吸血诱导的埃及伊蚊海口株后期胰蛋白酶基因测序及与美国株同源性比较

应用逆转录-聚合酶链式反应（RT-PCR）技术从吸血后24 h埃及伊蚊海口株总RNA中扩增出了后期胰蛋白酶编码区cDNA序列。采用自动DNA分析仪进行序列分析，并与已知埃及伊蚊美国株后期胰蛋白酶基因及推导的氨基酸序列进行了同源性比较。结果表明：埃及伊蚊海口株后期胰蛋白酶基因序列与美国株同源性达98%，有11个碱基发生变异；氨基酸同源性达99%，仅有3个氨基酸发生变异，但与催化位点密切相关的氨基酸及N末端氨基酸序列完全一致。以上结果显示，埃及伊蚊胰蛋白酶不同地理株间存在微小的差异。

Cloning and sequencing of the blood meal-induced late trypsin gene from Aedes ae-gypti Haikou strain

This paper reports a cDNA sequence and its deduced amino acid sequence in the late trypsin of Aedes aegypti Haikou strain. The cDNA fragment from the whole body of adult Aedes aegypti in 24 h after blood ingesting was amplified by RT-PCR and its specificity was confirmed by electrophoresis. The cDNA was inserted into pGEM T easy vector and transformed into E.coli JM109. The positive clone was sequenced by an automatic DNA sequencer. The cDNA and the deduced amino acid sequence were highly homologous with the late trypsin from the Aedes aegypti American strain, showing 98% and 99% similarity, respectively. The deduced amino acid sequence is highly homologous with those of other mosquitos' trypsins in both residues around the catalytic pocket and N-terminal sequences.