A group of scientists from Xi’an, China have created a new system for analyzing cell membranes based around haloalkane dehalogenase protein tag (HALO)-tag technology. Their research was published in Talanta (1).
Cell membrane and biology, biological concept, 3d rendering. | Image Credit: © Vink Fan - stock.adobe.com
Cell membrane chromatography (CMC) is effective for studying receptors with multiple transmembrane structures, such as MAS-related G protein-coupled receptor X2 (MrgX2). For CMC to function properly, maintenance must be kept for the complete biological structure of a membrane receptor. However, to obtain more convenient and stable CMC models, this system must be further improved.
For this study, the scientists used HALO-tag technology to create a new MrgX2/CMC model. The fusion receptors of this process were expressed in HEK293 cells, with silica gel being modified for the rapid capture of fusion receptors. This was done via one-step acylation using a substrate of HALO-tag (chloroalkanes). According to the scientists, their new CMC model (MrgX2-HALO-tag/CMC model) was quicker to prepare, more stable, and had a longer lifespan than previous MrgX2-SNAP-tag/CMC models.
Combined with a high-performance liquid chromatograph-tandem mass spectrometry (HPLC–MS/MS) system, the new model was used to identify bioactive components in traditional Chinese medicine. Sanggenon C and morusin were identified as anti-pseudo-allergic components. The MrgX2-HALO-tag/CMC model was also used to analyze ligand-receptor interaction. According to the system, the affinity order of four discovered ligands was desipramine < imipramine < amitriptyline < clomipramine. When compared to the results obtained using the MrgX2-HALO-tag/CMC model alone, the results proved consistent. Overall, the scientists remained optimistic about their new system, stating, “The MrgX2-HALO-tag/CMC model provides ideas and application prospects for the immobilization of cell membrane that contains receptors with more transmembrane structures” (1).
(1) Jia, Q.; Lv, Y.; Miao, C.; Feng, J.; Ding, Y.; Zhou, T.; Han, S.; He, L. A New MAS-Related G Protein-Coupled Receptor X2 Cell Membrane Chromatography Analysis Model Based on HALO-Tag Technology and Its Applications. Talanta 2023, 268 (1), 125317. DOI: https://doi.org/10.1016/j.talanta.2023.125317
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