Wanker E E, Rovira C, Scherzinger E, Hasenbank R, Wälter S, Tait D, Colicelli J, Lehrach H
Max Planck Institut für Molekulare Genetik, Berlin (Dahlem), Germany.
Hum Mol Genet. 1997 Mar;6(3):487-95. doi: 10.1093/hmg/6.3.487.
We report the discovery of the huntingtin interacting protein I (HIP-I) which binds specifically to the N-terminus of human huntingtin, both in the two-hybrid screen and in in vitro binding experiments. For the interaction in vivo, a protein region downstream of the polyglutamine stretch in huntingtin is essential. The HIP1 cDNA isolated by the two-hybrid screen encodes a 55 kDa fragment of a novel protein. Using an affinity-purified polyclonal antibody raised against recombinant HIP-I, a protein of 116 kDa was detected in brain extracts by Western blot analysis. The predicted amino acid sequence of the HIP-I fragment exhibits significant similarity to cytoskeleton proteins, suggesting that HIP-I and huntingtin play a functional role in the cell filament networks. The HIP1 gene is ubiquitously expressed in different brain regions at low level. HIP-I is enriched in human brain but can also be detected in other human tissues as well as in mouse brain. HIP-I and huntingtin behave almost identically during subcellular fractionation and both proteins are enriched in the membrane containing fractions.
我们报告了亨廷顿相互作用蛋白I（HIP-I）的发现，该蛋白在双杂交筛选和体外结合实验中均能特异性结合人亨廷顿蛋白的N端。对于体内相互作用，亨廷顿蛋白中多聚谷氨酰胺延伸下游的一个蛋白区域至关重要。通过双杂交筛选分离出的HIP1 cDNA编码一种新型蛋白的55 kDa片段。使用针对重组HIP-I制备的亲和纯化多克隆抗体，通过蛋白质印迹分析在脑提取物中检测到一种116 kDa的蛋白。HIP-I片段的预测氨基酸序列与细胞骨架蛋白具有显著相似性，这表明HIP-I和亨廷顿蛋白在细胞丝状网络中发挥功能作用。HIP1基因在不同脑区低水平普遍表达。HIP-I在人脑中含量丰富，但在其他人体组织以及小鼠脑中也能检测到。在亚细胞分级分离过程中，HIP-I和亨廷顿蛋白的行为几乎相同，两种蛋白在含膜组分中均有富集。
