Major Non-coding Region Research Articles

The complete mitochondrial genome of the drill (Mandrillus leucophaeus)

The drill (Mandrillus leucophaeus) is a primate of the family Cercopithecidae (Old World monkeys). Drills are among Africa’s most endangered mammals, and are listed by the IUCN as the highest conservation priority of all African primates and are used as a model for cytomegalovirus vaccine and antiviral development. Here, we describe the complete mitochondrial genome (mitogenome) sequence of M. leucophaeus. The genome is 16 547 bp in length, comprising 13 protein-coding genes, 22 tRNAs, 2 rRNAs and a major non-coding region. The gene content and order is in accord with the common vertebrate form. All PCGs share the start codon ATG except ND2(ATC), ND3(ATT) and ND5(ATA). ND1, ND2 and ATP8 use ATG as the end codon. COX1, COX2, ATP6, ND4L and ND5 employ ATT as the end codon. The other five PCGs share the end codon T––. Phylogenic tree was constructed based on the complete mitogenome of M. leucophaeus and 12 closely related species to estimate their phylogenic relationship. We present an important genetic resource for the family Cercopithecidae in general

Complete mitochondrial genome and phylogenetic relationship analyses of Amphioctopus aegina (Gray, 1849) (Cephalopoda: Octopodidae)

In this paper, the circular mitochondrial genome of Amphioctopus aegina (Cephalopoda: Octopodidae) was sequenced. The whole mitogenome of A. aegina was 15 545 base pairs (bp) in length with a base composition of 42.53% A, 33.26% T, 16.70% C, and 7.51% G. The complete mitogenome contained 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA genes, and a major non-coding region. The gene arrangements of A. aegina showed remarkable similarity to other Octopodidae species reported. The phylogenetic relationships were reconstructed with the concatenated sequences of the 13 PCGs of the mitochondrial genome, and illustrated that A. aegina had the closest genetic relatives to A. fangsiao.

Phylogenetic study of Ameiurus melas based on complete mitochondrial DNA sequence

In our research, 16 sets of primers were used to amplify contiguous, overlapping segments of the complete mitochondrial DNA (mtDNA) of Ameiurus melas. The total length of the mitochondrial genome is 16 512 bp and deposited in the GenBank with accession no. KT804702. The gene arrangement and transcriptional direction were similar to other bony fishes which contained 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNAs) and a major non-coding control region. The G contents were lowest (17.36%) and the nucleotide skewness for the coding strands of A. melas (GC-skew = −0.24) is biased toward G and the negative GC-skew ranges from −0.44 (ND6) to −0.13 (CO1). The phylogenetic studies indicate that A. melas and the Ictalurus punctatus are cluster together, they are sister group. However, the phylogenetic relationship of other Cyprininae has some differences, such as Pangasianodon gigas and Silurus asotus, which need further research.

The complete mitochondrial genome of Colobus angolensis palliatus

Colobus angolensis palliatus (C.a. palliatus), known as the angolan black-and-white colobus monkey, is an Old World monkey, belonging to the Colobus genus. It is a subspecies of C. angolensis. Here, we describe the complete mitochondrial genome (mitogenome) sequence of C.a. palliatus. The genome is 16 850 bp in length, comprising 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a major non-coding region. Phylogenic tree was constructed based on the complete mitogenome of C.a. palliatus and closely related 13 colobinae species to estimate their phylogenic relationship. We present an important genetic resource for the black-and-white colobus monkeys.

The complete sequence of mitochondrial genome of Wuzhishan pig (Sus Scrofa)

In the present study, we sequenced the complete mitochondrial genome of Wuzhishan pig, which was 16 741 bp in size and had a nucleotide composition in A and T (60.46%). The genome consisted of a major non-coding control region (D-loop region) and 37 genes, including 2 ribosomal RNA (rRNA) genes, 13 protein-coding genes (PCGs), and 22 transfer RNA (tRNA) genes. The genes in the mitochondrial genomes of Wuzhishan pig used three kinds of initiation codons (ATA, ATG, and GTG) and four kinds of termination codons (TAA, AGA, TAG, and an incomplete termination codons T–). The complete mitochondrial genome sequence of Wuzhishan pig provides an important data set for further study on genetic mechanism.

