http://informahealthcare.com/mdn ISSN: 1940-1736 (print), 1940-1744 (electronic) Mitochondrial DNA, Early Online: 1–3 ! 2015 Informa UK Ltd. DOI: 10.3109/19401736.2015.1007285
MITOGENOME ANNOUNCEMENT
The complete mitochondrial genome of Allocricetulus eversmanni (Rodentia: Cricetidae) Guangjie Luo and Jicheng Liao
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou, China Abstract
Keywords
Allocricetulus eversmanni is a unique species in the Allocricetulus, belonging to the Cricetinae group. Its complete mitochondrial genome was first obtained and the total length was 16,282 bp. Protein-coding genes approximately accounted for 69.6% of the complete genome. The heavy strand contained 30% A, 14.4% G, 27.9% C, 27.7% T. Compared with most other mammals, it had the same arrangement and similar length of vary genes or regions. The complete mitochondrial genome of A. eversmanni was conducive to more accurately locate its taxonomic status in Cricetinae and its evolutionary history. At the same time, it provided significant information about consummation of A. eversmanni gene pool.
Allocricetulus eversmanni, complete mitochondrial genome, unique species
Allocricetulus eversmanni is a unique species of the genus Allocricetulus, belonging to the Cricetinae group. Besides Allocricetulus, there are Cansumys, Cricetus, Cricetulus, Mesocricetus and Phodopus in Cricetinae. In China, A. eversmanni mainly spreads in some azonality habitats of desert steppe. It had the activities of the radius of 200 m and often invaded other rat holes as its own living hole (Li et al., 1994). In most mammals mitochondrial DNA (mtDNA) is approximately 16.5 kb, it exists and replicates independently in the mitochondrion (Partridge et al., 2007). The sequences of mtDNA in most mammals encode 13 proteins, 2 ribosomal RNAs (rRNA) and 22 transfer RNAs (tRNA). With many complete mitochondrial genome being reported, they have been widely used in the study of phylogeography and systematics, phylogenetic relationships, molecular evolution and population genetics among the most mammals (Martin et al., 2000; Partridge et al., 2007; Triant & DeWoody, 2006). Nowadays, mitochondrion has increasing connection with health biology. During last two decades, the evidence provided that mitochondrion plays an important role in vary physiological conditions and diseases (Singh et al., 2014). An increasing number of epigenetic diseases and mitochondrial disorders have been connected with mitochondrial dysfunction (Singh et al., 2014; Wallace & Fan, 2010). Hence, as the first step, the obtained mitochondrial genome appeared significant. So far we have found only three genes of A. eversmanni: there are 12 SrRNA, cyt-b and vwf. In this study, we got its complete
Correspondence: Jicheng Liao, Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou 730000, China. Tel: +86 13919484992. E-mail: [email protected]
History Received 5 December 2014 Revised 24 December 2014 Accepted 30 December 2014 Published online 13 March 2015
mitochondrial genome, it will provide significant information about consummation of A. eversmanni gene pool. We extracted total genomic DNA with TIANamp Genomic DNA Kit from the muscle sample of A. eversmanni, then amplified DNA with 50 ml reaction system which contained 5 ml 10 PCR buffer (with Mg2+), 1 ml dNTP (10 mM each), 2 ml of each primer (10 mM each), 1 ml Pfu Polymerase (5 U/ml), 3 ml total genomic DNA (100 ng–200 ng) as the template and 36 ml water. PCR was run with pre-denaturation for 5 min at 95 C, followed by 32 cycles of denaturation for 40 s at 95 C, annealing for 50 s at 53–60 C, extension for 1.5–5 min at 72 C, then a final extension at 72 C for 10 min. The primer pairs used are shown in Table 1. The complete mitochondrial sequence of A. eversmanni is 16,282 bp and it is accessible at GenBank (Accession No.KP231506) (Table 2). We used MEGA6.0 (Tamura et al., 2013) and analyzed the overall base composition of heavy strand, it contained 30% A, 14.4% G, 27.9% C, 27.7% T. The total length of protein-coding sequences was 11,337 bp, approximately accounting for 69.6% of the complete genome. ATG is the initiation codon for all the protein-coding genes except for ND1, ND2, ND3 and ND5. By the same token, as the termination codon, TAA arranges the end of the most protein-coding genes, and incomplete termination codon T is used for the genes ND1, ND2, Cox1, Cox2 and Cox3. The gene ND4 ends with stop codon TAG. The heavy strand is conducted template for all the protein-coding genes but ND6 is encoded on the light strand. In Rodentia, the complete genome of one species was conducive to more accurately locate its taxonomic status and its evolutionary history than that with partial sequences of mtDNA (Neumann et al., 2005; Norris et al., 2004). Therefore, in order to exactly introduce some questions about Rodentia, the obtained complete mitochondrial genome of the research object was necessary.
