The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai...The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.展开更多
[Objective] The sequences of mitochondrial DNA D-loop region of Xinjiang Goose with three different colors of plumage were analyzed in order to study the genetic diversity of Xinjiang Goose, as well as the phylogeny a...[Objective] The sequences of mitochondrial DNA D-loop region of Xinjiang Goose with three different colors of plumage were analyzed in order to study the genetic diversity of Xinjiang Goose, as well as the phylogeny and evolution. [Method] Ten geese were selected randomly from the core populations of grey-, mosaic- and white-plumaged Xinjiang Goose respectively with a total number of thirty as experi- mental materials, of which the blood samples were collected from the largest vein under the wing （brachial vein） for DNA extraction. Sequences of mitochondrial DNA D-loop regions were determined using DNA sequencing technology to analyze the polymorphism. In addition, the genetic distances among different populations were estimated through the comparison with the reference sequences. [Resull] The con- tents of A, G, C and T nucleotides in the D-loop region of Xinjiang Goose were 28.85%, 17.05%, 25.38% and 28.72%, respectively. The average haplotype diversity and nucleotide diversity of Xinjiang Goose were 0.583 and 0.056. Xinjiang Goose and Greylag Goose were clustered into the same group. [Conclusion] The results showed that Xinjiang Geese with three different colors of plumage all descend from Greylag Goose （Anser anser）.展开更多
Long-PCR amplification, clone and primer-walking sequencing methods were employed in determine the complete sequence of mitochondrial genome of tokay (Gekko gecko). The genome is 16 435 bp in size, contains 13 protein...Long-PCR amplification, clone and primer-walking sequencing methods were employed in determine the complete sequence of mitochondrial genome of tokay (Gekko gecko). The genome is 16 435 bp in size, contains 13 protein-coding, 2 ribosomal and 22 transfer RNA genes. The mt genome of Gekko is similar to most of the vertebrates in gene components, order, orientation, tRNA structures, low percentage of guanine and high percentage of thymine, and skews of base GC and AT. Base A was preferred at third codon positions for protein genes is similar to amphibians and fishes rather than amnion vertebrates. The standard stop codes (TAA) present only in three protein genes, less than those of most vertebrates. Transfer RNA genes range in length from 63 to 76 nt, their planar structure present characteristic clover leaf, except for tRNA-Cys and tRNA-Ser (AGY) because of lacking the D arm.展开更多
N^(6)-methyladenine(6mA)is a prevalent DNA modification and is involved in a wide range of human diseases.Previous studies have indicated that 6mA is enriched in mitochondrial DNA(mtDNA)of mammals.By employing an evol...N^(6)-methyladenine(6mA)is a prevalent DNA modification and is involved in a wide range of human diseases.Previous studies have indicated that 6mA is enriched in mitochondrial DNA(mtDNA)of mammals.By employing an evolved adenine deaminase,we developed a deaminase-mediated sequencing(DM-seq)method that could achieve genome-wide mapping of 6mA in mammalian mtDNA at single-base resolution.In this study,we used an engineered adenine deaminase,known as TadA8e protein,to map 6mA in mtDNA of hepatocellular carcinoma(HCC)by DM-seq.Through high-throughput sequencing,we identified sixteen 6mA sites in both HCC and adjacent normal tissue mtDNA.The results revealed an increased overall 6mA level in mtDNA associated with HCC.Furthermore,an elevation in 6mA level was observed alongside a decrease in the m RNA levels of the corresponding genes,indicating that increased6mA level hindered transcription processes related to these genes.These findings demonstrate that 6mA in mtDNA is correlated with HCC and provide evidence supporting the inhibitory effect of elevated 6mA level on subsequent transcriptional activity.This research illuminates the intricate relationship between 6mA modification and transcriptional regulation in the context of HCC,offering valuable insights into the role of 6mA modification in HCC pathogenesis.展开更多
Conogethes punctiferalis（Guenée）（Lepidoptera： Crambidae） was originally considered as one species with fruit-feeding type（FFT） and pinaceae-feeding type（PFT）, but it has subsequently been divided into tw...Conogethes punctiferalis（Guenée）（Lepidoptera： Crambidae） was originally considered as one species with fruit-feeding type（FFT） and pinaceae-feeding type（PFT）, but it has subsequently been divided into two different species of Conogethes punctiferalis and Conogethes pinicolalis. The relationship between the two species was investigated by phylogenetic reconstruction using maximum-likelihood（ML） parameter estimations. The phylogenetic tree and network were constructed based upon sequence data from concatenation of three genes of mitochondrial cytochrome c oxidase subunits I, II and cytochrome b which were derived from 118 samples of C. punctiferalis and 24 samples of C. pinicolalis. The phylogenetic tree and network showed that conspecific sequences were clustering together despite intraspecific variability. Here we report the results of a combined analysis of mitochondrial DNA sequences from three genes and morphological data representing powerful evidence that C. pinicolalisand C. punctiferalis are significantly different.展开更多
Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein I...Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective.展开更多
The appearance and hair color between these two subspecies Rattus rattus Sladeni and R.r. Hainanicus are similar to each other. Their most major distinctive characteristic is the length ratio of tail to body. However,...The appearance and hair color between these two subspecies Rattus rattus Sladeni and R.r. Hainanicus are similar to each other. Their most major distinctive characteristic is the length ratio of tail to body. However, this characteristic was unstable in some measuring records. In Guangdong, R.r. Hainanicus is restrictedly distributed in the west region, and R.r. Sladeni is widely distributed in the other regions of this province. In this study, we detected the sequences of mitochondrial 12S rRNA gene fragments of 9 samples from R.r. Hainanicus and R.r. Sladeni (Longmen and Hong Kong populations). These 385 nucleotide positions of 12S rRNA gene fragment include 26 variable sites and 14 parsimony-informative sites. 3 insertion/deletion sites are observed. The phylogenetic relationships among these samples were constructed by Neighbor-joining and Maximum parsimony methods. The analysis shows that R.r. Hainanicus is more closely relative to the Longmen population of R.r. Sladeni than to the Hong Kong population of R.r. Sladeni. The sequencing analysis of 12S rRNA gene fragments is not agreement on the classification of subspecies R. r. Hainanicus inferred from the morphology and geographical distribution. The morphological variation of R.r. Hainanicus should result from the natural selection, which causes local adaptation and geographic isolation.展开更多
The 5’-end of the mitochondrial control region sequences of three flatfishes (Pleuronectiformes: Pleuronectidae) were amplified and sequenced. These sequences were compared with those of other three Pleuronectids spe...The 5’-end of the mitochondrial control region sequences of three flatfishes (Pleuronectiformes: Pleuronectidae) were amplified and sequenced. These sequences were compared with those of other three Pleuronectids species retrieved from GenBank. A phylogenetic tree was constructed based on the partial control region sequences. The results of phyloge- netic analysis are consistent with those of conventional systematics. Compared to previous studies, the structure of the 5’-end of mitochondrial control region was analyzed. The terminal associated sequence motif and its complementary motif were i- dentified at the 5’-end of the sequences. A conserved sequence block, named as CM5’d, was identified in the 5’-end of con- trol region sequences in all Pleuronectids. Another central conserved sequence block, named as CSB-F, was detected in the central conserved blocks.展开更多
The brown marmorated stink bug, <i><span style="font-family:Verdana;">Halyomorpha halys</span></i><span style="font-family:Verdana;"> (Stal) (Hemiptera: Pentatomidae) ...The brown marmorated stink bug, <i><span style="font-family:Verdana;">Halyomorpha halys</span></i><span style="font-family:Verdana;"> (Stal) (Hemiptera: Pentatomidae) is an invasive species native to East Asia that has spread across Asia, Europe</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and North America. </span><i><span style="font-family:Verdana;">H. halys </span></i><span style="font-family:Verdana;">causes damages to various grains, fruits, and vegetables, which is exemplified by the significant damage to the hazelnut harvest in Georgia (during 2016). This report describes the first attempted genetic study of the spread of </span><i><span style="font-family:Verdana;">H. halys</span></i><span style="font-family:Verdana;"> in Georgia. The first main goal of this research was to identify the haplotype of an invasive population in Georgia. For this purpose, the mitochondrial cytochrome c oxidase I subunit (</span><i><span style="font-family:Verdana;">COI</span></i><span style="font-family:Verdana;">) gene fragment from 65 samples</span><i><span style="font-family:Verdana;"> of H. halys</span></i><span style="font-family:Verdana;"> collected from different regions across Georgia was sequenced on an Applied Biosystems 3100 or 3700 genetic analyzer. In all cases, only the H1 haplotype, which is native to China, was identified. The second goal of this research was to determine the complete mitochondrial DNA sequence of </span><i><span style="font-family:Verdana;">H. halys</span></i><span style="font-family:Verdana;"> (Stal) specimens collected </span><span style="font-family:Verdana;">across Georgia. The complete mitochondrial DNA of H1 haplotype s</span><span style="font-family:Verdana;">equenced on an Illumina MiSeq platform. The mitochondrial DNA of the Georgian H1 haplotype has a length of 15</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;">478 base pairs. Using the sequence of the H22 haplotype of </span><i><span style="font-family:Verdana;">H. halys </span></i><span style="font-family:Verdana;">(native to Korea) as a reference, 62 single nucleotide polymorphisms (SNPs), three inversions</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and four single T insertions were identified. Furthermore, 60 SNPs and four insertions in two tRNA and one rRNA genes were identified among 18 mitochondrial genes from the Georgian H1 haplotype. Nine of these SNPs resulted in amino acid substitutions. Furthermore, the detection of SNPs revealed many other polymorphic sites beyond the </span><i><span style="font-family:Verdana;">COI</span></i><span style="font-family:Verdana;"> gene, which can be used to detect new haplotypes.</span></span>展开更多