The complete mitochondrial genome and phylogenic analysis of Pseudobagrus vachelli

The complete mitochondrial genome of Pseudobagrus vachelli has been sequenced. The mitochondrial genome is 16 529 bp in length, with the base composition of 31.61% A, 26.88% T, 26.55% C, and 14.96% G, containing 2 ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes and a major non-coding control region (D-loop region). The gene order and orientation are similar with some typical fish species. The data will provide useful molecular information for phylogenetic studies concerning P. vachelli and its related species.

The complete mitochondrial genome of Brachymystax lenok tsinlingensis (Salmoninae, Salmonidae) and its intraspecific variation

The Manchurian trout, Brachymystax lenok tsinlingensis, is endangered in Korea, where the southern range limit for this cold-freshwater fish occurs. In this study, the complete mitochondrial genome of Korean B. lenok tsinlingensis was sequenced and its genetic characteristics were identified. The mitogenome of B. lenok tsinlingensis comprises 16,748 base pairs containing 37 genes (13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes) and one major non-coding region (control region), making it similar to the majority of vertebrate mitogenomes. Interestingly, at the base of the stem region of OL in B. lenok tsinlingensis, the conserved motif is replaced by a 5′-ACCGG-3′ motif instead of the 5′-GCCGG-3′. We also identified an 81-base-pair tandem-repeat motif in the control region, the length of which is reduced by one nucleotide compared to those in B. lenok and Hucho species. The number of repeat motifs differed between Korean and Chinese B. lenok tsinlingensis, with two and three reiterations, respectively. The control region of B. lenok and its relatives will be used as a genetic marker in evolution/genetic studies and as a PCR-based marker for rapid identification of their lineages.

Primer retention owing to the absence of RNase H1 is catastrophic for mitochondrial DNA replication

Encoding ribonuclease H1 (RNase H1) degrades RNA hybridized to DNA, and its function is essential for mitochondrial DNA maintenance in the developing mouse. Here we define the role of RNase H1 in mitochondrial DNA replication. Analysis of replicating mitochondrial DNA in embryonic fibroblasts lacking RNase H1 reveals retention of three primers in the major noncoding region (NCR) and one at the prominent lagging-strand initiation site termed Ori-L. Primer retention does not lead immediately to depletion, as the persistent RNA is fully incorporated in mitochondrial DNA. However, the retained primers present an obstacle to the mitochondrial DNA polymerase γ in subsequent rounds of replication and lead to the catastrophic generation of a double-strand break at the origin when the resulting gapped molecules are copied. Hence, the essential role of RNase H1 in mitochondrial DNA replication is the removal of primers at the origin of replication.

Complete mitochondrial genome of Gekko chinensis (Squamata, Gekkonidae)

We sequenced the complete mitochondrial genome of Gekko chinensis, which is an endemic species to China. The complete mitogenome is 17,906 bp in size, containing 37 genes coding for 13 proteins, two ribosomal RNAs, 22 transfer RNAs, and a control region. The A + T content of the overall base composition of H-strand is 61.1% (T: 27.6%, C: 25.5%, A: 33.5%, and G: 13.4%). The major non-coding region (control region) is 2530 bp in length and the A + T content is 67.9%. Besides, four tandem repeats were found within the control region. In Bayesian inference (BI), maximum likelihood (ML) and maximum parsimony (MP) trees, we found G. chinensis is a sister clade to Gekko swinhonis.