2
G. Luo & J. Liao
Mitochondrial DNA, Early Online: 1–3
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Table 1. Primer pairs used for amplification and sequencing of the complete mitochondrial genome of Allocricetulus eversmanni. Name of primer
Sequence of primer (50 -30 )
Reference
L14841-F HCRIC3-R PL1-F PL1-R CK(12SrRNA)-F CK(12SrRNA)-R PL2-F PL2-R PL3-F PL3-R Gln-F ND2-R CK(ND2)-F CK(COX1)-R PL6-F PL6-R ATP6-F Arg-R PL8-F PL8-R PL10-F PL10-R Ser-F Cytb-R
AAAAAGCTTCCATCCAACATCTCAGCATGATGAAA GATGAAAGGGTATTCTACTGGTTG TTCCCCTTAAATAAGACATCTCG CGCCAAGTCCTTTGAGTTTTA AGCCCAAGGAGACGGTATCA CTGGATTAGCAAGGGGTGGT GGATTAGATACCCCACTATGCTT ATAGATAGAAACCGACCTGGA CCTCGATGTTGGATCAGG GTATGGGCCCGATAGCTT CCGCCTGTTCTTATGAATCCG GCTTTGAAGCTCTTGGACTGTGCT ACACTAATAGCCATCACAGCCC ATCTGGGTAGTCGGAGTAACG CTGGCTTTGTCCACTGATTCC GATTACGGCTCCAGCTCATAG ATTATGACAACCTCAAAACACCTGG TAAATACTGTGGATGGCATGCTGGT GAACACAAAAAGGCTTAGAATGAACAG GGTTCCTAAGACCAACGGATTACTC TGCTACACCAACGCCTGAG AGTCACAGCATCCCGAAAA CCATCCCATACACGAGAACTAACGC TCAGCCGTAGTTACGTCTCGACAG
Kocher et al., 1989 Neumann et al., 2005 Hao et al., 2011 Hao et al., 2011 Kang et al., 2014 Kang et al., 2014 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 In this study In this study Kang et al., 2014 Kang et al., 2014 Hao et al., 2011 Hao et al., 2011 In this study In this study Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 In this study In this study
Acknowledgements
Table 2. Allocricetulus eversmanni mitochondrial genome*. Position Gene
From
To
tRNA-Phe 12SrRNA tRNA-Val 16SrRNA tRNA-Leu(UUR) NADH1 tRNA-Ile tRNA-Gln tRNA-Met NADH2 tRNA-Trp tRNA-Ala tRNA-Asn tRNA-Cys tRNA-Tyr COX1 tRNA-Ser(UCN) tRNA-Asp COX2 tRNA-Lys ATP8 ATP6 COX3 tRNA-Gly NADH3 tRNA-Arg NADH4L NADH4 tRNA-His tRNA-Ser(AGY) tRNA-Leu(CUN) NADH5 NADH6 tRNA-Glu Cyt-b tRNA-Thr tRNA-Pro D-loop
1 68 1019 1097 2663 2738 3693 3759 3834 3903 4936 5006 5078 5180 5247 5315 6860 6932 7001 7689 7755 7916 8596 9380 9448 9799 9868 10,158 11,541 11,604 11,662 11,732 13,539 14,064 14,137 15,280 15,352 15,417
66 1017 1090 2661 2737 3692 3761 3829 3902 4935 5003 5075 5148 5247 5312 6857 6928 6999 7685 7753 7958 8596 9379 9447 9795 9867 10,164 11,540 11,603 11,661 11,731 13,555 14,063 14,132 15,279 15,347 15,418 16,282
We are grateful to LM Zhao and QS Zhao, of School of Life Sciences, Lanzhou University, who helped in the process of sampling.
