title: Gene discovery, evolutionary affinity and molecular detection of Oxyspirura petrowi, an eye worm parasite of game birds.
abstract: BACKGROUND
  Oxyspirura petrowi appears to be emerging as a nematode parasite that could negatively impact Northern Bobwhite quail individuals and populations within Texas and other regions of the United States. Despite this eye worm's potential importance in the conservation of wild quail, little is known about the general biology and genome composition of O. petrowi. To fill the knowledge gap, we performed a small scale random genome sequence survey, sequenced its 18S rRNA and the intergenic region between the 18S and 28S rRNA genes, studied its phylogenetic affinity, and developed a PCR protocol for the detection of this eye worm.
  
  
  RESULTS
  We have generated ~240 kb of genome sequence data derived from 348 clones by a random genome survey of an O. petrowi genomic library. The eye worm genome is AT-rich (i.e., 62.2% AT-content), and contains a high number of microsatellite sequences. The discovered genes encode a wide-range of proteins including hypothetical proteins, enzymes, nematode-specific proteins. Phylogenetic analysis based on 18S rRNA sequences indicate that the Spiruroidea is paraphyletic, in which Oxyspirura and its closely related species are sisters to the filarial nematodes. We have also developed a PCR protocol based on the ITS2 sequence that allows sensitive and specific detection of eye worm DNA in feces. Using this newly developed protocol, we have determined that ~28% to 33% of the fecal samples collected from Northern Bobwhites and Scaled Quail in Texas in the spring of 2013 are O. petrowi positive.
  
  
  CONCLUSIONS
  The O. petrowi genome is rich in microsatellite sequences that may be used in future genotyping and molecular fingerprinting analysis. This eye worm is evolutionarily close to the filarial nematodes, implying that therapeutic strategies for filariasis such as Loa loa would be referential in developing treatments for the Thelazoidea parasites. Our qPCR-based survey has confirmed that O. petrowi infection is of potential concern to quail managers in Texas.
authors.affiliation: Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA. xianglx@zju.edu.cn.
authors.forename: Lixin
authors.initials: L
authors.lastname: Xiang
authors.forename: Fengguang
authors.initials: F
authors.lastname: Guo
authors.forename: Haili
authors.initials: H
authors.lastname: Zhang
authors.forename: Lloyd
authors.initials: L
authors.lastname: LaCoste
authors.forename: Dale
authors.initials: D
authors.lastname: Rollins
authors.forename: Andrea
authors.initials: A
authors.lastname: Bruno
authors.forename: Alan M
authors.initials: AM
authors.lastname: Fedynich
authors.forename: Guan
authors.initials: G
authors.lastname: Zhu
mesh_terms: D000818:Animals; D001715:Bird Diseases / Q000469:parasitology*; D016000:Cluster Analysis; D003088:Colinus / Q000469:parasitology*; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D005128:Eye Diseases / Q000469:parasitology / Q000662:veterinary*; D008969:Molecular Sequence Data; D009349:Nematode Infections / Q000469:parasitology / Q000662:veterinary*; D010273:Parasitic Diseases, Animal / Q000469:parasitology*; D010274:Parasitology / Q000379:methods; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012339:RNA, Ribosomal, 28S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013781:Texas; D013802:Thelazioidea / Q000235:genetics* / Q000302:isolation & purification*; D014481:United States
chemical_list: D018509:DNA, Helminth; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012337:RNA, Ribosomal, 18S; D012339:RNA, Ribosomal, 28S