出，睾丸转铁蛋白是培养的支持细胞的一种主要分泌产物。除转铁蛋白外，大鼠血清蛋白抗血清还能从支持细胞分泌蛋白的制备物中免疫沉淀出另一种多肽。