Eucalyptus urophylla×E.grandis is a major hybrid species of timber plantations.However,our under-standing of Eucalyptus mitochondrial genome,especially within the Myrtaceae family,is limited.In this study,we empl...Eucalyptus urophylla×E.grandis is a major hybrid species of timber plantations.However,our under-standing of Eucalyptus mitochondrial genome,especially within the Myrtaceae family,is limited.In this study,we employed hybrid sequencing combining the Illumina and Oxford Nanopore sequencing to assemble and annotate the mitogenome(mtDNA)of E.urophylla×E.grandis.Our results reveal a structure characterized by one circular mol-ecule,with a cumulative length of 483,907 base pairs(bp)and a GC content of 44.96%.The circular molecule collec-tively harbored 59 annotated genes.Among these,38 were unique protein-coding genes(PCGs),accompanied by 18 transfer RNA(tRNA)genes and 3 ribosomal RNA(rRNA)genes.Our study also examined repetitive sequences,RNA editing sites,and intracellular sequence transfers within the mtDNA.Furthermore,we conducted a phylogenetic analy-sis between E.urophylla×E.grandis and 30 closely related species based on genetic affinities.The outcomes furnish a high-quality organelle genome for E.urophylla×E.grandis,thereby explaining basic insights into organelle genome evo-lution and phylogenetic relationships.展开更多
Objective: To investigate the mutati ons in the D-loop region of mitochondrial DNA (mtDNA) in gastric cancer. Methods: The mtDNA of D-loop region was amplified by PCR and sequence d in 20 samples from gastric cancer ...Objective: To investigate the mutati ons in the D-loop region of mitochondrial DNA (mtDNA) in gastric cancer. Methods: The mtDNA of D-loop region was amplified by PCR and sequence d in 20 samples from gastric cancer tissue and adjacent normal membrane. Results: There were 7/20(35%) mutations in the mtDNA of D-loop regio n in gastric cancer patients. There were four microsatellite instabilities among the 18 mutations. Nine new polymorphisms were identified in 20 patients. Conclusion: The mtDNA of D-loop region might be highly polymorphoric and the mutation rate is high in patients with gastric cancer.展开更多
The purpose of this study was to investigate mitochondrial DNA (mtDNA) hypervariable segment-I (HVS-I) C-stretch variations and explore the significance of these variations in forensic and population genetics studies....The purpose of this study was to investigate mitochondrial DNA (mtDNA) hypervariable segment-I (HVS-I) C-stretch variations and explore the significance of these variations in forensic and population genetics studies. The C-stretch sequence variation was studied in 919 unrelated individuals from 8 Chinese ethnic groups using both direct and clone sequencing ap-proaches. Thirty eight C-stretch haplotypes were identified, and some novel and population specific haplotypes were also detected. The C-stretch genetic diversity (GD) values were relatively high, and probability (P) values were low. Additionally, C-stretch length heteroplasmy was observed in approximately 9% of individuals studied. There was a significant correlation (r=-0.961, P<0.01) between the expansion of the cytosine sequence length in the C-stretch of HVS-I and a reduction in the number of up-stream adenines. These results indicate that the C-stretch could be a useful genetic maker in forensic identification of Chinese populations. The results from the Fst and dA genetic distance matrix, neighbor-joining tree, and principal component map also suggest that C-stretch could be used as a reliable genetic marker in population genetics.展开更多
Mitochondrial DNA sequences transferred to the nucleus give rise to the so-called nuclear mitochondrial DNA （numt）. In the GenBank database, 244 numts have been found in six orders of birds （Anseriformes, Columbifo...Mitochondrial DNA sequences transferred to the nucleus give rise to the so-called nuclear mitochondrial DNA （numt）. In the GenBank database, 244 numts have been found in six orders of birds （Anseriformes, Columbiformes, Falconiformes, Charadriiformes, Galliformes and Passeriformes）. Sequences alignment （NCBI-BLASTN） was carded out with mitochondrial and corresponding nuclear genome sequences in nine vertebrate species. The sequences with high homology were considered as numts. The number of numts ranged from 15 in chicken to 159 in chimpanzee. The sequences of numts in macaque, chimpanzee, and human spanned 100% of the entire mammalian mitochondrial genome. The reconstructed frequency of the mitochondrial gene transferred to the nucleus demonstrated that the rRNA genes had high frequencies than other mitochondrial genes. Using the RepeatMasker program, the transposable elements were detected in the flanking regions of each numt. The results showed that less than 5% of the flanking sequences were made up of repetitive elements in chicken. The GC content of 5＇- and 3＇-flanking regions of numts in nine species was less than 44%. The analysis of the flanking sequences provided a valuable understanding for future study on mechanism of mitochondrial gene transfer to the nucleus and the site of numt integration.展开更多
