[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
In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release f...In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.展开更多
BACKGROUND:Pulmonary fibrosis(PF)is one of the main causes of death in patients with paraquat(PQ)poisoning.This study aimed to evaluate the relationship between mitochondrial fi ssion and oxidative stress in PQ-induce...BACKGROUND:Pulmonary fibrosis(PF)is one of the main causes of death in patients with paraquat(PQ)poisoning.This study aimed to evaluate the relationship between mitochondrial fi ssion and oxidative stress in PQ-induced epithelial-mesenchymal transition(EMT)and PF.METHODS:C57BL/6 mice and MLE-12 cells were exposed to PQ to construct a PF model in vivo and in vitro.Histological changes in the lungs were examined by hematoxylin and eosin(H&E)staining.Mitochondrial morphology was detected by MitoTracker®Deep Red FM or transmission electron microscopy(TEM).Western blotting and immunofluorescence were used to determine the expression of protein.The migration ability of the cells was detected by the cell scratch test.Mitochondrial DNA(mtDNA)levels were assessed by real-time polymerase chain reaction(PCR).Enzyme-linked immunosorbent assay(ELISA)was applied to detect cytokine levels.Superoxide dismutase(SOD)activity and the levels of glutathione(GSH)and malondialdehyde(MDA)were detected by chemichromatometry.RESULTS:PQ exposure caused EMT and PF in vivo and in vitro.PQ destroyed mitochondrial structure and enhanced the expression of dynamin-related protein 1(Drp1),which were accompanied by oxidative stress.Inhibiting mitochondrial fission using mitochondrial division inhibitor-1(Mdivi-1),a selective inhibitor of Drp1,attenuated PQ-induced EMT and oxidative damage.Treatment with N-acetyl-L-cysteine(NAC),an antioxidant,reduced Drp1 expression,attenuated mitochondrial structure damage and inhibited PQ-induced EMT and PF.Both Mdivi-1 and NAC treatment markedly suppressed mtDNA release,the expression of Toll-like receptor 9(TLR9)and phosphorylation(P)-NF-κB p65 as well as cytokines(interleukin 6[IL-6],interleukin-1β[IL-1β],and tumor necrosis factor-α[TNF-α])production.CONCLUSION:Mutual promotion of mitochondrial fission and oxidative stress contributes to EMT in PQ-induced PF,which is associated with the mtDNA/TLR9/NF-κB pathway.展开更多
BACKGROUND Globally,the World Health Organization ranks major depressive disorder(MDD)as the leading cause of disability.However,MDD molecular etiology is still poorly understood.AIM To explore the possible associatio...BACKGROUND Globally,the World Health Organization ranks major depressive disorder(MDD)as the leading cause of disability.However,MDD molecular etiology is still poorly understood.AIM To explore the possible association between mitochondrial ND6 T14502C mutation and MDD.METHODS Clinical data were collected from two pedigrees,and detailed mitochondrial genomes were obtained for the two proband members.The assessment of the resulting variants included an evaluation of their evolutionary conservation,allelic frequencies,as well as their structural and functional consequences.Detailed mitochondrial whole genome analysis,phylogenetic,and haplotype analysis were performed on the probands.RESULTS Herein,we reported the clinical,genetic,and molecular profiling of two Chinese families afflicted with MDD.These Chinese families exhibited not only a range of onset and severity ages in their depression but also extremely low penetrances to MDD.Sequence analyses of mitochondrial genomes from these pedigrees have resulted in the identification of a homoplasmic T14502C(I58V)mutation.The polymorphism is located at a highly conserved isoleucine at position 58 of ND6 and distinct mitochondrial DNA(mtDNA)polymorphisms originating from haplogroups M10 and H2.CONCLUSION Identifying the T14502C mutation in two individuals with no genetic relation who exhibit symptoms of depression provides compelling evidence that this mutation may be implicated in MDD development.Nonetheless,the two Chinese pedigrees that carried the T14502C mutation did not exhibit any functionally significant mutations in their mtDNA.Therefore,the phenotypic expression of the T14502C mutation related to MDD may be influenced by the nuclear modifier gene(s)or environmental factors.展开更多
Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overf...Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.展开更多
BACKGROUND Here,we present a unique case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes(MELAS)syndrome,which initially appeared to be autoimmune encephalitis and was ultimately confir...BACKGROUND Here,we present a unique case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes(MELAS)syndrome,which initially appeared to be autoimmune encephalitis and was ultimately confirmed as MELAS with the mitochondrial DNA 3243A>G mutation.CASE SUMMARY A 58-year-old female presented with acute-onset speech impediment and auditory hallucinations,symmetrical bitemporal lobe abnormalities,clinical and laboratory findings,and a lack of relevant prodromal history,which suggested diagnosis of autoimmune encephalitis.Further work-up,in conjunction with the patient’s medical history,family history,and lactate peak on brain lesions on magnetic resonance imaging,suggested a mitochondrial disorder.Mitochondrial genome analysis revealed the m.3243A>G variant in the MT-TL1 gene,which led to a diagnosis of MELAS syndrome.CONCLUSION This case underscores the importance of considering MELAS as a potential cause of autoimmune encephalitis even if patients are over 40 years of age,as the symptoms and signs are atypical for MELAS syndrome.展开更多
Objective The study aimed to estimate the benchmark dose(BMD)of coke oven emissions(COEs)exposure based on mitochondrial damage with the mitochondrial DNA copy number(mtDNAcn)as a biomarker.Methods A total of 782 subj...Objective The study aimed to estimate the benchmark dose(BMD)of coke oven emissions(COEs)exposure based on mitochondrial damage with the mitochondrial DNA copy number(mtDNAcn)as a biomarker.Methods A total of 782 subjects were recruited,including 238 controls and 544 exposed workers.The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction.Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95%confidence lower limit(BMDL).Results The mtDNAcn of the exposure group was lower than that of the control group(0.60±0.29 vs.1.03±0.31;P<0.001).A dose-response relationship was shown between the mtDNAcn damage and COEs.Using the Benchmark Dose Software,the occupational exposure limits(OELs)for COEs exposure in males was 0.00190 mg/m^(3).The OELs for COEs exposure using the BBMD were 0.00170 mg/m^(3)for the total population,0.00158 mg/m^(3)for males,and 0.00174 mg/m^(3)for females.In possible risk obtained from animal studies(PROAST),the OELs of the total population,males,and females were 0.00184,0.00178,and 0.00192 mg/m^(3),respectively.Conclusion Based on our conservative estimate,the BMDL of mitochondrial damage caused by COEs is0.002 mg/m^(3).This value will provide a benchmark for determining possible OELs.展开更多
Partial sequences of the D-loop and the complete sequences of cytochrome b gene (1 140 bp) of the slow lorises (genus Nycticebus) were undertaken to investigate evolutionary relationships among species of Nycticebus.S...Partial sequences of the D-loop and the complete sequences of cytochrome b gene (1 140 bp) of the slow lorises (genus Nycticebus) were undertaken to investigate evolutionary relationships among species of Nycticebus.Sequence analysis results consistently provide new taxonomy evidence at the DNA level for supporting Ratajszczak and Groves’ viewpoint that N.intermedus is merely the adult of N.pygmaeus (Ratajszczak,1998;Groves,1971).Phylogenetic analysis was performed by means of the combined data and these two separate sequences data,respectively,by using various methods,supporting the same topology,in which genus Nycticebus was formed of two clusters.The first cluster was composed of N.pygmaeus,and the second cluster of N.coucang.It also could provide a new molecular genetic evidence to support the view that the genus comprises two species:N.coucang and N.pygmaeus.展开更多
