LACTOFERRIN BINDING-SITES AND NUCLEAR-LOCALIZATION IN K562(S) CELLS
LACTOFERRIN BINDING-SITES AND NUCLEAR-LOCALIZATION IN K562(S) CELLS
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DOI：
10.1002/jcp.1041530306
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发表时间：
1992-12-01
影响因子：
5.6
通讯作者：
RAVAZZOLO, R
中科院分区：
文献类型：
--
作者：
GARRE, C;BIANCHISCARRA, G;RAVAZZOLO, R
乳铁蛋白是一种单链阳离子糖蛋白，存在于中性粒细胞的次级颗粒中，作为骨髓生成的负反馈调节剂。在不同造血细胞类型的表面上检测到乳铁蛋白的特异性受体。已经报道了乳铁蛋白对培养物中细胞生长的影响。本文证实了K562细胞上存在乳铁蛋白特异性结合位点，并估算了结合位点的数目和解离常数。通过对K562裂解物进行蛋白质印迹分析，我们发现约120 kDa的条带负责乳铁蛋白的特异性结合。我们还表明，乳铁蛋白，在细胞表面结合后，在一个温度依赖性的方式内化，是作为一个DNA连接的蛋白质在核提取物中的免疫检测。
Lactoferrin, a single chain cationic glycoprotein, present in the secondary granules of neutrophils, acts as a negative feedback regulator of myelopoiesis. Specific receptors for lactoferrin were, detected on the surface of different hematopoietic cell types. The influence of lactoferrin on cell growth in culture has been reported. Interactions of lactoferrin with DNA were also demonstrated.In the present paper we confirm the presence of lactoferrin specific binding sites on K562 cells and we estimate the number of binding sites and the dissociation constant. By Western blotting analysis performed on K562 lysates we find a band of about 120 kDa responsible for specific binding of lactoferrin. We also show that lactoferrin, after binding at the cell surface, is internalized in a temperature dependent way and is immunologically detectable as a DNA-linked protein in nuclear extracts.