中文摘要：

以桔全爪螨Panonychuscitri（MeGregor）为研究对象，利用RT-PCR和SMART RACE技术克隆获得其几丁质合成酶基因的全长 cDNA序列（命名为PcCHS，GenBank登录号为 KM242063），并利用生物信息学方法对序列进行分析。结果表明：桔全爪螨几丁质合成酶 PcCHS基因的 cDNA全长为4925 bp，其中5’非翻译区（5’-UTR）为155 bp，3’非翻译区（3’-UTR）为345 bp，开放阅读框（ORF）包含4425 bp，编码1474个氨基酸，预测其蛋白质分子质量约为168．43kD，理论等电点为6．83。其包含EDR和 QRRRW这2个几丁质合成酶基因的标签序列。ExPASy在线分析表明，PcCHS具有15个跨膜螺旋、4个糖基化位点。推导的氨基酸序列同源性分析结果表明：桔全爪螨与二斑叶螨相似度为89％，其次为西方盲走螨，相似度为55％。分子系统进化的结果也表明桔全爪螨与二斑叶螨和西方盲走螨的进化关系最近。

英文摘要：

In this paper,the complementary DNA （cDNA）of the chitin synthase from Panonychus citri （MeGregor）was cloned.The P.citri CHS cDNA （AC：KM242063 ）was 4925bp long and consisted of a 155bp 5＆#39;-untranslated region （UTR）,a 345bp 3＆#39;-UTR,and a 4425bp open reading frame （ORF）encoding a 1474-amino-acid protein.The predicted molecular mass was 168.43 kD and theoretical isoelectric point （pI） was 6.83.The protein contained the signature sequences of chitin synthase gene,which were EDR and QR-RRW.Using ExPASy software online,it was found that the amino acid sequence for P.citri CHS contained fifteen putative transmembrane regions and four potential N-glycosylation sites.Comparing the amino acid sequence of P.citri CHS with other known CHS gene sequences,we found that it shared the highest simi-larity （89%）with Tetranychusurticae and 55% with Metaseiulus occidentalis.Phylogenetic analysis also suggested that the P.citri CHS amino acid sequence clustered together with Tetranychus urticae and Metaseiulus occidentalis.