摘 要:目的 分离、克隆镰形扇头蜱一新基因。 方法 本实验从镰形扇头蜱半饱血雌蜱唾液腺cDNA文库的100个EST(Expressed Sequence Tag)序列中选取一个带有polyA尾的序列，经5'RACE(Rapid Amplification of cDNA Ends)得到此序列的全长基因，命名为 RhHp2 ，基因全长 1 002bp ，开放阅读框(ORF)从31bp至879bp，共848bp，编码282个氨基酸。经序列比较，RhHp2 基因与其它序列在核苷酸水平上基本无同源性，但在氨基酸水平上与其它物种同源性最高可达50.81% 。 RhHp2 基因连接于PET32a(+)载体后克隆于表达菌BL21，1mM IPTG诱导表达，产生分子量约为55kD的融合重组蛋白，并以不溶性包涵体形式存在。经纯化和体外复性的重组蛋白三次免疫新西兰 兔后，将镰形扇头蜱未吸血成蜱和若蜱接种于此免疫兔耳，并对接种48h 后的蜱上体数、蜱的饱血数量、饱血时间、饱血重量等进行记录。 结果 发现蜱的吸血行为受到一定影响，若蜱在48h的减虫率(上体数减少)为58%，在整个吸血过程中的死亡数增加，成蜱的饱血体重显著降低。结论 此结果表明 RhHp2 基因的重组表达产物具有一定的免疫保护作用。

    关键词: 镰形扇头蜱; RhHp2 基因;表达

    ISOLATION， CLONING， EXPRESSION AND ANTI-TICK EFFECT ANALYSIS OF A NOVEL GENE FROM Rhipicephalus haemaphysaloides haemaphysaloides

    GONG Hai-yan， ZHOU Jin-lin， ZHOU Yong-zhi， XIANG Fei-yu， QIN Yu-tao

    (Shanghai Institute of Domestic Animal Parasitology， Chinese Academy of Agricultural Sciences; Key Library of Animal Parasitology， Ministry of Agriculture， Shanghai 200232， China)

    Abstract: A sequence with poly A was selected from the 100 expressed sequence tags obtained from the cD- NA library of salivary gland of feeding female Rhipicephalus haemaphysaloides haemaphysaloides for the present study. 5' rapid amplification of cDNA ends (RACE) was performed with primers based on the related sequence and the full length of the gene named as RhHp2 was obtained. The gene contains 1002 bp and its coding region is from 31bp to 879bp (total 848bp) ......