Limits...
The mitochondrial genome of the chimpanzee louse, Pediculus schaeffi: insights into the process of mitochondrial genome fragmentation in the blood-sucking lice of great apes.

Herd KE, Barker SC, Shao R - BMC Genomics (2015)

Bottom Line: The head louse, Pediculus capitis, and the body louse, Pe. humanus, have their 37 mt genes on 20 minichromosomes.The pubic louse, Pthirus pubis, has its 34 mt genes known on 14 minichromosomes.Our results provide insights into the process of mt genome fragmentation in the sucking lice in a relatively fine evolutionary scale.

View Article: PubMed Central - PubMed

Affiliation: Department of Parasitology, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia. kate.herd@uqconnect.edu.au.

ABSTRACT

Background: Blood-sucking lice in the genera Pediculus and Pthirus are obligate ectoparasites of great apes. Unlike most bilateral animals, which have 37 mitochondrial (mt) genes on a single circular chromosome, the sucking lice of humans have extensively fragmented mt genomes. The head louse, Pediculus capitis, and the body louse, Pe. humanus, have their 37 mt genes on 20 minichromosomes. The pubic louse, Pthirus pubis, has its 34 mt genes known on 14 minichromosomes. To understand the process of mt genome fragmentation in the sucking lice of great apes, we sequenced the mt genome of the chimpanzee louse, Pe. schaeffi, and compared it with the three human lice.

Results: We identified all of the 37 mt genes typical of bilateral animals in the chimpanzee louse; these genes are on 18 types of minichromosomes. Seventeen of the 18 minichromosomes of the chimpanzee louse have the same gene content and gene arrangement as their counterparts in the human head louse and the human body louse. However, five genes, cob, trnS 1 , trnN, trnE and trnM, which are on three minichromosomes in the human head louse and the human body louse, are together on one minichromosome in the chimpanzee louse.

Conclusions: Using the human pubic louse, Pt. pubis, as an outgroup for comparison, we infer that a single minichromosome has fragmented into three in the lineage leading to the human head louse and the human body louse since this lineage diverged from the chimpanzee louse ~6 million years ago. Our results provide insights into the process of mt genome fragmentation in the sucking lice in a relatively fine evolutionary scale.

No MeSH data available.


Related in: MedlinePlus

Recombination hot-spots in the mitochondrial genomes of the chimpanzee louse, Pediculus schaeffi, indicated by shared identical sequences between non-homologous genes. a: locations of shared identical sequences in genes. Shared identical sequences are highlighted in color with their length in bp. Genes are indicated with boxes from 5′ end to 3′ end. b: the 56-bp identical sequence shared between atp8 and cob used different open reading frames
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4557858&req=5

Fig2: Recombination hot-spots in the mitochondrial genomes of the chimpanzee louse, Pediculus schaeffi, indicated by shared identical sequences between non-homologous genes. a: locations of shared identical sequences in genes. Shared identical sequences are highlighted in color with their length in bp. Genes are indicated with boxes from 5′ end to 3′ end. b: the 56-bp identical sequence shared between atp8 and cob used different open reading frames

Mentions: Seven stretches of identical nucleotide sequences, 31 to 133 bp long, were found between five pairs of mt genes in the chimpanzee louse (Table 2). As in the three human lice [19], trnL1 and trnL2 of the chimpanzee louse differ by only one nucleotide at the third anticodon position, and thus share two stretches of identical sequences, 32 and 34 bp respectively (Fig. 2a; Additional file 4). nad5 and rrnL share 101-bp identical sequence in the chimpanzee louse; these two genes share 99-bp identical sequence in the human head louse and the human body louse, but not in the human pubic louse [19], nor in other blood-sucking lice [27]. cox1 and nad3 share 49 bp of identical sequence in the chimpanzee louse; these two genes, however, do not share longer-than-expected identical sequences in the human lice, nor in other sucking lice. atp8 and cob share 26 bp of identical sequence in the human head and body lice but share 54 bp of identical sequence in the chimpanzee louse. nad4 and nad5 share two stretches of identical sequences, 31 and 133 bp long, in the chimpanzee louse; in the human head louse and body louse, these two genes share 30 and 127 bp identical sequences.Table 1


The mitochondrial genome of the chimpanzee louse, Pediculus schaeffi: insights into the process of mitochondrial genome fragmentation in the blood-sucking lice of great apes.

