Niesler Beate, Frank Bernd, Kapeller Johannes, Rappold Gudrun A
Institute of Human Genetics, University of Heidelberg, Im Neuenheimer Feld 328, 69120, Heidelberg, Germany.
Gene. 2003 May 22;310:101-11. doi: 10.1016/s0378-1119(03)00503-1.
For more than 50 years the serotonin system has been the subject of intense research. This has provided an exciting insight and led to the discovery of multiple drugs targeting serotonin receptors, metabolising enzymes and re-uptake sites. During the past few years researchers focussed especially on elucidating the complexity of different physiological actions in the serotonergic network. We have identified two novel human serotonin 5-hydroxytryptamine type 3 receptor-like genes, HTR3D and HTR3E, by performing homology searches using the public human sequence databases and subsequently cloned the full length cDNAs by 5' and 3' rapid amplification of complementary DNA ends. Mapping of HTR3D and HTR3E by hybridisation, polymerase chain reaction and fluorescence in situ hybridisation revealed that both genes together with HTR3C are clustered in a subinterval of less than 100 kb on chromosome 3q27. Comparative expression analysis of all HTR3 genes, namely HTR3A, B, C, D and E showed HTR3D expression to be restricted to kidney, colon and liver and HTR3E expression to colon and intestine, whereas all other genes are widely expressed in many tissues including brain.
五十多年来，5-羟色胺系统一直是深入研究的对象。这为我们提供了令人兴奋的见解，并促使人们发现了多种针对5-羟色胺受体、代谢酶和再摄取位点的药物。在过去几年中，研究人员特别致力于阐明5-羟色胺能网络中不同生理作用的复杂性。我们通过使用公共人类序列数据库进行同源性搜索，鉴定出了两个新的人类5-羟色胺3型受体样基因，即HTR3D和HTR3E，随后通过5'和3'互补DNA末端快速扩增克隆了全长cDNA。通过杂交、聚合酶链反应和荧光原位杂交对HTR3D和HTR3E进行定位分析，结果显示这两个基因与HTR3C一起聚集在3号染色体q27区域小于100 kb的一个亚区间内。对所有HTR3基因，即HTR3A、B、C、D和E进行的比较表达分析表明，HTR3D的表达仅限于肾脏、结肠和肝脏，HTR3E的表达仅限于结肠和小肠，而所有其他基因在包括大脑在内的许多组织中广泛表达。
