Development of swich on-off type probes for detection of GPCR dimers

G蛋白偶联受体在细胞表面的组装状态引起了人们的极大兴趣，因为G蛋白偶联受体的多聚体在细胞功能中起着关键作用。CXCR4的二价配体与多聚脯氨酸连接，由于多聚脯氨酸螺旋的刚性结构，已被证明是分子标尺。为了扩大刚性连接配体的应用范围，探索GPCR的可能多聚体形式，利用我们的二价型CXCR4型配体，研究了近红外染料标记多-L-脯氨酸连接体的效果。制备了在连接体的中间或末端含有近红外染料的聚L-脯氨酸连接体，并对其荧光性能和结合性能进行了分析，以产生新的开关类型的检测方法。

Assembly status of G protein-coupled receptors (GPCR) on the cellular surface is of great interest because the multimerization of GPCR could play pivotal roles in cellular functions. The bivalent ligands with polyproline linkers for CXCR4 have been shown to work as molecular ruler because of the rigid structure of polyproline helices. To expand the utility of the ligands with rigid linkers and explore the possible multimeric form of GPCR, the effect of near infrared dye labeling for the poly-L-proline linkers were addressed utilizing our bivalent-type CXCR4 ligand. The poly-L-proline linkers containing the NIR-dye at the middle or end of the linkers were prepared and their fluorescent and binding properties were analyzed to produce novel detection methods with a switch-on-off type .