Cloning and sequence analysis of chitin synthase gene fragments of Demodex mites  

作　　者：Ya-e ZHAO Zheng-hang WANG Yang XU Ji-ru XU Wen-yan LIU Meng WEI Chu-ying WANG 

机构地区：[1]Department of Immunology and Pathogen Biology,Xi'an Jiaotong University College of Medicine,Xi'an 710061,China

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2012年第10期763-768,共6页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project supported by the National Natural Science Foundation of China (No. 81271856);the National College of Innovative Experimental Projects of China (No. 101069819)

摘　　要：To our knowledge,few reports on Demodex studied at the molecular level are available at present.In this study our group,for the first time,cloned,sequenced and analyzed the chitin synthase(CHS) gene fragments of Demodex folliculorum,Demodex brevis,and Demodex canis(three isolates from each species) from Xi'an China,by designing specific primers based on the only partial sequence of the CHS gene of D.canis from Japan,retrieved from GenBank.Results show that amplification was successful only in three D.canis isolates and one D.brevis isolate out of the nine Demodex isolates.The obtained fragments were sequenced to be 339 bp for D.canis and 338 bp for D.brevis.The CHS gene sequence similarities between the three Xi'an D.canis isolates and one Japanese D.canis isolate ranged from 99.7% to 100.0%,and those between four D.canis isolates and one D.brevis isolate were 99.1%-99.4%.Phylogenetic trees based on maximum parsimony(MP) and maximum likelihood(ML) methods shared the same clusters,according with the traditional classification.Two open reading frames(ORFs) were identified in each CHS gene sequenced,and their corresponding amino acid sequences were located at the catalytic domain.The relatively conserved sequences could be deduced to be a CHS class A gene,which is associated with chitin synthesis in the integument of Demodex mites.To our knowledge,few reports on Demodex studied at the molecular level are available at present.In this study our group,for the first time,cloned,sequenced and analyzed the chitin synthase（CHS） gene fragments of Demodex folliculorum,Demodex brevis,and Demodex canis（three isolates from each species） from Xi＇an China,by designing specific primers based on the only partial sequence of the CHS gene of D.canis from Japan,retrieved from GenBank.Results show that amplification was successful only in three D.canis isolates and one D.brevis isolate out of the nine Demodex isolates.The obtained fragments were sequenced to be 339 bp for D.canis and 338 bp for D.brevis.The CHS gene sequence similarities between the three Xi＇an D.canis isolates and one Japanese D.canis isolate ranged from 99.7% to 100.0%,and those between four D.canis isolates and one D.brevis isolate were 99.1%-99.4%.Phylogenetic trees based on maximum parsimony（MP） and maximum likelihood（ML） methods shared the same clusters,according with the traditional classification.Two open reading frames（ORFs） were identified in each CHS gene sequenced,and their corresponding amino acid sequences were located at the catalytic domain.The relatively conserved sequences could be deduced to be a CHS class A gene,which is associated with chitin synthesis in the integument of Demodex mites.

关 键 词：DEMODEX Chitin synthase genes Cloning and sequencing Phylogenetic study Function analysis 

分 类 号：R384.4[医药卫生—医学寄生虫学] R757.3[医药卫生—基础医学]