Quantification of Gi-Mediated Inhibition of Adenylyl Cyclase Activity Reveals That UDP Is a Potent Agonist of the Human P2Y14 Receptor
Quantification of Gi-Mediated Inhibition of Adenylyl Cyclase Activity Reveals That UDP Is a Potent Agonist of the Human P2Y14 Receptor
复制标题
DOI：
10.1124/mol.109.058578
复制
发表时间：
2009-12-01
影响因子：
3.6
通讯作者：
Harden, T. Kendall
中科院分区：
文献类型：
--
作者：
Carter, Rhonda L.;Fricks, Ingrid P.;Harden, T. Kendall
P2 Y（14）受体最初被鉴定为由UDP-葡萄糖和其他核苷酸糖激活的G蛋白偶联受体。我们已经开发了几种稳定表达人P2 Y（14）受体的细胞系，允许容易地检查其与天然G（i）家族G蛋白的偶联及其相关的下游信号传导途径（J Pharmacol Exp Ther 330：162-168，2009）。在目前的研究中，我们研究了P2 Y（14）受体依赖性抑制环AMP积累的人胚肾（HEK）293，C6胶质瘤，和中国仓鼠卵巢（CHO）细胞稳定表达这种受体。人P2 Y（14）受体不仅被UDP-葡萄糖激活，而且也被UDP激活。UDP和UDP-葡萄糖的表观功效相似，在HEK 293、CHO和C6胶质瘤细胞中UDP依赖性激活P2 Y（14）受体的EC 50值（74、33和29 nM）分别与UDP-葡萄糖的EC 50值（323、132和72 nM）相似。UDP和UDP-葡萄糖也刺激表达P2 Y（14）受体的HEK 293细胞中的细胞外信号调节激酶（ERK）1/2磷酸化，但在野生型HEK 293细胞中不刺激。UDP的一系列类似物是有效的P2 Y（14）受体激动剂，但天然存在的核苷二磷酸、CDP、GDP和ADP表现出的激动剂效力比用UDP观察到的效力低100倍以上。鉴定出两种UDP类似物，其选择性激活P2 Y（14）受体而不是UDP激活的P2 Y（6）受体，并且这些分子刺激分化的人早幼粒白血病细胞中ERK 1/2的磷酸化，所述细胞天然表达P2 Y（14）受体，但对野生型HL-60细胞没有影响，所述细胞不表达所述受体。我们的结论是UDP是一个重要的同源激动剂的人P2 Y（14）受体。
The P2Y(14) receptor was initially identified as a G protein-coupled receptor activated by UDP-glucose and other nucleotide sugars. We have developed several cell lines that stably express the human P2Y(14) receptor, allowing facile examination of its coupling to native G(i) family G proteins and their associated downstream signaling pathways (J Pharmacol Exp Ther 330: 162-168, 2009). In the current study, we examined P2Y(14) receptor-dependent inhibition of cyclic AMP accumulation in human embryonic kidney (HEK) 293, C6 glioma, and Chinese hamster ovary (CHO) cells stably expressing this receptor. Not only was the human P2Y(14) receptor activated by UDP-glucose, but it also was activated by UDP. The apparent efficacies of UDP and UDP-glucose were similar, and the EC50 values (74, 33, and 29 nM) for UDP-dependent activation of the P2Y(14) receptor in HEK293, CHO, and C6 glioma cells, respectively, were similar to the EC50 values (323, 132, and 72 nM) observed for UDP-glucose. UDP and UDP-glucose also stimulated extracellular signal-regulated kinase (ERK) 1/2 phosphorylation in P2Y(14) receptor-expressing HEK293 cells but not in wild-type HEK293 cells. A series of analogs of UDP were potent P2Y(14) receptor agonists, but the naturally occurring nucleoside diphosphates, CDP, GDP, and ADP exhibited agonist potencies over 100-fold less than that observed with UDP. Two UDP analogs were identified that selectively activate the P2Y(14) receptor over the UDP-activated P2Y(6) receptor, and these molecules stimulated phosphorylation of ERK1/2 in differentiated human HL-60 promyeloleukemia cells, which natively express the P2Y(14) receptor but had no effect in wild-type HL-60 cells, which do not express the receptor. We conclude that UDP is an important cognate agonist of the human P2Y(14) receptor.