Complete mitochondrial genome of Pterophyllum scalare (Perciformes, Cichlidae)

The complete mitochondrial genome of Pterophyllum scalare was determined in order to characterize and compare their mitochondrial genomes (GenBank accession number KP231206). The total length of the mitochondrial genome was 16,581 bp which contained 37 genes (13 protein-coding genes, two ribosomal RNA, and 22 transfer RNAs) and a major non-coding control region which was similar to those reported mitochondrial genomes. Phylogenetic analyses identified P. scalare shared 80–86% sequence identity with other assayed fishes. The relationship was more close to the cichlid family in the perciformes. Most genes were encoded on the H-strand, except for the ND6 and eight tRNA genes, encoding on the L-strand. The nucleotide skewness for the coding strands of P. scalare (AT-skew = 0.02, GC-skew = −0.32) was biased toward A and C. The complete mitogenome may add new information to existing mitogenome data for cichlids, providing further information that may contribute for their taxonomy, evolution, and phylogeny.

Invasion genetics of the Pacific oyster Crassostrea gigas in the British Isles inferred from microsatellite and mitochondrial markers

The Pacific oyster, Crassostrea gigas, native to northeast Asia, is one of the most important cultured shellfish species. In Europe, Pacific oysters first settled along the Atlantic coasts of France at the end of the 1960s but rapidly spread and are now widely established. Twenty-two sites in the United Kingdom (UK), Ireland, Denmark, France and Spain were sampled to assess genetic diversity and differentiation. Hatchery-propagated stocks from two hatcheries located in the UK also were included. Two main genetic clusters were identified from pairwise genetic differentiation indexes, Bayesian clustering methods or neighbour-joining analysis, based on 7 microsatellite loci: (1) a Northeast cluster (including feral samples from East England, Ireland and Denmark as well as UK hatchery stocks) and (2) a Southwest cluster (including samples from South Wales, South West England, France and Spain). The Southwest cluster had significantly higher allelic richness (A) and expected heterozygosity (H e ) (A: 45.68, H e : 0.928) than in the Northeast (A: 26.58, H e : 0.883); the two diverging by a small but significant F ST value (F ST = 0.017, 95 % CI 0.014–0.021). A 739-bp fragment of the major noncoding region of the mitochondrial genome was sequenced in 248 oysters from 12 of the studied samples in Europe and in 25 oysters from Miyagi prefecture (Japan). A total of 81 haplotypes were found. Haplotype frequency analyses identified the same two clusters observed using microsatellites. This study highlights how the number and size of introduction events, aquaculture practices, genetic bottlenecks followed by genetic drift and natural dispersal can act concurrently to shape the genetic diversity and structure of introduced populations.

Base composition of the Danio chrysotaenitus complete mitochondrial genome

In this study, 16 sets of primers were used to amplify contiguous, overlapping segments of the complete mitochondrial DNA (mtDNA) of Danio chrysotaenitus in order to characterize and compare their mitochondrial genomes. The total length of the mitochondrial genome is 16,608 bp and deposited in the GenBank with accession numbers KP407138. The organization of the mitochondrial genomes was similar to those reported from other Mountain carp fishes mitochondrial genomes containing 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNAs) and a major non-coding control region (D-loop region). Most genes were encoded on the H-strand, except for the ND6 and 8 tRNA genes, encoding on the L-strand. The nucleotide skewness for the coding strands of Danio chrysotaenitus (AT-skew = 0.10, GC-skew = −0.25) is biased toward T and G. The complete mitogenome may provide important date set for the study of genetic mechanism of Danio chrysotaenitus.

