微小牛蜱铁蛋白编码基因的克隆和分析

从微小牛蜱克隆到1个新的铁蛋白编码基因，cDNA全长642bp，编码区为123-639bp，编码172个氨基酸残基，该蛋白预测的分子量为19．9ku，等电点为4．24。经过分析，其预测氨基酸序列与已报道的变异革蜱、非洲钝缘蜱和蓖子硬蜱铁蛋白同源性分别为93．60％、88．37％和83．72％。且核苷酸序列在mRNA 5’未翻译区(5’UTR)的茎环结构存在铁应答元件(IRE)，其氨基酸序列上带有典型的亚铁氧化酶中心结构的保守序列。RT-PCR分析表明，该基因在微小牛蜱卵、幼蜱、半饱血雌蜱、饱血雌蜱和雄蜱这几个阶段均有表达。

Molecular Cloning and Analysis of Ferritin of Boophilus Microplus

A gene encoding ferritin was isolated and cloned from B. microplus. The cDNA is composed of 642 nucleotides and encoding 172 amino-acid residues, the encoding region is between 123bp to 639bp, the deduced mass is 19.9ku and isoelectric point is 4.24.The deduced amino-acid sequence shows 93.60%, 88.37% and 83.72% similarities with the ferritin from tick Dermacentor variabilis, Ixoded ricinus, and Ornithodoros moubata respectively. The stem-loop structure of a putative iron responsive element is found in the 5-untranslated region of ferritin mRNA. The protein contains the conserved motifs for ferroxidase center. RT-PCR analysis suggests the ferritins are expressed in the eggs,larvas,fed female adult,engorgement female adult and male adult ticks of B. microplus.