缓激肽受体是G蛋白偶联受体家族的重要成员之一,它所介导的信号转导对于维持机体内心血管系统动态平衡和炎症方面发挥了重要的作用。近年来,随着荧光共振能量转移(fluorescence resonance energy transfer,FRET)和生物发光共振能量转移(...缓激肽受体是G蛋白偶联受体家族的重要成员之一,它所介导的信号转导对于维持机体内心血管系统动态平衡和炎症方面发挥了重要的作用。近年来,随着荧光共振能量转移(fluorescence resonance energy transfer,FRET)和生物发光共振能量转移(bioluminescence resonance energy trans-fer,BRET)等技术的相继出现,发现缓激肽受体不仅以单体形式存在,还可能以二聚体甚至是高阶寡聚体的形式参与细胞内的病理生理过程。与单体相比,二聚体(或高阶寡聚体)的信号转导和病理功能都产生了相应变化。本文就缓激肽受体及其二聚体所介导的信号途径、生理病理过程及新的研究技术做一简要综述。展开更多
Syndecan-3 (N-syndecan) is a transmembrane heparan sulfate proteoglycan abundantly expressed in developing brain. In addition to acting as a coreceptor, syndecan-3 acts as a signaling receptor upon binding of its liga...Syndecan-3 (N-syndecan) is a transmembrane heparan sulfate proteoglycan abundantly expressed in developing brain. In addition to acting as a coreceptor, syndecan-3 acts as a signaling receptor upon binding of its ligand HB-GAM (heparin-binding growth-associated molecule;pleiotrophin), which activates the cortactin-src kinase signaling pathway. This leads to rapid neurite extension in neuronal cells, which makes syndecan-3 as an interesting transmembrane receptor in neuronal development and regeneration. However, little is known about the signaling mechanism of syndecan-3. Here we have analyzed formation of ligand-N-syndecan signaling complexes at the cell surface using fluorescence resonance energy transfer (FRET) and bioluminescence resonance energy transfer (BRET). We show that ligand binding leads to dimerization of syndecan-3 at the cell surface. The dimerized syndecan-3 colocalizes with actin in the filopodia of cells. Several amino acid residues (K383, G392 and G396) in the transmembrane domain are shown to be important for the ligand-induced dimerization, whereas the cytosolic domain is not required for the dimerization.展开更多
Constitutively activated G proteins caused by specific mutations mediate the development of multiple malignancies. The mutated Gaq/11 are perceived as oncogenic drivers in the vast majority of uveal melanoma(UM) cases...Constitutively activated G proteins caused by specific mutations mediate the development of multiple malignancies. The mutated Gaq/11 are perceived as oncogenic drivers in the vast majority of uveal melanoma(UM) cases, making directly targeting Gaq/11 to be a promising strategy for combating UM. Herein, we report the optimization of imidazopiperazine derivatives as Gaq/11 inhibitors, and identified GQ262 with improved Gaq/11 inhibitory activity and drug-like properties. GQ262 efficiently blocked UM cell proliferation and migration in vitro. Analysis of the apoptosis-related proteins, extracellular signal-regulated kinase(ERK), and yes-associated protein(YAP) demonstrated that GQ262 distinctly induced UM cells apoptosis and disrupted the downstream effectors by targeting Gaq/11directly. Significantly, GQ262 showed outstanding antitumor efficacy in vivo with good safety at the testing dose. Collectively, our findings along with the favorable pharmacokinetics of GQ262 revealed that directly targeting Gaq/11 may be an efficient strategy against uveal melanoma.展开更多
文摘缓激肽受体是G蛋白偶联受体家族的重要成员之一,它所介导的信号转导对于维持机体内心血管系统动态平衡和炎症方面发挥了重要的作用。近年来,随着荧光共振能量转移(fluorescence resonance energy transfer,FRET)和生物发光共振能量转移(bioluminescence resonance energy trans-fer,BRET)等技术的相继出现,发现缓激肽受体不仅以单体形式存在,还可能以二聚体甚至是高阶寡聚体的形式参与细胞内的病理生理过程。与单体相比,二聚体(或高阶寡聚体)的信号转导和病理功能都产生了相应变化。本文就缓激肽受体及其二聚体所介导的信号途径、生理病理过程及新的研究技术做一简要综述。
文摘Syndecan-3 (N-syndecan) is a transmembrane heparan sulfate proteoglycan abundantly expressed in developing brain. In addition to acting as a coreceptor, syndecan-3 acts as a signaling receptor upon binding of its ligand HB-GAM (heparin-binding growth-associated molecule;pleiotrophin), which activates the cortactin-src kinase signaling pathway. This leads to rapid neurite extension in neuronal cells, which makes syndecan-3 as an interesting transmembrane receptor in neuronal development and regeneration. However, little is known about the signaling mechanism of syndecan-3. Here we have analyzed formation of ligand-N-syndecan signaling complexes at the cell surface using fluorescence resonance energy transfer (FRET) and bioluminescence resonance energy transfer (BRET). We show that ligand binding leads to dimerization of syndecan-3 at the cell surface. The dimerized syndecan-3 colocalizes with actin in the filopodia of cells. Several amino acid residues (K383, G392 and G396) in the transmembrane domain are shown to be important for the ligand-induced dimerization, whereas the cytosolic domain is not required for the dimerization.
