The Mitochondrial Genome of Baylisascaris procyonis
Yue Xie1, Zhihe Zhang2, Lili Niu3, Qiang Wang3, Chengdong Wang2, Jingchao Lan2,
Jiabo Deng3, YanFu1, Huaming Nie1, Ning Yan1, Deying Yang1, Guiying Hao1, Xiaobin Gu1, Shuxian Wang1, XuerongPeng4, Guangyou Yang1*
1 Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Ya’an, China,2 The Sichuan Key Laboratory for Conservation Biology on Endangered Wildlife – Developing Toward a State Key Laboratory for China, Chengdu Research Base of Giant Panda Breeding, Chengdu, Sichuan, China, 3 Chengdu Zoological Garden, Chengdu, Sichuan, China,4 Department of Chemistry, College of Life and Basic Science, Sichuan Agricultural University, Ya’an, China
Abstract
Background: Baylisascaris procyonis (Nematoda: Ascaridida), an intestinal nematode of raccoons, is emerging as an important helminthic zoonosis due to serious or fatal larval migrans in animals and humans. Despite its significant veterinary and public health impact, the epidemiology, molecular ecology and population genetics of this parasite remain largely unexplored. Mitochondrial (mt) genomes can provide a foundation for investigations in these areas and assist in the diagnosis and control ofB. procyonis . In this study, the first complete mt genome sequence of B. procyonis was determined using a polymerase chain reaction (PCR)-based primer-walking strategy.
Methodology/Principal Findings: The circular mt genome (14781 bp) of B. procyoniscontained 12 protein-coding, 22 transfer RNA and 2 ribosomal RNA genes congruent with other chromadorean nematodes. Interestingly, the B. procyonis mtDNA featured an extremely long AT-rich region (1375 bp) and a high number of intergenic spacers (17), making it unique compared with other secernentean nematodes characterized to date. Additionally, the entire genome displayed notable levels of AT skew and GC skew. Based on pairwise comparisons and sliding window analysis of mt genes among the available 11 Ascaridida mtDNAs, new primer pairs were designed to amplify specific short fragments of the genes cytb (548 bp fragment) and rrnL (200 bp fragment) in the B. procyonismtDNA, and tested as possible alternatives to existing mt molecular beacons for Ascaridida. Finally, phylogenetic analysis of mtDNAs provided novel estimates of the interrelationships of Baylisasaris and Ascaridida.
Conclusions/Significance:The complete mt genome sequence of B. procyonis sequenced here should contribute to molecular diagnostic methods, epidemiological investigations and ecological studies ofB. procyonisand other related ascaridoids. The information will be important in refining the phylogenetic relationships within the order Ascaridida and enriching the resource of markers for systematic, population genetic and evolutionary biological studies of parasitic nematodes of socio-economic importance.
Citation:Xie Y, Zhang Z, Niu L, Wang Q, Wang C, et al. (2011) The Mitochondrial Genome of Baylisascaris procyonis. PLoS ONE 6(10): e27066. doi:10.1371/ journal.pone.0027066
Editor:Justin David Brown, University of Georgia, United States of America
Received May 27, 2011; Accepted October 10, 2011; Published October 28, 2011
Copyright:[1] 2011 Xie et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding:This work was supported by grant from the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT) (grant no. IRT0848), the Research Fund (Project No. CPF2010-08) for the Chengdu Research of Giant Panda Breeding and the Special Funds for the Training of PhD Students from the Ministry of Education, China (grant no. 20095103110007). The funders had no role in study design, data collection and analysis, decision to publish,or preparation of the manuscript.
Competing Interests:The authors have declared that no competing interests exist.
* E-mail: guangyou1963@yahoo.com.cn