RNA editing changes the nucleotides at the transcript level of mitochondrial genes which results in synthesis of functional proteins.This study was designed to find the editing sites which could be implicated in male ...RNA editing changes the nucleotides at the transcript level of mitochondrial genes which results in synthesis of functional proteins.This study was designed to find the editing sites which could be implicated in male fertility restoration and to develop editing based markers for differentiation of cytoplasmic male sterility and maintainer lines from each other.DNA and RNA from young panicles were isolated from three-line system of hybrid rice PRH10,wild abortive(WA)cytoplasm based male sterile(A line Pusa 6A),maintainer(B line Pusa 6B)and restorer(R line PRR78)lines.Pusa 6A and PRR78 having the same WA cytoplasm are allo-nuclear and iso-cytpolasmic lines.The genomic and cDNA amplicons for eight mitochondrial genes(18SrRNA,atp6,atp9,cobII,coxI,coxIII,nadI and rps3)were sequenced and compared.Differences in genomic and cDNA sequences were considered as editing.Two hundred and thirty editing sites having base substitution or insertion/deletion were identified with the highest in 18SrRNA(5.74%)and the lowest in coxI(0.60%).The highest editing sites were observed in fertile maintainer Pusa 6B followed by PRR78 and Pusa 6A,of which random five editing sites in five different rice mitochondrial transcripts namely atp9,cobII,coxIII,rps3 and 18SrRNA were chosen and validated through cleaved amplified polymorphism sequence(CAPS)analysis and found to be partially edited in four genes.The identical editing sites of different mitochondrial genes from maintainer and restorer lines might reflect their possible contribution to fertility restoration of sterile WA cytoplasm.展开更多
[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region（CR） were...[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region（CR） were PCR amplified from the wild R. curvicornis populations from the Liaodong Bay（n=22） and the northern Yellow Sea（n=18）, sequenced and analyzed for genetic diversity. [Result] The contents of A, T, C and G of 624 bp COⅠ gene were 24.09%, 31.04%, 25.28%, and 19.59%, and those of 460 bp CR fragment were 32.96%, 32.80%, 14.86% and 19.38%, respectively. The total number of variable sites, average number of nucleotide differences（ k）, haplotype diversity（H） and nucleotide diversity（π） based on COⅠ gene were 38, 4.67,（0.96±0.02） and（0.007 5±0.004 2）, and those based on CR fragment were 26, 3.35,（0.97 ±0.02） and（0.007 3±0.004 3）, respectively. Based on mitochondrial COⅠ gene and CR, the genetic diversity of Liaodong Bay population was lower than that of the northern Yellow Sea population. The AMOVA analysis based on CR fragments revealed almost significant genetic divergence between the Liaodong Bay and the northern Yellow Sea populations, while there was no significant genetic divergence based on COⅠ gene. The results showed that CR and COⅠ gene are effective molecular markers for detecting the genetic diversity of R. curvicornis population, while CR is more reliable than COⅠ gene in detecting the genetic structure. [Conclusion] CR is an appropriate marker for genetic analysis of marine fish population.展开更多
A new method is presented with which we isolated milochondrial DNA from fresh carp liver usingdifferential centrifugation and DNase treatment that gave high yield of purified product with an easyand economical procedu...A new method is presented with which we isolated milochondrial DNA from fresh carp liver usingdifferential centrifugation and DNase treatment that gave high yield of purified product with an easyand economical procedure. Highly distinct bands were displayed in agarose gel electrophoresls ofthe product digested with restrictlon enzymes, which were successfully used in constructingrestriction map and molecular clone of mitochondrial genes. With DNAs thus obtained, we havecloned cysteine tRNA gene (tRNA^(Cys) gene) of carp mitochondria, determined the nucleotide sequenceof it and the light strand origin, and depicted the cloverleaf secondary structure of tDNA^(Cya) and thelight strand origin. Analysis of nucleotide sequences of tRNA^(Cy) genes of 5 vertebrates has revealedunusual features of carp mitochondrial tRNA^(Cy) gene as compared with their cytoplasmic counter-parts, Altogether 36 bases were found in the light strand origin of carp mitochondriaf: 11 pairs in thestem; and 14 bases in the loop. As compared with those of other 11 vertebrate species, the sequenceof the stem is very conservative while both sequence and length of the loop are quite variable. Thestructure of the stem-loop may play an important role in light strand replication.展开更多
基金Supported by the National Natural Science Foundation of China(No.32172979)the Natural Science Foundation of Fujian Province(No.2021J05159)the 2023 Special Program for Promoting High-Quality Development of Marine and Fishery Industry in Fujian Province(No.PJHYF-L-2023-2)。
文摘The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.
