目的 克隆表达埃及伊蚊黄蛋白c（Aael-yellow-c）基因,并探讨rAael-yellow-c蛋白体外抗凝血作用。 方法 RT-PCR扩增Aael-yellow-c成熟肽基因,纯化后的片段与pEASY-E1载体连接,转化至大肠埃希菌DH5α感受态细胞,取菌液进行PCR、双酶切和测序鉴定。0.1 mol/L异丙基-β-D-硫代半乳糖苷诱导蛋白表达后,镍柱亲和层析纯化重组蛋白,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和蛋白质免疫印迹（Western blotting）分析重组蛋白表达情况。比浊法观察不同浓度rAael-yellow-c蛋白对二磷酸腺苷诱导的血小板聚集活性影响。手工法检测不同浓度rAael-yellow-c蛋白对人血浆凝血酶原时间（PT）、部分凝血活酶时间（APTT）及凝血酶时间（TT）的影响。采用SPSS 18.0统计软件进行统计学分析,组间差异比较采用t检验。 结果 Aael-yellow-c基因CDS区为1 287 bp,含27个氨基酸组成的信号肽,成熟肽序列长1 200 bp,编码399个氨基酸。RT-PCR扩增获得Aael-yellow-c基因片段,大小约为1 200 bp。菌液PCR、双酶切和测序鉴定显示,pEASY-E1-Aael-yellow-c质粒构建成功。SDS-PAGE结果显示,重组蛋白以包涵体形式表达;镍柱亲和层析纯化重组蛋白后获得单一条带。Western blotting结果显示,该蛋白可被His-tag抗体和抗rAael-yellow-c蛋白的兔血清多克隆抗体识别。血小板聚集抑制实验结果显示,2 083.30、416.66、83.33、16.67和3.33 nmol/L rAael-yellow-c蛋白可抑制由ADP诱导的血小板聚集,差异具有统计学意义（t = 7.09、10.39、5.39、10.54和8.93,P < 0.01）,其中3.33 nmol/L的重组蛋白对ADP诱导的血小板聚集抑制作用最强,抑制率为（59.27 ± 11.90）%;0.67、0.13和0.02 nmol/L的重组蛋白对ADP诱导的血小板聚集作用无影响（t = 2.10、1.33和0.00,P > 0.05）。内外源凝血实验结果显示,与阴性对照组相比,0.12、1.20 和12.00 μmol/L rAael-yellow-c分别作用于人血浆时,PT分别为13.63~14.10、13.32~14.38和13.55~16.01 s,差异无统计学意义（t = 1.33、0.63和1.00,P > 0.05）;APTT分别为32.76~38.46、31.94~41.78和33.34~39.29 s,差异无统计学意义（t = 0.47、0.06和0.24,P > 0.05）;TT分别为19.12~21.20、19.7~23.12和21.85~25.30 s,差异无统计学意义（t = 0.47、0.24和1.60,P > 0.05）。 结论 获得的rAael-yellow-c蛋白主要通过抑制ADP诱导的血小板聚集作用帮助蚊虫吸血。

Objective To clone and express the Aedes aegypti yellow-c(Aael-yellow-c) gene and investigate the in vitro anticoagulation activity of recombinant Aael-yellow-c protein. Methods The Aael-yellow-c mature peptide gene was amplified by RT-PCR, and the purified target gene segment obtained was connected to the plasmid pEASY-E1, which was transformed into Escherichia coli DH5α competent cell. The clones were verified with PCR, double restriction enzymes and sequencing. After induction with 0.1 mol/L IPTG, the recombinant protein was purified by Ni-affinity chromatography and identified by SDS-PAGE and Western blotting. The effect of rAael-yellow-c protein on human platelet aggregation induced by adenosine diphosphate (ADP) was observed by turbidimetry. The affect of rAael-yellow-c at different concentrations on prothrombin time (PT), activated thromboplastin time (APTT) and thrombin time (TT) of human blood plasma was detected manually. Results A 1 200 bp fragment of Aael-yellow-c gene was obtained by RT-PCR, and an pEASY-E1-Aael-yellow-c plasmid was successfully constructed by PCR, double restriction enzymes and sequencing. The recombinant protein was expressed in the form of inclusion body confirmed by SDS-PAGE and Western blotting, the purified recombinant protein was obtained by Ni-NTA. The results of the platelet aggregation inhibition experiment showed that 2083.30, 416.66, 83.33, 16.67 and 3.33 nmol/L rAael-yellow-c protein could inhibit platelet aggregation induced by ADP, and the difference was statistically significant(t = 7.09, 10.39, 5.39, 10.54 and 8.93, P < 0.01). The strongest inhibition effect was at 3.33 nmol/L, and the inhibitory rate was (59.27 ± 11.90)%; The recombinant proteins of 0.67, 0.13 and 0.02 nmol/L had no effect on ADP induced platelet aggregation, and the results were not statistically different (t = 2.10, 1.33 and 0.00, P > 0.05); The results the of internal and external source coagulation test showed that compared with the negative control group, rAael-yellow-c (0.12, 1.20 and 12.00 μmol/L) treated human plasma had PT of 13.63-14.10 s, 13.32-14.38 s and 13.55-16.01 s. The difference was not statistically significant (t = 1.33, 0.63 and 1.00, P > 0.05). APTT was 32.76-38.46 s, 31.94-41.78 s and 33.34-39.29 s, the difference was not statistically significant (t = 0.47, 0.06 and 0.24, P > 0.05). TT was 19.12-21.20 s, 19.7-23.12 s, 21.85-25.3 s, the difference was not statistically significant (t = 0.47, 0.24 and 1.60, P > 0.05). Conclusion The recombinant Aael-yellow-c protein obtained may be aidful for mosquito in blood sucking through suppressing platelet aggregation induced by ADP.