Mapping the binding sites of human erythrocyte ankyrin for the anion exchanger and spectrin.
Mapping the binding sites of human erythrocyte ankyrin for the anion exchanger and spectrin.
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DOI：
10.1016/s0021-9258(18)86987-3
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发表时间：
1990-06
期刊：
影响因子：
--
通讯作者：
L. Davis;V. Bennett
中科院分区：
文献类型：
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作者：
L. Davis;V. Bennett
本报告描述了初步表征的结合位点的锚蛋白的血影蛋白和阴离子交换剂使用定义的亚片段分离纯化的锚蛋白域。锚蛋白的血影蛋白结合结构域由两个亚结构域组成：一个酸性的富含脯氨酸的区域（pI = 4），涉及氨基末端80个残基，从828到908，和一个碱性区域（pI = 8.8），从898延伸到1386。血影蛋白结合结构域的氨基末端70个氨基酸对于与血影蛋白的结合是至关重要的，因为缺失该区域的亚片段在取代血影蛋白与由内而外的膜囊泡的结合中的活性仅为完整结构域的5%，而缺失酸性结构域的前38个残基导致活性降低10倍。阴离子交换剂结合位点被限制在一个89 kDa的结构域，该结构域被分离并表征为具有约30% α-螺旋构型的球状分子。从残基403延伸至779（或可能740）的89-kDa结构域的亚片段保留与阴离子交换剂缔合的能力。89-kDa结构域由从残基35延伸至778的一系列33个氨基酸的串联重复序列组成（Lux，S.，约翰，K.，和班尼特，V.（1990）自然344，36-42）。残基403-779的活性表明89-kDa结构域的33个氨基酸重复序列负责锚蛋白和阴离子交换剂之间的缔合。锚蛋白的33个氨基酸的重复序列代表了一个古老的基序，也发现在果蝇，酵母和秀丽隐杆线虫的蛋白质。33个氨基酸的重复序列参与与阴离子交换剂的相互作用，这一发现意味着该基序可能在不同蛋白质的分子识别中发挥作用。
This report describes initial characterization of the binding sites of ankyrin for spectrin and the anion exchanger using defined subfragments isolated from purified ankyrin domains. The spectrin-binding domain of ankyrin is comprised of two subdomains: an acidic, proline-rich region (pI = 4) involving the amino-terminal 80 residues from 828 to 908 and a basic region (pI = 8.8) that extends from 898 to 1386. The amino-terminal 70 amino acids of the spectrin-binding domain are critical for association with spectrin, since a subfragment missing this region is only 5% as active as the intact domain in displacing binding of spectrin to inside-out membrane vesicles, while deletion of the first 38 residues of the acidic domain results in a 10-fold reduction in activity. The anion exchanger-binding site is confined to an 89-kDa domain that was isolated and characterized as a globular molecule with approximately 30% alpha-helical configuration. A subfragment of the 89-kDa domain extending from residues 403 to 779 (or possibly 740) retains ability to associate with the anion exchanger. The 89-kDa domain is comprised of a series of tandem repeats of 33 amino acids that extend from residues 35 to 778 (Lux, S., John, K., and Bennett, V. (1990) Nature 344, 36-42). The activity of residues 403-779 demonstrates that the 33-amino acid repeats of the 89-kDa domain are responsible for association between ankyrin and the anion exchanger. The 33-amino acid repeating sequence of ankyrin represents an ancient motif also found in proteins of Drosophila, yeast, and Caenor habditis elegans. The finding that the 33-amino acid repeating sequence is involved in interaction with the anion exchanger implies that this motif may perform a role in molecular recognition in diverse proteins.