核三碘甲状腺原氨酸（T3）结合蛋白-T3复合物与染色质的结合。

Binding of nuclear triiodothyronine (T3) binding protein-T3 complex to chromatin.

作者信息

DeGroot L J, Hill L, Rue P

出版信息

Endocrinology. 1976 Dec;99(6):1605-11. doi: 10.1210/endo-99-6-1605.

PMID:11991

Abstract

Nuclear tirrodothyronine (T3) binding protein (NTBP)-T3 complex, prepared from liver nuclei of rats given [125I]T3 in vovo, rebinds to rat nuclear chromatin at pH 7.4 and at low, but not high, KCl concentrations. Liver NTBP-T3 complex binds to chromatin from liver, kidney, heart, brain, testis, and spleen. Binding was depressed at pH8, by addition of 10 mm CaCl2 or 100 mM MgCl2, and by 1 mM GTP or UTP. Although heart chromatin bound the most NTBP-T3 complex and brain the least, there is no clear separation of binding activity on comparison of three T3-responsive tissues (heart, liver, kidney) to the T3 insensitive tissues. Under the conditions of these experiments, there was no evident competition for binding sites on any of the six chromatins tested.

摘要

从经体内给予[125I]T3的大鼠肝细胞核制备的核甲状腺素（T3）结合蛋白（NTBP）-T3复合物，在pH 7.4及低KCl浓度（而非高KCl浓度）下可重新结合至大鼠核染色质。肝脏NTBP-T3复合物可与来自肝脏、肾脏、心脏、大脑、睾丸和脾脏的染色质结合。在pH 8时，通过添加10 mM CaCl2或100 mM MgCl2，以及1 mM GTP或UTP，结合作用受到抑制。尽管心脏染色质结合的NTBP-T3复合物最多，而大脑最少，但在比较三种T3反应性组织（心脏、肝脏、肾脏）与T3不敏感组织时，结合活性并无明显差异。在这些实验条件下，在所测试的六种染色质中，均未观察到对结合位点的明显竞争。