基金Supported by National Natural Science Foundation of China(No. 81773618)Shanghai Jiao Tong University Medical-Industrial Crossover Research Program (No. ZH2018QNA13)。
文摘趋化因子及其受体信号通路是肿瘤细胞转移的主要调控因素之一,趋化因子受体CXCR4和XCR1都被证明参与了乳腺癌的进展。本文基于膜蛋白酵母双杂交发现了XCR1-CXCR4这一尚未报道过的相互作用对,进一步通过生物发光共振能量转移技术(bioluminescence resonance energy transfer,BRET)验证并发现XCR1可以竞争性地结合CXCR4受体(P<0.01),形成异源二聚体。在功能方面,首先通过XCR1和CXCR4瞬时转染HEK293细胞进行划痕实验,加入30 nmol/L SDF-1β后,共转组41.55%的伤口愈合率低于单转CXCR4组的58.75%,说明XCR1的共表达抑制了基质细胞衍生因子-1β(SDF-1β)/CXC趋化因子受体4型(CXCR4)信号通路介导的细胞运动性(P<0.05);其次,利用CXCR4-EGFP转基因HEK293细胞系,共表达XCR1后,流式细胞术检测细胞表面CXCR4受体荧光。结果显示,在30 nmol/L SDF-1β的诱导下,XCR1能够加速异源二聚体中CXCR4的内化(P<0.05),使得内化率从14.38%上升到64.10%;最后,分别检测了控制细胞增殖的Akt和控制细胞迁移的ERK信号通路的变化。结果发现,在SDF-1β刺激10 min后,单转CXCR4组的ERK磷酸化为3.59倍,而共转染XCR1/CXCR4组ERK的磷酸化水平仅为2.08倍,二聚化使得ERK磷酸化水平下降,且激活时间缩短;而Akt的磷酸化水平几乎不受影响。本研究揭示了CXCR4和XCR1二聚化现象,以及该二聚体对CXCR4介导的细胞运动性、受体内化和ERK磷酸化的影响。提示靶向XCR1的药物可以成为CXCR4交叉脱敏的候选药物,对于抑制乳腺癌转移提供了一个可供选择的思路。
基金financial support by National Natural Science Foundation of China (No.22077144 and 81973359)Guangdong Natural Science Funds for Distinguished Young Scholar (No.2018B030306017,China)+4 种基金Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery (2019B030301005,China)Key Reasearch and Development Program of Guangdong Province (2020B1111110003,China)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01Y093,China)National Engineering and Technology Research Center for New Drug Druggability Evaluation (Seed Program of Guangdong Province,2017B090903004)Jilin Province Science and Technology Development Project (20200404105YY)。
文摘Constitutively activated G proteins caused by specific mutations mediate the development of multiple malignancies. The mutated Gaq/11 are perceived as oncogenic drivers in the vast majority of uveal melanoma(UM) cases, making directly targeting Gaq/11 to be a promising strategy for combating UM. Herein, we report the optimization of imidazopiperazine derivatives as Gaq/11 inhibitors, and identified GQ262 with improved Gaq/11 inhibitory activity and drug-like properties. GQ262 efficiently blocked UM cell proliferation and migration in vitro. Analysis of the apoptosis-related proteins, extracellular signal-regulated kinase(ERK), and yes-associated protein(YAP) demonstrated that GQ262 distinctly induced UM cells apoptosis and disrupted the downstream effectors by targeting Gaq/11directly. Significantly, GQ262 showed outstanding antitumor efficacy in vivo with good safety at the testing dose. Collectively, our findings along with the favorable pharmacokinetics of GQ262 revealed that directly targeting Gaq/11 may be an efficient strategy against uveal melanoma.
