Recognition of RANTES by extracellular parts of the CCR5 receptor
Recognition of RANTES by extracellular parts of the CCR5 receptor
复制标题
DOI：
10.1016/j.jmb.2006.10.040
复制
发表时间：
2007-01-26
影响因子：
5.6
通讯作者：
Grzesiek, Stephan
中科院分区：
文献类型：
--
作者：
Duma, Luminita;Haeussinger, Daniel;Grzesiek, Stephan
趋化因子 RANTES（受激活、正常 T 细胞表达和分泌的调节）是 CCR5 的天然配体，CCR5 是主要的 HIV-1 辅助受体之一。它作为人类免疫缺陷病毒 1 (HIV-1) 免疫反应的一部分而分泌，并抑制 CCR5 依赖性 (R5) HIV-1 分离株的感染。我们通过水溶液中的异核核磁共振波谱研究了 RANTES 与源自 CCR5 胞外结构域的几种肽的相互作用。我们发现，包含 CCR5 N 端结构域前 25 个氨基酸残基并在 Y10 和 Y14 侧链硫酸化的肽仅以微摩尔亲和力与单体形式的 RANTES 结合。与硫酸化肽的紧密结合相反，非硫酸化形式的相同肽的亲和力降低了两个数量级以上。源自 CCR5 胞外环 ECL1、ECL2 和 ECL3 的肽仅显示出非常中等且大部分为非特异性结合。硫酸化 N 末端肽相互作用的化学位移图揭示了 RANTES 上的连续结合表面，其包含第一条 β 链、N 环、第四条链的氨基酸残基以及残基 30 和 40 周围的转角。该结合表面与二聚体界面大部分重叠，并且带强正电荷，为单体与肽的排他性结合以及 Y10 和 Y14 侧链上的负硫酸基团的需求提供了理论依据。结合表面也很大程度上与之前通过肽扫描和诱变研究确定的对 HIV 阻断至关重要的片段重叠。这些数据为 RANTES-CCR5 相互作用的结构-功能关系提供了新的见解，可能有助于设计新型 HIV-1 抑制剂。 (c) 2006 Elsevier Ltd. 保留所有权利。
The chemokine RANTES (regulated upon activation, normal T-cell expressed and secreted) is a natural ligand of CCR5, one of the major HIV-1 coreceptors. It is secreted as part of the immune response to human immunodeficiency virus 1 (HIV-1) and inhibits infection by CCR5-dependent (R5) HIV-1 isolates. We have investigated the interaction of RANTES with several peptides derived from the extracellular domains of CCR5 by heteronuclear NMR spectroscopy in aqueous solution. We show that a peptide comprising the first 25 amino acid residues of the CCR5 N-terminal domain and sulfated at the Y10 and Y14 side-chains binds with micromolar affinity exclusively to the monomeric form of RANTES. In contrast to the tight binding of the sulfated peptide, the affinity of the same peptide in non-sulfated form was reduced by more than two orders of magnitude. Peptides derived from the CCR5 extracellular loops ECL1, ECL2 and ECL3 showed only very moderate and mostly non-specific binding. Chemical shift mapping of the interaction of the sulfated Nterminal peptide reveals a contiguous binding surface on RANTES, which comprises amino acid residues of the first beta-strand, the N-loop, the fourth strand and the turns around residues 30 and 40. This binding surface largely overlaps with the dimer interface and is strongly positively charged, providing a rationale for the exclusive binding of the monomer to the peptide and the requirement of the negative sulfate groups at the Y10 and Y14 side-chains. The binding surface also largely overlaps with the segments that were identified previously as crucial for HIV blockade by peptide scanning and mutagenesis studies. These data offer new insights into the structure-function relation of the RANTES-CCR5 interaction and may be helpful for the design of novel HIV-1 inhibitors. (c) 2006 Elsevier Ltd. All rights reserved.