AIM:To investigate the mutation in D-loop region of mitochondrial DNA in gastric cancer and its influence on the changes of reactive oxygen species (ROS) and cell cycle. METHODS: The D-loop region was amplified by PCR...AIM:To investigate the mutation in D-loop region of mitochondrial DNA in gastric cancer and its influence on the changes of reactive oxygen species (ROS) and cell cycle. METHODS: The D-loop region was amplified by PCR and sequenced.Reactive oxygen species and cell cycle were detected by flow cytometry in 20 specimens from gastric cancer and adjacent normal tissues.According to the sequence results,gastric cancer tissue was divided into mutation group and control group.Reactive oxygen species,apoptosis and proliferation in the two groups were compared. RESULTS:Among the 20 gastric cancer specimens, 18 mutations were identified in 7 patients,the mutation rate being 35%.There were four microsatellite instabilities in the mutations. No mutation was found in the adjacent tissues. Reactive oxygen species,apoptosis,and proliferation in the mutation group were all significantly higher than those in control group. CONCLUSION: Mutation in D-loop region plays a role in the genesis and development of gastric cancer.展开更多
Objective Background-study on genesis and development of tumor is mainly concentrated on gene mutation in nucleus.In recent years,however,the role of mitochondrial DNA(mtDNA) mutation in tumor genesis has been given m...Objective Background-study on genesis and development of tumor is mainly concentrated on gene mutation in nucleus.In recent years,however,the role of mitochondrial DNA(mtDNA) mutation in tumor genesis has been given more and more attention,which is the only extra-nucleus DNA in cells of higher animals.Carcinoma of the uterine cervix is a common tumor in gynecology,but there are few reports of mtDNA mutation in this area.The focus of this study was to investigate the mtDNA mutation in tumor tissues of cervical carcinomas and their relationship to tumorigenesis and tumor development.Methods The D-loop region of 24 cervical carcinomas together with the adjacent normal tissues were amplified by PCR and sequenced.Results Among the 24 cervical carcinomas,30 mutations in 9 patients′ specimen were identified with the mutations rate of 37.5%(9/24).There were 8 microsatellite instabilities among the mutations and 13 new polymorphisms which were not reported previously in the Genbank.Conclusions The D-loop region of mitochondrial DNA is a highly polymorphoric and mutable region and the mutation rate is relatively high in patients with cervical carcinomas.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 complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variation...The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variations and 57 haplotypes were detected, and the average number of nucleotide difference was 22.708, nucleotide diversity (π) was 0.0251 ± 0.00479, and haplotype diversity (Hd) was 0.888 ± 0.026, indicating very high genetic diversity in Chinese cattle breeds. In the Neighbor-Joining tree, 13 cattle breeds were divided into two main clades, Bos taurus and Bos indicus; new Clade Ill had only one sequence from Apeijiaza cattle breed in Tibet, which was similar to that of yak at a higher level than other cattle breeds, proving the introgression of genes from the yak. The proportions of Bos taurus and Bos indicus were 64.3 % and 35.7 % respectively in Xigaze Humped cattle breed, and 50.0% and 50.0% respectively in Apeijiaza cattle breed, which revealed that Tibet cattle included Bos indicus haplotypes. The importance of Yunnan cattle in the origin of Chinese cattle was also confirmed based on their abundant haplotypes. Then, a very special haplotype il discovered in 27 Chinese cattle breeds, including 11 breeds in this study and 16 breeds in the GenBank, played the role of a nucleus in Chinese zebu and was further discussed. At the same time, the construction of Chinese zebu core group based on haplotype il validated the distinct origin of Bos indicus in Tibet, which was different from that of the other cattle breeds with zebu haplotypes in China.展开更多
