鲤胸腺素Tβ全长cDNA的克隆与序列分析

Cloning and sequence analysis of common carp (Cyprinus carpio L. ) beta-thymosin

应用荧光DDRT-PCR从鲤外周血白细胞克隆了鲤胸腺素β(thymosinβ,Tβ)基因cDNA全序列。序列分析表明,TβcDNA全长528bp,其完整的读码框架位于40～178bp,编码46个氨基酸,5'非编码区长39bp,3'非编码区长为348bp,且具有Poly(A)加尾信号(AATAAA),将该基因序列递呈GenBank,注册序列号为AY457946。氨基酸序列同源性分析显示,鲤Tβ氨基酸序列与鲤Tβa、斑马鱼Tβa及斑马鱼Tβ-2同源性均为84%。在系统发生树上,鲤Tβ与鲤、斑马鱼、白斑狗鱼和鲑Tβa及斑马鱼Tβ2聚类。

The thymosinβ（Tβ） gene was cloned from the carp peripheral blood leucocytes by fluorescence differential display reverse transcriptase chain reaction（fluoroDDRT-PCR） .The full-length thymosinβ cDNA was 528 bp with the open reading frame located from 40 bp to 178 bp,encoding 46 amino acid residues.Its 5＇ untranslated region（UTR） is 39 bp and 3＇ UTR is 348 bp which contains poly（A） signal（AATAAA） and poly （A） tail.Its GenBank Accession Number is AY457946.The deduced amino acid sequences of the carp Tβ possessed 84% ,84% ,and 84% similarity with the Tβ a of Cyprinus carpio,Tβ a of Danio rerio and beta thymosin-like protein 2 of Danio rerio.The carp Tβ were clustered with Tβ a of Cyprinus carpio,Tβ a of Danio rerio,Tβ a of Esox lucius,Tβ a of Salmo salar and beta thymosin-like protein 2 of Danio rerio.It is essential for a complete understanding of the mechanisms of thymosinβ in immune response of fish.