LOCALIZATION OF THE EPIDERMAL GROWTH-FACTOR (EGF) RECEPTOR WITHIN THE ENDOSOME OF EGF-STIMULATED EPIDERMOID CARCINOMA (A431) CELLS
LOCALIZATION OF THE EPIDERMAL GROWTH-FACTOR (EGF) RECEPTOR WITHIN THE ENDOSOME OF EGF-STIMULATED EPIDERMOID CARCINOMA (A431) CELLS
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DOI：
10.1083/jcb.102.2.500
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发表时间：
1986-02-01
影响因子：
7.8
通讯作者：
HOPKINS, CR
中科院分区：
文献类型：
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作者：
MILLER, K;BEARDMORE, J;HOPKINS, CR
我们跟踪了表皮生长因子(EGF)及其受体在人表皮样癌(A431)细胞中的内化途径。用辣根过氧化物酶标记的EGF和直接或间接偶联于胶体金的抗受体单抗(TL5和EGFR1)，我们鉴定了广泛的内体隔室，包括连接到含有小囊泡的液泡分子的管状池的外周分支网络和由连接到多囊泡体的管池网络组成的中心周室。用受体特异性抗体金对冰冻切片进行免疫细胞化学染色，结果显示在4度。在有EGF存在的情况下，受体主要分布在质膜上，少数分布在外周和中央周围小体的某些成分中。当升温到37度时。C依赖于EGF的大多数结合部位的重新分布，首先是外周内小体小室，然后是中心周围小室和溶酶体。当温度升高到20度时。C配基-受体复合体聚集在小脑中央周围区。酸性磷酸酶细胞化学仅在高尔基体的次级溶酶体和反式脑池中鉴定水解性。总之，这些观察表明，溶酶体前内体隔室延伸到中心周围复合体，并且EGF受体复合体向酸性磷酸酶阳性溶酶体的转移涉及一个不连续的、依赖于温度的步骤。
We have followed the internalization pathway of both epidermal growth factor (EGF) and its receptor in human epidermoid carcinoma (A431) cells. Using EGF conjugated with horseradish peroxidase and anti-receptor monoclonal antibodies (TL5 and EGFR1) coupled either directly or indirectly to colloidal gold we have identified an extensive elaboration of endosomal compartments, consisting of a peripheral branching network of tubular cisternae connected to vacuolar elements that contain small vesicles and a pericentriolar compartment consisting of a tubule cisternal network connected to multivesicular bodies. Immunocytochemistry on frozen thin sections using receptor-specific antibo-gold revealed that at 4.degree. C in the presence of EGF, receptors were mainly on the plasma membrane and, to a lesser extent, within some elements of both the peripheral and pericentriolar endosomal compartments. Upon warming to 37.degree. C there was an EGF-dependent redistribution of most binding sites, first to the peripheral endosome compartment and then to the pericentriolar compartment and lysosomes. Upon warming only to 20.degree. C the ligand-receptor complex accumulated in the pericentriolar compartment. Acid phosphatase cytochemistry identifies hydrolytic activity only within secondary lysosomes and trans cisternae of the Golgi stacks. Together these observations suggest that the prelysosomal endosome compartment extends to the pericentriolar complex and that the transfer of EGF receptor complexes to the acid phosphatase-positive lysosome involves a discontinuous, temperature-dependent step.