Insulin capture by an insulin-linked polymorphic region G-quadruplex DNA oligonucleotide
Insulin capture by an insulin-linked polymorphic region G-quadruplex DNA oligonucleotide
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DOI：
10.1021/ja056097c
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发表时间：
2006-04-19
影响因子：
15
通讯作者：
McGown, LB
中科院分区：
文献类型：
--
作者：
Connor, AC;Frederick, KA;McGown, LB
本文报道了一种含有人胰岛素基因启动子区的胰岛素连接多态性区（ILPR）的两个重复序列的G-四链体DNA寡核苷酸对胰岛素的捕获。利用亲和MALDI质谱和亲和毛细管色谱，证明了固定化微球以高选择性从标准溶液和胰腺细胞核提取物中捕获人胰岛素。胰岛素优先捕获的两个重复的ILPR颗粒超过另一个G-四链体形成的颗粒，凝血酶结合适体，以及超过一个单一的重复的ILPR序列，是不能形成的G-四链体架构。结合显示涉及胰岛素的β链。这一发现提出了胰岛素可能与体内ILPR中形成的G-四链体DNA结合，从而在调节胰岛素基因表达中发挥作用的可能性，并且为设计胰岛素类似物以探索这一假设提供了基础。人胰岛素的DNA配体的可用性也具有分析重要性，为胰岛素的体外或体内检测和传感以及从生物样品中分离和纯化提供了抗体的替代方案。
Insulin capture by a G-quadruplex DNA oligonucleotide containing a two-repeat sequence of the insulin-linked polymorphic region (ILPR) of the human insulin gene promoter region is reported. The immobilized oligonucleoticle was demonstrated to capture human insulin from standard solutions and from nuclear extracts of pancreatic cells with high selectivity, using affinity MALDI mass spectrometry and affinity capillary chromatography. Insulin was preferentially captured by the two-repeat ILPR oligonucleoticle over another G-quadruplex-forming oligonucleoticle, the thrombin-binding aptamer, as well as over a single repeat of the ILPR sequence that is not capable of forming the G-quadruplex architecture. Binding was shown to involve the beta chain of insulin. The discovery raises the possibility that insulin may bind to G-quadruplex DNA formed in the ILPR in vivo and thereby play a role in modulation of insulin gene expression, and it provides a basis for design of insulin analogues to probe this hypothesis. The availability of a DNA ligand to human insulin has analytical importance as well, offering an alternative to antibodies for in vitro or in vivo detection and sensing of insulin as well as its isolation and purification from biological samples.