Codon Size (bp) Initiation Termination Strand 66 950 72 1565 75 955 69 71 69 1033 68 70 71 68 66 1543 69 68 685 65 204 681 784 68 348 69 297 1383 63 58 70 1824 525 69 1143 68 67 866
GTG
T– –
ATT
T– –
ATG
T– –
ATG
T– –
ATG ATG ATG
TAA TAA T– –
ATT
TAA
ATG ATG
TAA TAG
ATT ATG
TAA TAA
ATG
TAA
*The entire sequence begins at the first of tRNA-Phe from 50 to 30 .
H H H H H H H L H H H L L L L H H H H H H H H H H H H H H H H H L L H H H H
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. The work was supported by the National Natural Science Foundation of China (Nos. 30770301, 30870294).
References Hao HB, Liu SY, Zhang XY, Chen WC, Song ZB, Peng HY, Liu Y, Yue BS. (2011). Complete mitochondrial genome of a new vole Proedromys liangshanensis (Rodentia: Cricetidae) and phylogenetic analysis with related species: Are there implications for the validity of the genus Proedromys? Mitochondrial DNA 22:28–34. Kang CL, Yue H, Liu MY, Huang T, Liu Y, Zhang XY, Yue BS, et al. (2014). The complete mitochondrial genome of Cricetulus kamensis (Rodentia: Cricetidae). Mitochondrial DNA 1–2. [Epub ahead of print]. Kocher TD, Thomas WK, Meyer A, Edwards SV, Paabo S, Villablanca FX, Wilson AC. (1989). Dynamics of mitochondrial DNA evolution in animals: Amplification and sequencing with conserved primers. Proc Natl Acad Sci USA 86:6196–200. Li XM, Duan QH, Zhao TB, Wang Q. (1994). The study of the trunk and four limbs of Allocricetulus eversmanni. Inner Mongol Endem Dis Res 19:71–3. Martin Y, Gerlach G, Schlotterer C, Meyer A. (2000). Molecular phylogeny of European muroid rodents based on complete cytochrome b sequences. Mol Phylogenet Evol 16:37–47. Neumann K, Michaux JR, Maak S, Jansman HAH, Kayser A, Mundt G, Gattermann R. (2005). Genetic spatial structure of European common hamsters (Cricetus cricetus) – A result of repeated range expansion and demographic bottlenecks. Mol Ecol 14:1473–83. Norris RW, Zhou KY, Zhou CQ, Yang G, Kilpatrick CW, Honeycutt RL. (2004). The phylogenetic position of the zokors (Myospalacinae) and comments on the families of muroids (Rodentia). Mol Phylogenet Evol 31:972–8. Partridge MA, Davidson MM, Hei TK. (2007). The complete nucleotide sequence of Chinese hamster (Cricetulus griseus) mitochondrial DNA. DNA Seq 18:341–6.
DOI: 10.3109/19401736.2015.1007285
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Singh RP, Thangaraj K, Kale RK. (2014). Mitochondria in health and disease. Mitochondrion 16:1. Tamura K, Stecher G, Peterson D, Filipski A, Kumar S. (2013). MEGA6: Molecular evolutionary genetics analysis version 6.0. Mol Biol Evol 30:2725–9.
Mitgenome of Allocricetulus eversmanni
3
Triant DA, DeWoody JA. (2006). Accelerated molecular evolution in Microtus (Rodentia) as assessed via complete mitochondrial genome sequences. Genetica 128:95–108. Wallace DC, Fan W. (2010). Energetics, epigenetics, mitochondrial genetics. Mitochondrion 10:12–31.
