Apotransferrin stimulation of thyroid hormone dependent rat pituitary tumor cell growth in serum-free chemically defined medium: role of FE(III) chelation.
Apotransferrin stimulation of thyroid hormone dependent rat pituitary tumor cell growth in serum-free chemically defined medium: role of FE(III) chelation.
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脱铁转铁蛋白刺激甲状腺激素依赖性大鼠垂体肿瘤细胞在无血清化学成分确定的培养基中生长：FE(III) 螯合的作用。
DOI：
10.1002/jcp.1041560319
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发表时间：
1993
影响因子：
5.6
通讯作者：
Sirbasku,DA
中科院分区：
文献类型：
--
作者：
Eby,JE;Sato,H;Sirbasku,DA
在无血清限定培养物中，GH 1 大鼠垂体肿瘤细胞的三碘甲状腺原氨酸 (T 3) 依赖性生长需要脱铁转铁蛋白 (apo Tf)（Sirbasku 等人：Mol. Cell. Endocrinol., 77: C47–C55, 1991）。二铁转铁蛋白 (2Fe·Tf) 作为铁源也是必需的（Eby 等人：Anal. Biochem., 203: 317–325, 1992）。此外，通过向培养基中添加可溶性 Fe (III) 可防止 T 3 依赖性（Sato 等人：In Vitro Cell. Dev. Biol., 27A: 599–602, 1991）。虽然我们的数据表明 apo Tf 通过 Fe (III) 螯合引起生长，但仍需要直接证据。我们使用尿素聚丙烯酰胺凝胶电泳以及放射自显影和蛋白质免疫印迹来测量生长的 GH 1 细胞培养物中的 Fe (III) 含量，并鉴定存在的 apo Tf、单金属转铁蛋白和 2Fe·Tf。我们发现 apo Tf 本身并不引起生长，而是螯合 Fe (III) 的抑制水平。事实上，只要 Fe (III) 还原至≤ 0.6 μM，apo Tf 根本不需要存在。此外，其他蛋白质和非蛋白质 Fe (III) 螯合剂也被证明与 apo Tf 一样有效。在这里，我们报告垂体细胞被 ≥ 1.2 μM Fe (III) 完全抑制，这是许多培养基中可能预期的浓度，通常不认为会影响生长。垂体细胞对 Fe (III) 的高度敏感性表明需要进一步研究以确定哪些细胞功能受到影响以及它们如何干扰甲状腺激素依赖。© 1993 Wiley-Liss, Inc.
Triiodothyronine (T 3) dependent growth of GH 1 rat pituitary tumor cells in serum-free defined culture requires apotransferrin (apo Tf)(Sirbasku et al.: Mol. Cell. Endocrinol., 77: C47–C55, 1991). Diferric transferrin (2Fe· Tf) also is necessary as an iron source (Eby et al.: Anal. Biochem., 203: 317–325, 1992). Further, T 3 dependence is prevented by soluble Fe (III) addition to the medium (Sato et al.: In Vitro Cell. Dev. Biol., 27A: 599–602, 1991). While our data suggested that apo Tf caused growth by chelation of Fe (III), direct evidence was required. We used urea polyacrylamide gel electrophoresis along with autoradiography and Western immunoblotting to measure the Fe (III) content of growing GH 1 cell cultures and identify the apo Tf, mono-metal transferrins and 2Fe· Tf present. We found that apo Tf per se did not cause growth but instead chelated inhibitory levels of Fe (III). In fact, apo Tf need not be present at all provided that Fe (III) is reduced to≤ 0.6 μM. In addition, other protein and non-protein Fe (III) chelators were shown to be as effective as apo Tf. Here, we report that pituitary cells are completely inhibited by≥ 1.2 μM Fe (III), which are concentrations which might be expected in many culture media and usually are not thought to influence growth. The high sensitivity of pituitary cells to Fe (III) suggests further study to determine what cellular functions are affected and how they interfere with thyroid hormone dependence.© 1993 Wiley-Liss, Inc.