The complete mitochondrial genome of the confused flour beetle Tribolium confusum (Coleoptera: Tenebrionidae)

Flour beetles of the genus Tribolium are economically important as destructive cosmopolitan pests of stored flour, corn, peanuts, and other dried agricultural products. The confused flour beetle Tribolium confusum Jacquelin du Val (1868) is one of the most important pest species of flour beetle. Here we sequenced and characterized the complete mitochondrial genome of T. confusum, the entire sequence is 15,813 bp in size with 72.8% AT content. It consists of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA), 2 ribosomal RNA (rRNA) genes and one major non-coding AT-rich region. The mitogenome of T. confusum exhibits a gene arrangement and content identical to the most common type in insects. All PCGs are start with a typical ATN initiation codon, except for the cox1, which use AAC as its start codon instead of ATN. Ten genes use standard complete termination codon (six TAA, three TAG), whereas the cox2, cox3, nad4 and nad5 genes end with single T. Except for trnS1 (AGN), all tRNA genes display typical secondary cloverleaf structures as those of other insects. The sizes of the large and small ribosomal RNA genes are 1277 and 773 bp, respectively. The AT content of the AT-rich region is 79.5%. The 5 bp conserved motif TACTA was found in the intergenic region between trnS2 (UCN) and nad1.

The complete mitochondrial genome of the hybrid of Pelteobagrus fulvidraco (♀) × Pelteobagrus vachelli (♂)

In the present of study, we have reported the complete mitochondrial DNA sequence of the hybrid of Pelteobagrus fulvidraco (♀) × Pelteobagrus vachelli (♂) that is obtained by artificial hybridization. The total length of the mitochondrial genome is 16,527 bp, with the base compositions of 30.84% A, 25.54% T, 28.22% C, and 15.40% G. It contains two ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes, and a major non-coding control region (D-loop region). The arrangement of these genes is same as that observed in the teleosts. All protein initiation codons are ATG, except for COX1 that begins with GTG. The complete mitogenome of the hybrid of P. fulvidraco (♀) × P. vachelli (♂) provides an important data set for the exploration of mitochondrial inheritance mechanism. The termination-associated sequence and critical central conserved sequences (CSB-D, CSB-E and CSB-F) are also detected.

Inheritance of the complete mitochondrial genomes Cyprinus capio furong(♀) × Cyprinus carpio var.singguonensis(♂)

In this study, 15 sets of primers were used to amplify contiguous, overlapping segments of the complete mitochondrial DNA (mtDNA) of C. capio furong(♀) × C. carpio var.singguonensis(♂) in order to characterize and compare their mitochondrial genomes. The total length of the mitochondrial genome was 16,581 bp and deposited in the GenBank with the accession number KP210473. The organization of the mitochondrial genomes contained 37 genes (13 protein-coding genes, 2 ribosomal RNA and 22 transfer RNAs) and a major non-coding control region which was similar to those reported mitochondrial genomes. Most genes were encoded on the H-strand, except for the ND6 and 8 tRNA genes, encoding on the L-strand. The nucleotide skewness for the coding strands of C. capio furong(♀) × C. carpio var.singguonensis(♂) (AT-skew = 0.12, GC-skew = −0.27) were biased toward T and G. The complete mitogenome may provide important date for the study of genetic mechanism of C. capio furong(♀) × C. carpio var.singguonensis(♂).

Complete mitochondrial genome of the hybridized fish (Oncorhynchus mykiss ♀ × Atlantic salmon ♂)

In this study, 16 sets of primers were used to amplify contiguous, overlapping segments of the complete mitochondrial DNA (mtDNA) of the hybridized fish (Oncorhynchus mykiss ♀ × Atlantic salmon ♂) in order to characterize and compare their mitochondrial genomes. The total length of the mitochondrial genome is 16,658 bp and deposited in the GenBank with accession numbers KP218514. The organization of the mitochondrial genomes contained 37 genes (13 protein-coding genes, two ribosomal RNA, and 22 transfer RNAs) and a major non-coding control region which was similar to those reported mitochondrial genomes. Most genes were encoded on the H-strand, except for the ND6 and eight tRNA genes, encoding on the L-strand. Similarity and divergence analysis also showed that hybrid offspring were genetically closer to mother parent than father parent. These results indicate that, despite hybridization, the mitochondrial genomes of these hybrids remain maternally inherited.

