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从缢蛏(Sinonovacula constricta)cDNA文库中筛选出一条铁蛋白同源序列,直接扩增质粒获得全长cDNA序列,共1 106 bp,包括128 bp的5’非翻译区和309 bp的3’非翻译区,以及669 bp的开放阅读框。阅读框共编码222个氨基酸,N端含有17个氨基酸的信号肽序列,推算的分子量约为25.47 ku,理论等电点为5.48。氨基酸序列分析结果表明,该基因含有保守的铁氧化酶活性中心的7个氨基酸残基,但是不具有糖基化位点(NQS)和5’非编码区铁蛋白的铁反应元件(iron response element,IRE),属于H型铁蛋白基因,该基因被命名为ScFERs。系统进化显示,基本上同一个物种的不同亚型铁蛋白首先聚在一起,然后和其他物种的铁蛋白聚在一起。缢蛏ScFERs首先与日本花棘石鳖(Liolophura japonica)LjFERs聚在一起,然后与缢蛏另一种ScFER以及文蛤(Meretrix meretrix)MmFERs聚在一起。荧光定量PCR检测结果显示ScFERs基因在肝胰腺中高度表达,肝胰腺与其它组织间的表达量存在着极显著差异。经鳗弧菌(Vibrioanguillarum)和副溶血弧菌(Vibrio parahaemolyticus)诱导后,ScFERs基因表达水平呈显著上调。为进一步研究缢蛏铁蛋白基因的结构和功能奠定了基础。
A ferritin homology sequence was screened from the cDNA library of Sinonovacula constricta. The full-length cDNA sequence was amplified by direct amplification of 1 106 bp, including 128 bp of 5 ’untranslated region and 309 bp of 3’ untranslated region Region, and a 669 bp open reading frame. The reading frame encodes a peptide sequence of 222 amino acids and a 17 amino acid signal peptide at the N-terminus. The estimated molecular weight is about 25.47 ku and the theoretical isoelectric point is 5.48. Amino acid sequence analysis showed that the gene contains seven amino acid residues of the conserved iron oxidase activity center, but does not have the glycosylation site (NQS) and the iron response element of the 5 ’non-coding region ferritin , IRE) belongs to the H-type ferritin gene, which is named ScFERs. Phylogenetic analyzes show that different subtypes of ferritin, which are essentially from the same species, first come together and then come together with ferritin from other species. ScFERs first got together with the LjFERs of Liolophura japonica, then clustered together with another ScFER and the Meretrix meretrix MmFERs. Fluorescent quantitative PCR results showed that ScFERs gene was highly expressed in hepatopancreas, and there was a significant difference in the expression of ScFERs between hepatopancreas and other tissues. After induced by Vibrioanguillarum and Vibrio parahaemolyticus, the expression of ScFERs gene was significantly up-regulated. Which laid the foundation for further study on the structure and function of the ferritin gene.