Structural insight into the role of the human melanocortin 3 receptor cysteine residues on receptor function.
Structural insight into the role of the human melanocortin 3 receptor cysteine residues on receptor function.
复制标题
DOI：
10.1016/j.peptides.2011.09.024
复制
发表时间：
2011-12
期刊：
影响因子：
3
通讯作者：
Harmon CM
中科院分区：
文献类型：
--
作者：
Yang Y;Chen M;McPherson D;Mishra V;Harmon CM
Melanocortin-3 受体 (MC3R) 在下丘脑和大脑边缘系统以及外周部位表达，在能量稳态和其他生理功能的调节中发挥着重要作用。过去的研究表明，MC3R 缺陷会导致小鼠和人类的脂肪量增加、喂养效率增加、高瘦素血症和轻度高胰岛素血症。 MC3R属于G蛋白偶联受体(GPCR)家族，许多研究表明GPCR中的一些半胱氨酸残基在维持受体三级结构和功能中发挥着关键作用。在这项研究中，我们研究了 MC3R 中半胱氨酸残基对受体功能的作用。人类 MC3R (hMC3R) 有 18 个半胱氨酸残基，它们位于细胞外环 (EL)、跨膜结构域 (TM) 和细胞内环 (IL)。我们用丝氨酸取代这些半胱氨酸，并在缺乏内源性 MC3R 的 HEK-293 细胞中表达这些受体。我们的结果表明，十八个 hMC3R 中的五个半胱氨酸对于 hMC3R 功能很重要。 EL3 中的突变 C305S、C311S 和 C313S 导致受体表达和受体功能显着降低，而 TM3 中的另外两个突变 C115S 和 C162S 显着降低 NDP-MSH 结合亲和力和效力。这些结果表明，细胞外半胱氨酸残基 305、311 和 313 对于受体表达至关重要，而跨膜半胱氨酸残基 C115 和 162 对于配体结合和信号转导也很重要。这些发现为 hMC3R 的半胱氨酸残基对受体三级结构和功能的重要性提供了重要的见解。
Melanocortin-3 receptor (MC3R), expressed in the hypothalamus and limbic systems of the brain, as well as by peripheral sites, plays an important role in the regulation of energy homeostasis and other physiological functions. Past work shows that MC3R-deficiency resulted in fat mass increase, feeding efficiency increase, hyperleptinemia and mild hyperinsulinemia in mice and human. MC3R belongs to G-protein coupled receptor (GPCR) family and many studies indicate that some cysteine residues in GPCR play key roles in maintaining receptor tertiary structure and function. In this study, we examined the role of cysteine residues in MC3R on receptor function. Human MC3R (hMC3R) has eighteen cysteine residues where they are located in the extracellular loops (ELs), the transmembrane domains (TMs) and the intracellular loops (ILs). We replaced these cysteines with serine and expressed these receptors in HEK-293 cells which lack endogenous MC3R. Our results indicate that five cysteines in eighteen of the hMC3R are important for hMC3R function. Mutations, C305S, C311S, and C313S in EL3, resulted in significant decrease in receptor expression and receptor function while two other mutations C115S and C162S in TM3 significantly decreased NDP-MSH binding affinity and potency. These results suggest that extracellular cysteine residue 305, 311 and 313 are crucial for receptor expression and the transmembrane cysteine residue, C115 and 162 are important for ligand binding and signaling. These findings provide important insights into the importance of cysteine residues of hMC3R on receptor tertiary structure and function.
登录
查看更多内容
影响因子：
120.7
作者：
Flegal, KM;Carroll, MD;Johnson, CL
通讯作者：
Johnson, CL
影响因子：
4.8
作者：
Cook, JVF;Eidne, KA
通讯作者：
Eidne, KA
影响因子：
56.9
作者：
KOBILKA, BK;KOBILKA, TS;LEFKOWITZ, RJ
通讯作者：
LEFKOWITZ, RJ
DOI：
10.1006/bbrc.2001.4429
发表时间：
2001-03-09
影响因子：
3.1
作者：
Frändberg, PA;Doufexis, M;Chhajlani, V
通讯作者：
Chhajlani, V
影响因子：
4.8
作者：
Chen, Min;Cai, Minying;Yang, Yingkui
通讯作者：
Yang, Yingkui