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：1980
卷号：77
期号：8
页码：4657-4661
DOI：10.1073/pnas.77.8.4657
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Insect cells of an established line, Drosophila Kc cells, take up and metabolize juvenile hormone (JH). The cytoplasm of these cells contains a protein that binds JH with specificity, saturability, and high affinity (Kd = 1.56 x 10-8 M). The kinetics for the specific binding and dissociation of JH I were independently measured, and the rate constants were found to be ka = 1.3 x 106 M-1 min-1, kd = 1.3 x 10-2 min-1, respectively. All three juvenile hormones bind to the protein with comparable affinities; the corresponding acid or diol metabolites of JH I are not bound. About 2500 hormone-binding protein molecules are present per cell. The protein has a molecular weight of 80,000 as estimated by gel permeation chromatography and by sucrose gradient sedimentation. The properties of this protein suggest that it functions as a cytoplasmic receptor for juvenile hormone.
