中缅树鼩UCP2 cDNA核心片段的序列分析

Analysis of the Partial cDNA Sequence of UCP2 Gene in Tupaia belangeri

解偶联蛋白2(UCP2)是近年新发现的一种解偶联蛋白,具有多种生物学活性,相关研究表明,UCP2可以抑制某些细胞(如免疫细胞等)线粒体活性氧的过量生成。本研究通过设计简并引物进行RT-PCR从中缅树鼩(Tupaia belangeri)肝中获得UCP2基因cDNA核心序列。该片段长745 bp,推测氨基酸序列为248个氨基酸。结构功能分析发现,此段氨基酸序列具有2个线粒体内膜载体蛋白特征结构、5个跨膜α-螺旋结构域、1个嘌呤结合区域(PNBD)以及3个解耦联蛋白质的特征序列。中缅树鼩UCP2氨基酸序列与普氏野马(Equus caballus)、小家鼠(Mus musculus)、家犬(Canis lupus familiaris)、人(Homo sapiens)、褐家鼠(Rattus norvegicus)、豚鼠(Cavia porcellus)、苏门达腊猩猩(Pongo abelii)、加卡利安鼠(Phodopus sungorus)和马铁菊头蝠(Rhinolophus ferrumequinum)UCP2进行比较,氨基酸同源性均在90%以上。同时,本研究通过MEGA5构建系统树,对UCP2分子进化特征进行了一定的探讨。

Uncoupling protein 2 （UCP2） is a recently discovered uncoupling protein, which possesses various biological activities. For example, UCP2 has the ability to inhibit the excessive generation of mitochondrial reactive oxygen species in certain cells, such as immune cells. In our research, we designed primers for RT- PCR, and obtained the core sequence in the eDNA of UCP2 from Tupaia belangeri. This core sequence was 750 bp, encoding 248 amino acids. After structure-function analysis, we found that the fragment composed of these amino acids possessed two mitochondrial carrier protein motifs, five potential transmembrane c^-helix domains, one purine-nueleotide binding domain （PNBD） and three UCP-specific sequences. When comparing the amino acid sequence of UCP2 from T. belangeri with that from Equus caballus, Mus musculus, Canis lupus familiaris, Homo sapiens, Rattus norvegicus, Carla porcellus, Pongo abelii, Phodopus sungorus, or Rhinolophus ferrumequinum, we founded that it shared over 90% identity with others. At the same time, we built the phylogenetic tree of UCP2 through MEGA5 to explore its characteristics of molecular evolution.