基金Supported by the Fond for Open Projects of Xinjiang Key Laboratory of Herbivore Nutrition for Meat&Milk Production~~
文摘[Objective] The sequences of mitochondrial DNA D-loop region of Xinjiang Goose with three different colors of plumage were analyzed in order to study the genetic diversity of Xinjiang Goose, as well as the phylogeny and evolution. [Method] Ten geese were selected randomly from the core populations of grey-, mosaic- and white-plumaged Xinjiang Goose respectively with a total number of thirty as experi- mental materials, of which the blood samples were collected from the largest vein under the wing （brachial vein） for DNA extraction. Sequences of mitochondrial DNA D-loop regions were determined using DNA sequencing technology to analyze the polymorphism. In addition, the genetic distances among different populations were estimated through the comparison with the reference sequences. [Resull] The con- tents of A, G, C and T nucleotides in the D-loop region of Xinjiang Goose were 28.85%, 17.05%, 25.38% and 28.72%, respectively. The average haplotype diversity and nucleotide diversity of Xinjiang Goose were 0.583 and 0.056. Xinjiang Goose and Greylag Goose were clustered into the same group. [Conclusion] The results showed that Xinjiang Geese with three different colors of plumage all descend from Greylag Goose （Anser anser）.
文摘Long-PCR amplification, clone and primer-walking sequencing methods were employed in determine the complete sequence of mitochondrial genome of tokay (Gekko gecko). The genome is 16 435 bp in size, contains 13 protein-coding, 2 ribosomal and 22 transfer RNA genes. The mt genome of Gekko is similar to most of the vertebrates in gene components, order, orientation, tRNA structures, low percentage of guanine and high percentage of thymine, and skews of base GC and AT. Base A was preferred at third codon positions for protein genes is similar to amphibians and fishes rather than amnion vertebrates. The standard stop codes (TAA) present only in three protein genes, less than those of most vertebrates. Transfer RNA genes range in length from 63 to 76 nt, their planar structure present characteristic clover leaf, except for tRNA-Cys and tRNA-Ser (AGY) because of lacking the D arm.
基金supported by the National Natural Science Foundation of China(No.22277093)the Key Research and Development Project of Hubei Province(No.2023BCB094)。
文摘N^(6)-methyladenine(6mA)is a prevalent DNA modification and is involved in a wide range of human diseases.Previous studies have indicated that 6mA is enriched in mitochondrial DNA(mtDNA)of mammals.By employing an evolved adenine deaminase,we developed a deaminase-mediated sequencing(DM-seq)method that could achieve genome-wide mapping of 6mA in mammalian mtDNA at single-base resolution.In this study,we used an engineered adenine deaminase,known as TadA8e protein,to map 6mA in mtDNA of hepatocellular carcinoma(HCC)by DM-seq.Through high-throughput sequencing,we identified sixteen 6mA sites in both HCC and adjacent normal tissue mtDNA.The results revealed an increased overall 6mA level in mtDNA associated with HCC.Furthermore,an elevation in 6mA level was observed alongside a decrease in the m RNA levels of the corresponding genes,indicating that increased6mA level hindered transcription processes related to these genes.These findings demonstrate that 6mA in mtDNA is correlated with HCC and provide evidence supporting the inhibitory effect of elevated 6mA level on subsequent transcriptional activity.This research illuminates the intricate relationship between 6mA modification and transcriptional regulation in the context of HCC,offering valuable insights into the role of 6mA modification in HCC pathogenesis.
基金supported by China Agriculture Research System(CARS-02)Beijing Municipal Sci-Tech Program(Z111100056811009)
文摘Conogethes punctiferalis（Guenée）（Lepidoptera： Crambidae） was originally considered as one species with fruit-feeding type（FFT） and pinaceae-feeding type（PFT）, but it has subsequently been divided into two different species of Conogethes punctiferalis and Conogethes pinicolalis. The relationship between the two species was investigated by phylogenetic reconstruction using maximum-likelihood（ML） parameter estimations. The phylogenetic tree and network were constructed based upon sequence data from concatenation of three genes of mitochondrial cytochrome c oxidase subunits I, II and cytochrome b which were derived from 118 samples of C. punctiferalis and 24 samples of C. pinicolalis. The phylogenetic tree and network showed that conspecific sequences were clustering together despite intraspecific variability. Here we report the results of a combined analysis of mitochondrial DNA sequences from three genes and morphological data representing powerful evidence that C. pinicolalisand C. punctiferalis are significantly different.
