The origin and diversification of human temperature sensory receptors.

人类温度感觉受体的起源和多样化。

基本信息

批准号：
17570004
负责人：
SATTA Yoko
金额：
$ 2.24万
依托单位：
The Graduate University for Advanced Studies
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

Animals sense ambient physico-chemical fluctuations through receptors in their sensory systems. The temperature sensors are capable of detecting and discriminating stimuli over a broad spectrum of temperatures. These sensors are members of three subfamilies (TRP V, TRPM and TRPA) of the transient receptor potential (TRP) family. In this project, there are two aims : 1) To infer the molecular evolution of these temperature receptors and 2) to clarify the origin of the diversity among human thermo-sensory receptors.1)Molecular evolution of temperature receptors in vertebrates : A larger number of TRP paralogs have been found in terrestrial animal genomes than in the fish genome, reflecting different extent of temperature fluctuations in environments. In mammals, there are nine thermo-sensory receptor genes, of which four (TRPV1'4) are responsible for sensing either warm or hot. Phylogenetic studies of TRPV1-.4 genes in vertebrates have revealed excessive amino acid substitutions in the stem lineage of birds and mammals for each TRPV, suggesting either accelerated substitution rates or frequent occurrences of convergent evolution. These substitutions may be related to the development of body temperature controlling system in warm-blooded animals.2)The origin of the diversity among human thermo-sensory receptors : In NCBI record, there is a record of TRPV1 pseudogene. To examine the distribution of this pseudogene over the world, I sequenced approximately 5kb region encompassing exon9 to 11 encoding the 6 trans-membrane region of TRPV1 from 68 individuals from 18 different ethnic groups. However, there is no example o pseudogene in our sample. Other population genetics analyses are progressing and the result will be submitted to an international journal within 2007.3)In addition to the above results, a review (in Japanese) about a role of sensory receptors in the human evolution has been published.

动物通过感觉系统中的受体感知周围的物理化学波动。温度传感器能够检测和区分各种温度范围内的刺激。这些传感器属于瞬时受体电位 (TRP) 家族的三个亚家族（TRP V、TRPM 和 TRPA）的成员。在这个项目中，有两个目标：1）推断这些温度受体的分子进化，2）阐明人类热感觉受体多样性的起源。1）脊椎动物温度受体的分子进化：数量更多在陆地动物基因组中发现的 TRP 旁系同源物比在鱼类基因组中发现的 TRP 旁系同源物多，反映了环境中不同程度的温度波动。在哺乳动物中，有九个热感觉受体基因，其中四个 (TRPV1'4) 负责感知温暖或炎热。对脊椎动物 TRPV1-.4 基因的系统发育研究表明，鸟类和哺乳动物的茎谱系中每个 TRPV 存在过多的氨基酸替换，表明替换率加快或趋同进化频繁发生。这些取代可能与温血动物体温控制系统的发育有关。2)人类热感觉受体多样性的起源：在NCBI记录中，有TRPV1假基因的记录。为了检查该假基因在世界各地的分布，我对来自 18 个不同种族的 68 个人的大约 5kb 区域进行了测序，该区域包含外显子 9 至 11，编码 TRPV1 的 6 个跨膜区域。然而，我们的样本中没有假基因的例子。其他群体遗传学分析正在进行中，结果将在2007年内提交给国际期刊。3）除了上述结果之外，还发表了一篇关于感觉受体在人类进化中的作用的综述（日文）。