MITOGENOME ANNOUNCEMENT
The complete mitochondrial genome of Allocricetulus eversmanni (Rodentia: Cricetidae) Guangjie Luo and Jicheng Liao
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou, China Abstract
Keywords
Allocricetulus eversmanni is a unique species in the Allocricetulus, belonging to the Cricetinae group. Its complete mitochondrial genome was first obtained and the total length was 16,282 bp. Protein-coding genes approximately accounted for 69.6% of the complete genome. The heavy strand contained 30% A, 14.4% G, 27.9% C, 27.7% T. Compared with most other mammals, it had the same arrangement and similar length of vary genes or regions. The complete mitochondrial genome of A. eversmanni was conducive to more accurately locate its taxonomic status in Cricetinae and its evolutionary history. At the same time, it provided significant information about consummation of A. eversmanni gene pool.
Allocricetulus eversmanni, complete mitochondrial genome, unique species
Allocricetulus eversmanni is a unique species of the genus Allocricetulus, belonging to the Cricetinae group. Besides Allocricetulus, there are Cansumys, Cricetus, Cricetulus, Mesocricetus and Phodopus in Cricetinae. In China, A. eversmanni mainly spreads in some azonality habitats of desert steppe. It had the activities of the radius of 200 m and often invaded other rat holes as its own living hole (Li et al., 1994). In most mammals mitochondrial DNA (mtDNA) is approximately 16.5 kb, it exists and replicates independently in the mitochondrion (Partridge et al., 2007). The sequences of mtDNA in most mammals encode 13 proteins, 2 ribosomal RNAs (rRNA) and 22 transfer RNAs (tRNA). With many complete mitochondrial genome being reported, they have been widely used in the study of phylogeography and systematics, phylogenetic relationships, molecular evolution and population genetics among the most mammals (Martin et al., 2000; Partridge et al., 2007; Triant & DeWoody, 2006). Nowadays, mitochondrion has increasing connection with health biology. During last two decades, the evidence provided that mitochondrion plays an important role in vary physiological conditions and diseases (Singh et al., 2014). An increasing number of epigenetic diseases and mitochondrial disorders have been connected with mitochondrial dysfunction (Singh et al., 2014; Wallace & Fan, 2010). Hence, as the first step, the obtained mitochondrial genome appeared significant. So far we have found only three genes of A. eversmanni: there are 12 SrRNA, cyt-b and vwf. In this study, we got its complete
Correspondence: Jicheng Liao, Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, School of Life Sciences, Lanzhou University, Lanzhou 730000, China. Tel: +86 13919484992. E-mail: [email protected]
History Received 5 December 2014 Revised 24 December 2014 Accepted 30 December 2014 Published online 13 March 2015
mitochondrial genome, it will provide significant information about consummation of A. eversmanni gene pool. We extracted total genomic DNA with TIANamp Genomic DNA Kit from the muscle sample of A. eversmanni, then amplified DNA with 50 ml reaction system which contained 5 ml 10 PCR buffer (with Mg2+), 1 ml dNTP (10 mM each), 2 ml of each primer (10 mM each), 1 ml Pfu Polymerase (5 U/ml), 3 ml total genomic DNA (100 ng–200 ng) as the template and 36 ml water. PCR was run with pre-denaturation for 5 min at 95 C, followed by 32 cycles of denaturation for 40 s at 95 C, annealing for 50 s at 53–60 C, extension for 1.5–5 min at 72 C, then a final extension at 72 C for 10 min. The primer pairs used are shown in Table 1. The complete mitochondrial sequence of A. eversmanni is 16,282 bp and it is accessible at GenBank (Accession No.KP231506) (Table 2). We used MEGA6.0 (Tamura et al., 2013) and analyzed the overall base composition of heavy strand, it contained 30% A, 14.4% G, 27.9% C, 27.7% T. The total length of protein-coding sequences was 11,337 bp, approximately accounting for 69.6% of the complete genome. ATG is the initiation codon for all the protein-coding genes except for ND1, ND2, ND3 and ND5. By the same token, as the termination codon, TAA arranges the end of the most protein-coding genes, and incomplete termination codon T is used for the genes ND1, ND2, Cox1, Cox2 and Cox3. The gene ND4 ends with stop codon TAG. The heavy strand is conducted template for all the protein-coding genes but ND6 is encoded on the light strand. In Rodentia, the complete genome of one species was conducive to more accurately locate its taxonomic status and its evolutionary history than that with partial sequences of mtDNA (Neumann et al., 2005; Norris et al., 2004). Therefore, in order to exactly introduce some questions about Rodentia, the obtained complete mitochondrial genome of the research object was necessary.