基金supported by the National Natural Science Foundation of China(31640001 and T2350005 to C.X.,U21A20148 to X.Z.and C.X.)Ministry of Science and Technology of China(2021ZD0140300 to C.X.)+2 种基金Natural Science Foundation of Hainan Province(No.822RC703 for J.L.)Foundation of Hainan Educational Committee(No.Hnky2022-27 for J.L.)Presidential Foundation of Hefei Institutes of Physical Science,Chinese Academy of Sciences(Y96XC11131,E26CCG27,and E26CCD15 to C.X.,E36CWGBR24B and E36CZG14132 to T.C.)。
文摘Iron-sulfur clusters(ISC)are essential cofactors for proteins involved in various biological processes,such as electron transport,biosynthetic reactions,DNA repair,and gene expression regulation.ISC assembly protein IscA1(or MagR)is found within the mitochondria of most eukaryotes.Magnetoreceptor(MagR)is a highly conserved A-type iron and iron-sulfur cluster-binding protein,characterized by two distinct types of iron-sulfur clusters,[2Fe-2S]and[3Fe-4S],each conferring unique magnetic properties.MagR forms a rod-like polymer structure in complex with photoreceptive cryptochrome(Cry)and serves as a putative magnetoreceptor for retrieving geomagnetic information in animal navigation.Although the N-terminal sequences of MagR vary among species,their specific function remains unknown.In the present study,we found that the N-terminal sequences of pigeon MagR,previously thought to serve as a mitochondrial targeting signal(MTS),were not cleaved following mitochondrial entry but instead modulated the efficiency with which iron-sulfur clusters and irons are bound.Moreover,the N-terminal region of MagR was required for the formation of a stable MagR/Cry complex.Thus,the N-terminal sequences in pigeon MagR fulfil more important functional roles than just mitochondrial targeting.These results further extend our understanding of the function of MagR and provide new insights into the origin of magnetoreception from an evolutionary perspective.
文摘The appearance and hair color between these two subspecies Rattus rattus Sladeni and R.r. Hainanicus are similar to each other. Their most major distinctive characteristic is the length ratio of tail to body. However, this characteristic was unstable in some measuring records. In Guangdong, R.r. Hainanicus is restrictedly distributed in the west region, and R.r. Sladeni is widely distributed in the other regions of this province. In this study, we detected the sequences of mitochondrial 12S rRNA gene fragments of 9 samples from R.r. Hainanicus and R.r. Sladeni (Longmen and Hong Kong populations). These 385 nucleotide positions of 12S rRNA gene fragment include 26 variable sites and 14 parsimony-informative sites. 3 insertion/deletion sites are observed. The phylogenetic relationships among these samples were constructed by Neighbor-joining and Maximum parsimony methods. The analysis shows that R.r. Hainanicus is more closely relative to the Longmen population of R.r. Sladeni than to the Hong Kong population of R.r. Sladeni. The sequencing analysis of 12S rRNA gene fragments is not agreement on the classification of subspecies R. r. Hainanicus inferred from the morphology and geographical distribution. The morphological variation of R.r. Hainanicus should result from the natural selection, which causes local adaptation and geographic isolation.
基金the Shandong Foundation of Sciences(No.Y2000D04) the National Key Basic Research Program from the Ministry of Science and Technology of China(No.G19990437).
文摘The 5’-end of the mitochondrial control region sequences of three flatfishes (Pleuronectiformes: Pleuronectidae) were amplified and sequenced. These sequences were compared with those of other three Pleuronectids species retrieved from GenBank. A phylogenetic tree was constructed based on the partial control region sequences. The results of phyloge- netic analysis are consistent with those of conventional systematics. Compared to previous studies, the structure of the 5’-end of mitochondrial control region was analyzed. The terminal associated sequence motif and its complementary motif were i- dentified at the 5’-end of the sequences. A conserved sequence block, named as CM5’d, was identified in the 5’-end of con- trol region sequences in all Pleuronectids. Another central conserved sequence block, named as CSB-F, was detected in the central conserved blocks.