Herd KE, Barker SC, Shao R - BMC Genomics (2015)

Recombination hot-spots in the mitochondrial genomes of the chimpanzee louse, Pediculus schaeffi, indicated by shared identical sequences between non-homologous genes. a: locations of shared identical sequences in genes. Shared identical sequences are highlighted in color with their length in bp. Genes are indicated with boxes from 5′ end to 3′ end. b: the 56-bp identical sequence shared between atp8 and cob used different open reading frames
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4557858&req=5

Fig2: Recombination hot-spots in the mitochondrial genomes of the chimpanzee louse, Pediculus schaeffi, indicated by shared identical sequences between non-homologous genes. a: locations of shared identical sequences in genes. Shared identical sequences are highlighted in color with their length in bp. Genes are indicated with boxes from 5′ end to 3′ end. b: the 56-bp identical sequence shared between atp8 and cob used different open reading frames
Mentions: Seven stretches of identical nucleotide sequences, 31 to 133 bp long, were found between five pairs of mt genes in the chimpanzee louse (Table 2). As in the three human lice [19], trnL1 and trnL2 of the chimpanzee louse differ by only one nucleotide at the third anticodon position, and thus share two stretches of identical sequences, 32 and 34 bp respectively (Fig. 2a; Additional file 4). nad5 and rrnL share 101-bp identical sequence in the chimpanzee louse; these two genes share 99-bp identical sequence in the human head louse and the human body louse, but not in the human pubic louse [19], nor in other blood-sucking lice [27]. cox1 and nad3 share 49 bp of identical sequence in the chimpanzee louse; these two genes, however, do not share longer-than-expected identical sequences in the human lice, nor in other sucking lice. atp8 and cob share 26 bp of identical sequence in the human head and body lice but share 54 bp of identical sequence in the chimpanzee louse. nad4 and nad5 share two stretches of identical sequences, 31 and 133 bp long, in the chimpanzee louse; in the human head louse and body louse, these two genes share 30 and 127 bp identical sequences.Table 1

Bottom Line: The head louse, Pediculus capitis, and the body louse, Pe. humanus, have their 37 mt genes on 20 minichromosomes.The pubic louse, Pthirus pubis, has its 34 mt genes known on 14 minichromosomes.Our results provide insights into the process of mt genome fragmentation in the sucking lice in a relatively fine evolutionary scale.

View Article: PubMed Central - PubMed

Affiliation: Department of Parasitology, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia. kate.herd@uqconnect.edu.au.

ABSTRACT

Background: Blood-sucking lice in the genera Pediculus and Pthirus are obligate ectoparasites of great apes. Unlike most bilateral animals, which have 37 mitochondrial (mt) genes on a single circular chromosome, the sucking lice of humans have extensively fragmented mt genomes. The head louse, Pediculus capitis, and the body louse, Pe. humanus, have their 37 mt genes on 20 minichromosomes. The pubic louse, Pthirus pubis, has its 34 mt genes known on 14 minichromosomes. To understand the process of mt genome fragmentation in the sucking lice of great apes, we sequenced the mt genome of the chimpanzee louse, Pe. schaeffi, and compared it with the three human lice.

Results: We identified all of the 37 mt genes typical of bilateral animals in the chimpanzee louse; these genes are on 18 types of minichromosomes. Seventeen of the 18 minichromosomes of the chimpanzee louse have the same gene content and gene arrangement as their counterparts in the human head louse and the human body louse. However, five genes, cob, trnS 1 , trnN, trnE and trnM, which are on three minichromosomes in the human head louse and the human body louse, are together on one minichromosome in the chimpanzee louse.

Conclusions: Using the human pubic louse, Pt. pubis, as an outgroup for comparison, we infer that a single minichromosome has fragmented into three in the lineage leading to the human head louse and the human body louse since this lineage diverged from the chimpanzee louse ~6 million years ago. Our results provide insights into the process of mt genome fragmentation in the sucking lice in a relatively fine evolutionary scale.

No MeSH data available.


Related in: MedlinePlus