title: A novel Schistosoma japonicum endonuclease homologous to DNase II.
abstract: BACKGROUND
  Recent advances in studies of the Schistosoma japonicum genome have opened new avenues for the elucidation of parasite biology and the identification of novel targets for vaccines, drug development and early diagnostic tools.
  
  
  RESULTS
  In this study, we surveyed the S. japonicum genome database for genes encoding nucleases. A total of 130 nucleases of 3 classes were found. Transcriptional analysis of these genes using a genomic DNA microarray revealed that the majority of the nucleases were differentially expressed in parasites of different developmental stages or different genders, whereas no obvious transcriptional variation was detected in parasites from different hosts. Further analysis of the putative DNases of S. japonicum revealed a novel DNase II homologue (Sjda) that contained a highly conserved catalytic domain. A recombinant Sjda-GST protein efficiently hydrolysed genomic DNA in the absence of divalent iron. Western-blot and immunofluorescence assays showed that Sjda was mainly expressed on the teguments of female adult parasites and induced early humoral immune responses in infected mice.
  
  
  CONCLUSIONS
  A novel DNase II homologue, Sjda, was identified in S. japonicum. Sjda was mainly distributed on the teguments of adult female parasites and possessed a typical divalent iron-independent DNA catalytic activity. This protein may play an important role in the host-parasite interaction.
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. hounan@ipbcams.ac.cn.
authors.forename: Nan
authors.initials: N
authors.lastname: Hou
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. piaoxianyu@ipbcams.ac.cn.
authors.forename: Xianyu
authors.initials: X
authors.lastname: Piao
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. puffy_cai@163.com.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Cai
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. wuchuang@ipbcams.ac.cn.
authors.forename: Chuang
authors.initials: C
authors.lastname: Wu
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. liushuai@ipbcams.ac.cn.
authors.forename: Shuai
authors.initials: S
authors.lastname: Liu
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. xiaoyan@ipbcams.ac.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Dong Dan San Tiao 9, Beijing, People's Republic of China. qijun.chen@ipbcams.ac.cn.|Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, Jilin University, Xi An Da Lu 5333, Changchun, People's Republic of China. qijun.chen@ipbcams.ac.cn.
authors.forename: Qijun
authors.initials: Q
authors.lastname: Chen
mesh_terms: D000818:Animals; D004706:Endodeoxyribonucleases / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D005786:Gene Expression Regulation; D006790:Host-Parasite Interactions; D006801:Humans; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D012549:Schistosoma japonicum / Q000201:enzymology* / Q000472:pathogenicity; D012554:Schistosomiasis japonica / Q000235:genetics* / Q000469:parasitology
chemical_list: D004706:Endodeoxyribonucleases; C019329:deoxyribonuclease II