文摘The brown marmorated stink bug, <i><span style="font-family:Verdana;">Halyomorpha halys</span></i><span style="font-family:Verdana;"> (Stal) (Hemiptera: Pentatomidae) is an invasive species native to East Asia that has spread across Asia, Europe</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and North America. </span><i><span style="font-family:Verdana;">H. halys </span></i><span style="font-family:Verdana;">causes damages to various grains, fruits, and vegetables, which is exemplified by the significant damage to the hazelnut harvest in Georgia (during 2016). This report describes the first attempted genetic study of the spread of </span><i><span style="font-family:Verdana;">H. halys</span></i><span style="font-family:Verdana;"> in Georgia. The first main goal of this research was to identify the haplotype of an invasive population in Georgia. For this purpose, the mitochondrial cytochrome c oxidase I subunit (</span><i><span style="font-family:Verdana;">COI</span></i><span style="font-family:Verdana;">) gene fragment from 65 samples</span><i><span style="font-family:Verdana;"> of H. halys</span></i><span style="font-family:Verdana;"> collected from different regions across Georgia was sequenced on an Applied Biosystems 3100 or 3700 genetic analyzer. In all cases, only the H1 haplotype, which is native to China, was identified. The second goal of this research was to determine the complete mitochondrial DNA sequence of </span><i><span style="font-family:Verdana;">H. halys</span></i><span style="font-family:Verdana;"> (Stal) specimens collected </span><span style="font-family:Verdana;">across Georgia. The complete mitochondrial DNA of H1 haplotype s</span><span style="font-family:Verdana;">equenced on an Illumina MiSeq platform. The mitochondrial DNA of the Georgian H1 haplotype has a length of 15</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;">478 base pairs. Using the sequence of the H22 haplotype of </span><i><span style="font-family:Verdana;">H. halys </span></i><span style="font-family:Verdana;">(native to Korea) as a reference, 62 single nucleotide polymorphisms (SNPs), three inversions</span></span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and four single T insertions were identified. Furthermore, 60 SNPs and four insertions in two tRNA and one rRNA genes were identified among 18 mitochondrial genes from the Georgian H1 haplotype. Nine of these SNPs resulted in amino acid substitutions. Furthermore, the detection of SNPs revealed many other polymorphic sites beyond the </span><i><span style="font-family:Verdana;">COI</span></i><span style="font-family:Verdana;"> gene, which can be used to detect new haplotypes.</span></span>
基金supported by the Fundamental Research Funds for the Central Universities(2021ZY62)the National Natural ScienceFoundation of China(31901337)the 5·5 Engineering Research&Innovation Team Project of Beijing Forestry University(BLRC2023C06).
文摘Eucalyptus urophylla×E.grandis is a major hybrid species of timber plantations.However,our under-standing of Eucalyptus mitochondrial genome,especially within the Myrtaceae family,is limited.In this study,we employed hybrid sequencing combining the Illumina and Oxford Nanopore sequencing to assemble and annotate the mitogenome(mtDNA)of E.urophylla×E.grandis.Our results reveal a structure characterized by one circular mol-ecule,with a cumulative length of 483,907 base pairs(bp)and a GC content of 44.96%.The circular molecule collec-tively harbored 59 annotated genes.Among these,38 were unique protein-coding genes(PCGs),accompanied by 18 transfer RNA(tRNA)genes and 3 ribosomal RNA(rRNA)genes.Our study also examined repetitive sequences,RNA editing sites,and intracellular sequence transfers within the mtDNA.Furthermore,we conducted a phylogenetic analy-sis between E.urophylla×E.grandis and 30 closely related species based on genetic affinities.The outcomes furnish a high-quality organelle genome for E.urophylla×E.grandis,thereby explaining basic insights into organelle genome evo-lution and phylogenetic relationships.
文摘Objective: To investigate the mutati ons in the D-loop region of mitochondrial DNA (mtDNA) in gastric cancer. Methods: The mtDNA of D-loop region was amplified by PCR and sequence d in 20 samples from gastric cancer tissue and adjacent normal membrane. Results: There were 7/20(35%) mutations in the mtDNA of D-loop regio n in gastric cancer patients. There were four microsatellite instabilities among the 18 mutations. Nine new polymorphisms were identified in 20 patients. Conclusion: The mtDNA of D-loop region might be highly polymorphoric and the mutation rate is high in patients with gastric cancer.
基金supported by the Sciences and Technological Fundamental Resources Data of the Ministry of Education, China (No. 505015)the Key Project for Science and Technology of Shaanxi Province, China (No. 2004K09-G12)
文摘The purpose of this study was to investigate mitochondrial DNA (mtDNA) hypervariable segment-I (HVS-I) C-stretch variations and explore the significance of these variations in forensic and population genetics studies. The C-stretch sequence variation was studied in 919 unrelated individuals from 8 Chinese ethnic groups using both direct and clone sequencing ap-proaches. Thirty eight C-stretch haplotypes were identified, and some novel and population specific haplotypes were also detected. The C-stretch genetic diversity (GD) values were relatively high, and probability (P) values were low. Additionally, C-stretch length heteroplasmy was observed in approximately 9% of individuals studied. There was a significant correlation (r=-0.961, P<0.01) between the expansion of the cytosine sequence length in the C-stretch of HVS-I and a reduction in the number of up-stream adenines. These results indicate that the C-stretch could be a useful genetic maker in forensic identification of Chinese populations. The results from the Fst and dA genetic distance matrix, neighbor-joining tree, and principal component map also suggest that C-stretch could be used as a reliable genetic marker in population genetics.