Inheritance of the complete mitochondrial genomes rainbow trout (Oncorhynchus mykiss) triploid

In this study, we cloned and sequenced the complete mitochondrial DNA (mtDNA) of Oncorhynchus mykiss triploid to characterize and compare their mitochondrial genomes. The total length of the mitochondrial genome is 16,656 bp with an accession number KP085590. The organization of the mitochondrial genomes was similar to those reported from other fish mitochondrial genomes containing 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNAs) and a major non-coding control region. Except for ND6 and 8 tRNAs, all other genes are encoded on the heavy strand. The nucleotide skewness for the coding strands of O. mykiss triploid (AT-skew = −0.41, GC-skew = 0.34) is biased toward T and G. The complete mitogenome may provide important date set for the study of genetic mechanism of O. mykiss.

The complete sequence of the mitochondrial genome of Liangshan pig (Sus Scrofa)

Liangshan pig is one of the famous native breeds in Sichuan province in China. It lives in the mountainous areas (about 1500–2500 m altitude) and has a superior meat quality. Here, the complete mitochondrial genome sequence of Liangshan pig was first reported. The total length of mitochondrial genome is 16,760 bp, including 34.62% A, 25.79% T, 26.20%, C and 13.39% G, with an A + T bias of 60.41%. Mitochondrial genome contains a major non-coding control region (D-Loop region), two ribosomal RNA genes, 13 protein-coding genes (PCGs), and 22 transfer RNA genes. The D-loop region is located between the tRNA-Pro and tRNA-Phe genes with a length of 1324 bp, some tandem repeat sequences was found in the region. The mitochondrial genome of Liangshan pig provides an important role in genetic mechanism.

The complete mitochondrial DNA of Tegillarca granosa and comparative mitogenomic analyses of three Arcidae species

To better understand the characteristics and the evolutionary dynamics of mt genomes in Arcidae, the complete mitochondrial genome of Tegillarca granosa was firstly determined and compared with other two Arcidae species (Scapharca broughtonii and Scapharca kagoshimensis). The complete mitochondrial genome of T. granosa was 31,589bp in length, including 12 protein-coding genes, 2 rRNA genes and 23 tRNA genes, and a major non-coding region. Three tandem repeat fragments were identified in the major non-coding region and the tandem repeat motifs of these fragments can be folded into stem–loop structures. The mitochondrial genome of the three species has several common features such as the AT content, the arrangement of the protein-coding genes, the codon usage of the protein-coding genes and AT/GC skew. However, a high level of variability is presented in the size of the genome, the number of tRNA genes and the length of non-coding sequences in the three mitogenomes. According to the phylogenetic analyses, these mitogenome-level characters are correlated with their phylogenetic relationships. It is the absence of the duplicated tRNAs and large non-coding sequences that are responsible for the length divergence of mitogenomes between T. granosa and other two Arcidae species. The phylogenetic analyses were conducted based on 12 partitioned protein genes, which support the relationship at the family level: (((Pectinidae+Ostreidae)+Mytilidae)+Arcidae).

The complete mitochondrial genome of the Colletes gigas (Hymenoptera: Colletidae: Colletinae)

The complete mitochondrial genome of the Colletes gigas (Hymenoptera: Colletidae) is determined to be 15,885 bp in length, containing 37 typical animal mitochondrial genes: 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and a major non-coding AT-rich region. All PCGs initiate with typical ATN codons and end with the complete termination codon TAA, except for the cob gene, which harbors the stop codon of TAG. Twenty-four intergenic spacers (614 bp in total) and 7 overlapping regions (37 bp in total) are dispersed throughout the whole genome. The non-coding AT-rich region is 539 bp long and contains a tandem repeat region, which has also been reported in other insects. This is the first completely sequenced mitochondrial genome of the family Colletidae.