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：1
页码：480-484
DOI：10.1073/pnas.77.1.480
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Colchicine (2 microM) did not affect the initial rate of association of 125I-labeled epidermal growth factor (125I-EGF) to Swiss 3T3 cells but continued incubation (up to 24 hr) led to an increase in cell-associated radioactivity. The effect is also produced by Colcemid, vinblastine, and podophyllotoxin but not by lumicolchicine. Disruption of microtubules with colchicine does not alter the rate of "down regulation" of EGF receptors, suggesting the binding and internalization of the factor proceed unchanged. However, colchicine markedly decreases the rate of appearance of acid-soluble radioactivity from cells either incubated continuously with 125I-EGF for 24 hr or exposed to the radioactive peptide for only 1 or 3 hr. The results indicate that colchicine decreases the rate of degradation of internalized 125I-EGF. Because antitubulin agents enhance the mitogenic effect of EGF our results suggest that peptide degradation can be dissociated from the long-term biological effect.