2
G. Luo & J. Liao
Mitochondrial DNA, Early Online: 1–3
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Table 1. Primer pairs used for amplification and sequencing of the complete mitochondrial genome of Allocricetulus eversmanni. Name of primer
Sequence of primer (50 -30 )
Reference
L14841-F HCRIC3-R PL1-F PL1-R CK(12SrRNA)-F CK(12SrRNA)-R PL2-F PL2-R PL3-F PL3-R Gln-F ND2-R CK(ND2)-F CK(COX1)-R PL6-F PL6-R ATP6-F Arg-R PL8-F PL8-R PL10-F PL10-R Ser-F Cytb-R
AAAAAGCTTCCATCCAACATCTCAGCATGATGAAA GATGAAAGGGTATTCTACTGGTTG TTCCCCTTAAATAAGACATCTCG CGCCAAGTCCTTTGAGTTTTA AGCCCAAGGAGACGGTATCA CTGGATTAGCAAGGGGTGGT GGATTAGATACCCCACTATGCTT ATAGATAGAAACCGACCTGGA CCTCGATGTTGGATCAGG GTATGGGCCCGATAGCTT CCGCCTGTTCTTATGAATCCG GCTTTGAAGCTCTTGGACTGTGCT ACACTAATAGCCATCACAGCCC ATCTGGGTAGTCGGAGTAACG CTGGCTTTGTCCACTGATTCC GATTACGGCTCCAGCTCATAG ATTATGACAACCTCAAAACACCTGG TAAATACTGTGGATGGCATGCTGGT GAACACAAAAAGGCTTAGAATGAACAG GGTTCCTAAGACCAACGGATTACTC TGCTACACCAACGCCTGAG AGTCACAGCATCCCGAAAA CCATCCCATACACGAGAACTAACGC TCAGCCGTAGTTACGTCTCGACAG
Kocher et al., 1989 Neumann et al., 2005 Hao et al., 2011 Hao et al., 2011 Kang et al., 2014 Kang et al., 2014 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 In this study In this study Kang et al., 2014 Kang et al., 2014 Hao et al., 2011 Hao et al., 2011 In this study In this study Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 Hao et al., 2011 In this study In this study
Acknowledgements
Table 2. Allocricetulus eversmanni mitochondrial genome*. Position Gene
From
To
tRNA-Phe 12SrRNA tRNA-Val 16SrRNA tRNA-Leu(UUR) NADH1 tRNA-Ile tRNA-Gln tRNA-Met NADH2 tRNA-Trp tRNA-Ala tRNA-Asn tRNA-Cys tRNA-Tyr COX1 tRNA-Ser(UCN) tRNA-Asp COX2 tRNA-Lys ATP8 ATP6 COX3 tRNA-Gly NADH3 tRNA-Arg NADH4L NADH4 tRNA-His tRNA-Ser(AGY) tRNA-Leu(CUN) NADH5 NADH6 tRNA-Glu Cyt-b tRNA-Thr tRNA-Pro D-loop
1 68 1019 1097 2663 2738 3693 3759 3834 3903 4936 5006 5078 5180 5247 5315 6860 6932 7001 7689 7755 7916 8596 9380 9448 9799 9868 10,158 11,541 11,604 11,662 11,732 13,539 14,064 14,137 15,280 15,352 15,417
66 1017 1090 2661 2737 3692 3761 3829 3902 4935 5003 5075 5148 5247 5312 6857 6928 6999 7685 7753 7958 8596 9379 9447 9795 9867 10,164 11,540 11,603 11,661 11,731 13,555 14,063 14,132 15,279 15,347 15,418 16,282
We are grateful to LM Zhao and QS Zhao, of School of Life Sciences, Lanzhou University, who helped in the process of sampling.
