Expression, characterization and ligand specificity of lipocalin-1 interacting membrane receptor (LIMR)
Expression, characterization and ligand specificity of lipocalin-1 interacting membrane receptor (LIMR)
复制标题
DOI：
10.3109/09687688.2013.823018
复制
发表时间：
2013-08-01
影响因子：
--
通讯作者：
Findlay, John B. C.
中科院分区：
文献类型：
--
作者：
Hesselink, Renske W.;Findlay, John B. C.
人脂质运载蛋白-1相互作用膜受体（LMR）是第一个被鉴定的脂质运载蛋白受体，作为脂质运载蛋白-1（Lcn 1）的特异性受体。随后，据报道LMR也与其他配体相互作用，特别是与牛脂质运载蛋白β-乳球蛋白（BLG）和与无关的分泌球蛋白子宫球蛋白（UG）相互作用。为了更详细地研究这种原型脂质运载蛋白受体的配体结合行为，开发了用于在果蝇Schneider 2（S2）细胞中重组表达LMR的系统，以及用于随后的蛋白质的溶解和纯化。当溶解在正十二烷基β-D-麦芽糖苷（DDM）中时，受体形成二聚体或更大的寡聚体。通过α-V5抗体将全长功能性受体捕获到表面等离子体共振（SPR）芯片上，并及时跟踪各种潜在配体的结合。以这种方式，LMR显示出对Lcn 1具有高度特异性，以低微摩尔至高纳摩尔亲和力结合脂质运载蛋白。没有与任何其他推定的配体的相互作用可以检测到，引起怀疑的生理相关性的报告结合BLG和UG的受体。
Human lipocalin-1 interacting membrane receptor (LIMR) was the first lipocalin receptor to be identified, as a specific receptor for lipocalin-1 (Lcn1). Subsequently LIMR has been reported to interact with other ligands as well, notably with the bovine lipocalin beta-lactoglobulin (BLG) and with the unrelated secretoglobin uteroglobin (UG). To study the ligand-binding behaviour of this prototypic lipocalin receptor in more detail, a system was developed for the recombinant expression of LIMR in Drosophila Schneider 2 (S2) cells, and for the subsequent solubilization and purification of the protein. The receptor forms dimers or larger oligomers when solubilized in n-dodecyl beta-D-maltoside (DDM). The full-length, functional receptor was captured onto a surface plasmon resonance (SPR) chip via an alpha-V5 antibody, and the binding of various potential ligands was followed in time. In this way, LIMR was shown to be highly specific for Lcn1, binding the lipocalin with low micromolar to high nanomolar affinity. No interactions with any of the other putative ligands could be detected, raising doubts about the physiological relevance of the reported binding of BLG and UG to the receptor.