Analysis of genetic variability within Argulus japonicus from representatives of Africa, Middle East, and Asia revealed by sequences of three mitochondrial DNA genes.
This study investigated the genetic variability within fish louse Argulus japonicus (Crustacea: Branchiura) from Africa, Middle East, and Asia by polymerase chain reaction in three mitochondrial DNA (mtDNA) regions, namely, cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunits 1 and 4 (nad1 and nad4). Six different sequences from a portion of the cox1 gene (pcox1) and a portion of the nad1 and nad4 genes (pnad1 and pnad4) for ten adult specimens from infected fish in China, Egypt, and Syria were amplified separately from individual and the amplicons were subjected to direct sequencing. A + T percentages were 68.8-69% for pcox1, 77.1-77.6% for pnad1, and 60.4-60.9% for pnad4. Among all the collected parasites, A. japonicus sequence variations were 0.0-1.9% for cox1, 0.0-2.3% for nad1, and 0.0-0.8% for nad4. In rivers, sequence variations among all individuals were 0.4-0.8% for cox1, 1.0-2.3% for nad1, and 0.4-0.8% for nad4, while sequence variations among all the collected parasites in fish farms were 0.6-1.9% for cox1, 0.0-1.7% for nad1, and 0.2-0.6% for nad4. The nad1 was the most variable gene among selected markers, while nad4 was a more conserved gene than cox1. All isolates of A. japonicus were sister to Argulus americanus in phylogenetic tree and they grouped together in one sub-clade, while isolates from China and Egypt fish farms were closely clustered together. However, moderate genetic drift and slight mutation could be observed among A. japonicus individuals. These findings demonstrated the convenience and attributes of the three selected mtDNA sequences for population genetic studies of A. japonicus where nad1 is a new and reliable marker to detect the sequence variation among A. japonicus individuals.
Wadeh
Hicham
H
College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, People's Republic of China.
Alsarakibi
Muhamd
M
Li
Guoqing
G
D000818:Animals; D033341:Arguloida / Q000145:classification / Q000235:genetics*; D002681:China; D004272:DNA, Mitochondrial / Q000235:genetics*; D004534:Egypt; D003576:Electron Transport Complex IV / Q000235:genetics*; D005393:Fish Diseases / Q000469:parasitology; D050259:Genes, Mitochondrial; D014644:Genetic Variation; D005828:Genetics, Population; D009245:NADH Dehydrogenase / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013593:Syria
D004272:DNA, Mitochondrial; D009245:NADH Dehydrogenase; D003576:Electron Transport Complex IV
Acta Vet Scand. 1995;36(3):283-98
7502946
Mol Cell Probes. 2005 Oct;19(5):306-13
16084062
Trends Parasitol. 2002 May;18(5):206-13
11983601
Vet Parasitol. 2009 May 26;162(1-2):67-74
19303214
Proc Biol Sci. 2004 Mar 7;271(1538):537-44
15129965
Mol Phylogenet Evol. 2004 Apr;31(1):178-91
15019618
Nature. 2010 Feb 25;463(7284):1079-83
20147900
Nucleic Acids Res. 1999 Apr 15;27(8):1767-80
10101183
Parasitol Res. 1998 Aug;84(8):676-81
9747941
Parasitol Res. 2008 Mar;102(4):765-70
18094998
Int J Parasitol. 1995 May;25(5):647-51
7635644
Nucleic Acids Res. 1997 Dec 15;25(24):4876-82
9396791
Int J Parasitol. 2000 Mar;30(3):283-90
10719121
BMC Evol Biol. 2009 May 27;9:119
19473484
Mol Biol Evol. 2000 Jul;17(7):1123-5
10889225
Arthropod Struct Dev. 2008 Jul;37(4):333-46
18394959
Proc Natl Acad Sci U S A. 2002 Feb 5;99(3):1426-30
11818548
Comput Appl Biosci. 1996 Aug;12(4):357-8
8902363