Codon Size (bp) Initiation Termination Strand 66 950 72 1565 75 955 69 71 69 1033 68 70 71 68 66 1543 69 68 685 65 204 681 784 68 348 69 297 1383 63 58 70 1824 525 69 1143 68 67 866
GTG
T– –
ATT
T– –
ATG
T– –
ATG
T– –
ATG ATG ATG
TAA TAA T– –
ATT
TAA
ATG ATG
TAA TAG
ATT ATG
TAA TAA
ATG
TAA
*The entire sequence begins at the first of tRNA-Phe from 50 to 30 .
H H H H H H H L H H H L L L L H H H H H H H H H H H H H H H H H L L H H H H
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. The work was supported by the National Natural Science Foundation of China (Nos. 30770301, 30870294).
References Hao HB, Liu SY, Zhang XY, Chen WC, Song ZB, Peng HY, Liu Y, Yue BS. (2011). Complete mitochondrial genome of a new vole Proedromys liangshanensis (Rodentia: Cricetidae) and phylogenetic analysis with related species: Are there implications for the validity of the genus Proedromys? Mitochondrial DNA 22:28–34. Kang CL, Yue H, Liu MY, Huang T, Liu Y, Zhang XY, Yue BS, et al. (2014). The complete mitochondrial genome of Cricetulus kamensis (Rodentia: Cricetidae). Mitochondrial DNA 1–2. [Epub ahead of print]. Kocher TD, Thomas WK, Meyer A, Edwards SV, Paabo S, Villablanca FX, Wilson AC. (1989). Dynamics of mitochondrial DNA evolution in animals: Amplification and sequencing with conserved primers. Proc Natl Acad Sci USA 86:6196–200. Li XM, Duan QH, Zhao TB, Wang Q. (1994). The study of the trunk and four limbs of Allocricetulus eversmanni. Inner Mongol Endem Dis Res 19:71–3. Martin Y, Gerlach G, Schlotterer C, Meyer A. (2000). Molecular phylogeny of European muroid rodents based on complete cytochrome b sequences. Mol Phylogenet Evol 16:37–47. Neumann K, Michaux JR, Maak S, Jansman HAH, Kayser A, Mundt G, Gattermann R. (2005). Genetic spatial structure of European common hamsters (Cricetus cricetus) – A result of repeated range expansion and demographic bottlenecks. Mol Ecol 14:1473–83. Norris RW, Zhou KY, Zhou CQ, Yang G, Kilpatrick CW, Honeycutt RL. (2004). The phylogenetic position of the zokors (Myospalacinae) and comments on the families of muroids (Rodentia). Mol Phylogenet Evol 31:972–8. Partridge MA, Davidson MM, Hei TK. (2007). The complete nucleotide sequence of Chinese hamster (Cricetulus griseus) mitochondrial DNA. DNA Seq 18:341–6.
DOI: 10.3109/19401736.2015.1007285
Mitochondrial DNA Downloaded from informahealthcare.com by RMIT University on 03/15/15 For personal use only.
Singh RP, Thangaraj K, Kale RK. (2014). Mitochondria in health and disease. Mitochondrion 16:1. Tamura K, Stecher G, Peterson D, Filipski A, Kumar S. (2013). MEGA6: Molecular evolutionary genetics analysis version 6.0. Mol Biol Evol 30:2725–9.
Mitgenome of Allocricetulus eversmanni
3
Triant DA, DeWoody JA. (2006). Accelerated molecular evolution in Microtus (Rodentia) as assessed via complete mitochondrial genome sequences. Genetica 128:95–108. Wallace DC, Fan W. (2010). Energetics, epigenetics, mitochondrial genetics. Mitochondrion 10:12–31.