基金the National Natural Science Foundation of China (No. 30470936)
文摘Mitochondrial DNA sequences transferred to the nucleus give rise to the so-called nuclear mitochondrial DNA （numt）. In the GenBank database, 244 numts have been found in six orders of birds （Anseriformes, Columbiformes, Falconiformes, Charadriiformes, Galliformes and Passeriformes）. Sequences alignment （NCBI-BLASTN） was carded out with mitochondrial and corresponding nuclear genome sequences in nine vertebrate species. The sequences with high homology were considered as numts. The number of numts ranged from 15 in chicken to 159 in chimpanzee. The sequences of numts in macaque, chimpanzee, and human spanned 100% of the entire mammalian mitochondrial genome. The reconstructed frequency of the mitochondrial gene transferred to the nucleus demonstrated that the rRNA genes had high frequencies than other mitochondrial genes. Using the RepeatMasker program, the transposable elements were detected in the flanking regions of each numt. The results showed that less than 5% of the flanking sequences were made up of repetitive elements in chicken. The GC content of 5＇- and 3＇-flanking regions of numts in nine species was less than 44%. The analysis of the flanking sequences provided a valuable understanding for future study on mechanism of mitochondrial gene transfer to the nucleus and the site of numt integration.
文摘RNA editing changes the nucleotides at the transcript level of mitochondrial genes which results in synthesis of functional proteins.This study was designed to find the editing sites which could be implicated in male fertility restoration and to develop editing based markers for differentiation of cytoplasmic male sterility and maintainer lines from each other.DNA and RNA from young panicles were isolated from three-line system of hybrid rice PRH10,wild abortive(WA)cytoplasm based male sterile(A line Pusa 6A),maintainer(B line Pusa 6B)and restorer(R line PRR78)lines.Pusa 6A and PRR78 having the same WA cytoplasm are allo-nuclear and iso-cytpolasmic lines.The genomic and cDNA amplicons for eight mitochondrial genes(18SrRNA,atp6,atp9,cobII,coxI,coxIII,nadI and rps3)were sequenced and compared.Differences in genomic and cDNA sequences were considered as editing.Two hundred and thirty editing sites having base substitution or insertion/deletion were identified with the highest in 18SrRNA(5.74%)and the lowest in coxI(0.60%).The highest editing sites were observed in fertile maintainer Pusa 6B followed by PRR78 and Pusa 6A,of which random five editing sites in five different rice mitochondrial transcripts namely atp9,cobII,coxIII,rps3 and 18SrRNA were chosen and validated through cleaved amplified polymorphism sequence(CAPS)analysis and found to be partially edited in four genes.The identical editing sites of different mitochondrial genes from maintainer and restorer lines might reflect their possible contribution to fertility restoration of sterile WA cytoplasm.
基金Supported by the National Key R&D Program of China(2017YFC1404400)The National Natural Science Foundation of China(31770458)
文摘[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region（CR） were PCR amplified from the wild R. curvicornis populations from the Liaodong Bay（n=22） and the northern Yellow Sea（n=18）, sequenced and analyzed for genetic diversity. [Result] The contents of A, T, C and G of 624 bp COⅠ gene were 24.09%, 31.04%, 25.28%, and 19.59%, and those of 460 bp CR fragment were 32.96%, 32.80%, 14.86% and 19.38%, respectively. The total number of variable sites, average number of nucleotide differences（ k）, haplotype diversity（H） and nucleotide diversity（π） based on COⅠ gene were 38, 4.67,（0.96±0.02） and（0.007 5±0.004 2）, and those based on CR fragment were 26, 3.35,（0.97 ±0.02） and（0.007 3±0.004 3）, respectively. Based on mitochondrial COⅠ gene and CR, the genetic diversity of Liaodong Bay population was lower than that of the northern Yellow Sea population. The AMOVA analysis based on CR fragments revealed almost significant genetic divergence between the Liaodong Bay and the northern Yellow Sea populations, while there was no significant genetic divergence based on COⅠ gene. The results showed that CR and COⅠ gene are effective molecular markers for detecting the genetic diversity of R. curvicornis population, while CR is more reliable than COⅠ gene in detecting the genetic structure. [Conclusion] CR is an appropriate marker for genetic analysis of marine fish population.
基金This work was supported by grant from National Foundation of Natural Sciences of China.
文摘A new method is presented with which we isolated milochondrial DNA from fresh carp liver usingdifferential centrifugation and DNase treatment that gave high yield of purified product with an easyand economical procedure. Highly distinct bands were displayed in agarose gel electrophoresls ofthe product digested with restrictlon enzymes, which were successfully used in constructingrestriction map and molecular clone of mitochondrial genes. With DNAs thus obtained, we havecloned cysteine tRNA gene (tRNA^(Cys) gene) of carp mitochondria, determined the nucleotide sequenceof it and the light strand origin, and depicted the cloverleaf secondary structure of tDNA^(Cya) and thelight strand origin. Analysis of nucleotide sequences of tRNA^(Cy) genes of 5 vertebrates has revealedunusual features of carp mitochondrial tRNA^(Cy) gene as compared with their cytoplasmic counter-parts, Altogether 36 bases were found in the light strand origin of carp mitochondriaf: 11 pairs in thestem; and 14 bases in the loop. As compared with those of other 11 vertebrate species, the sequenceof the stem is very conservative while both sequence and length of the loop are quite variable. Thestructure of the stem-loop may play an important role in light strand replication.
