Chattopadhyay Amitabha, Jafurulla Md, Pucadyil Thomas J
Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad , 500 007, India.
Biosci Rep. 2006 Apr;26(2):79-87. doi: 10.1007/s10540-006-9009-9.
The serotonin1A receptor is the most extensively studied member of the family of seven transmembrane domain G-protein coupled serotonin receptors. Since a large portion of such transmembrane receptors remains in contact with the membrane lipid environment, lipid-protein interactions assume importance in the structure-function analysis of such receptors. We have earlier reported the requirement of cholesterol for serotonin1A receptor function in native hippocampal membranes by specific depletion of cholesterol using methyl- beta-cyclodextrin. In this paper, we monitored the serotonin1A receptor function in membranes that are enriched in cholesterol using a complex prepared from cholesterol and methyl-beta-cyclodextrin. Our results indicate that ligand binding and receptor/G-protein interaction of the serotonin1A receptor do not exhibit significant difference in native and cholesterol-enriched hippocampal membranes indicating that further enrichment of cholesterol has little functional consequence on the serotonin1A receptor function. These results therefore provide new information on the effect of cholesterol enrichment on the hippocampal serotonin1A receptor function.
5-羟色胺1A受体是七个跨膜结构域G蛋白偶联5-羟色胺受体家族中研究最为广泛的成员。由于这类跨膜受体的很大一部分仍与膜脂环境接触，脂-蛋白相互作用在这类受体的结构-功能分析中具有重要意义。我们之前曾报道，通过使用甲基-β-环糊精特异性去除胆固醇，发现天然海马膜中5-羟色胺1A受体功能需要胆固醇。在本文中，我们使用由胆固醇和甲基-β-环糊精制备的复合物，监测了富含胆固醇的膜中5-羟色胺1A受体的功能。我们的结果表明，在天然和富含胆固醇的海马膜中，5-羟色胺1A受体的配体结合和受体/G蛋白相互作用没有显著差异，这表明胆固醇的进一步富集对5-羟色胺1A受体功能几乎没有功能影响。因此，这些结果提供了关于胆固醇富集对海马5-羟色胺1A受体功能影响的新信息。