The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The c...The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The chloroplast trnL trnF region and one intra genic segment of the mitochondrial gene, Cox Ⅲ, were amplified from those of the parents and hybrids by PCR using gene specific primers. Cp and mtDNA polymorphisms of the amplified regions were detected between the parents after restriction digestions. Restriction fragment length polymorphism (RFLP) analysis revealed that all the F 1 individuals possessed Cox Ⅲ restriction fragment patterns (characteristic of the paternal parent Cryptomeria fortunei ) and the trnL trnF region (identical to the maternal parent Cunninghamia lanceolata ) showing that a different mode of inheritance for organelle DNA has occurred in the hybrids. Furthermore, the maternal inheritance of chloroplast DNA is reported here for the first time in coniferophyta.展开更多
To reveal the genetic structures and relationships of the four ethnic populations from the maternal inheritance and explore the origins and migrations of nationalities, the genetic polymorphism of mtDNA in Dong, Gelao...To reveal the genetic structures and relationships of the four ethnic populations from the maternal inheritance and explore the origins and migrations of nationalities, the genetic polymorphism of mtDNA in Dong, Gelao, Tujia, and Yi populations from Guizhou was studied by direct sequencing of hypervariable segment Ⅰ (HVS Ⅰ ) and PCR-RFLP of coding region. Thirty-seven (sub-) haplogroups were identified in the classification tree of mtDNA haplogroups. Haplogroup distributions and principal component (PC) analysis showed that the Dong has high frequencies of south-prevalent haplogroups, which indicates that it is a typically southern population. The Yi harbors high frequencies of the south-prevalent and northern-prevalent haplogroups, which demonstrates that it inherits the maternal characteristics from both southern and northern populations. The Yi and Gelao cluster together, the reason for which might be that their ancestries frequently underwent gene exchanges and mixtures.展开更多
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).
基金supported by the National Natural Science Foundation of China,No.81971269 (to DP)the Science and Technology Commission of Shanghai,No.YDZX20213100001003 (to DP)。
文摘In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.
基金supported by the Wenzhou Municipal Science and Technology Bureau(Y2020092)partly by the Key Specialty of Traditional Chinese Medicine of Zhejiang Province in the 13th Five-Year Plan period(Emergency Department).
文摘BACKGROUND:Pulmonary fibrosis(PF)is one of the main causes of death in patients with paraquat(PQ)poisoning.This study aimed to evaluate the relationship between mitochondrial fi ssion and oxidative stress in PQ-induced epithelial-mesenchymal transition(EMT)and PF.METHODS:C57BL/6 mice and MLE-12 cells were exposed to PQ to construct a PF model in vivo and in vitro.Histological changes in the lungs were examined by hematoxylin and eosin(H&E)staining.Mitochondrial morphology was detected by MitoTracker®Deep Red FM or transmission electron microscopy(TEM).Western blotting and immunofluorescence were used to determine the expression of protein.The migration ability of the cells was detected by the cell scratch test.Mitochondrial DNA(mtDNA)levels were assessed by real-time polymerase chain reaction(PCR).Enzyme-linked immunosorbent assay(ELISA)was applied to detect cytokine levels.Superoxide dismutase(SOD)activity and the levels of glutathione(GSH)and malondialdehyde(MDA)were detected by chemichromatometry.RESULTS:PQ exposure caused EMT and PF in vivo and in vitro.PQ destroyed mitochondrial structure and enhanced the expression of dynamin-related protein 1(Drp1),which were accompanied by oxidative stress.Inhibiting mitochondrial fission using mitochondrial division inhibitor-1(Mdivi-1),a selective inhibitor of Drp1,attenuated PQ-induced EMT and oxidative damage.Treatment with N-acetyl-L-cysteine(NAC),an antioxidant,reduced Drp1 expression,attenuated mitochondrial structure damage and inhibited PQ-induced EMT and PF.Both Mdivi-1 and NAC treatment markedly suppressed mtDNA release,the expression of Toll-like receptor 9(TLR9)and phosphorylation(P)-NF-κB p65 as well as cytokines(interleukin 6[IL-6],interleukin-1β[IL-1β],and tumor necrosis factor-α[TNF-α])production.CONCLUSION:Mutual promotion of mitochondrial fission and oxidative stress contributes to EMT in PQ-induced PF,which is associated with the mtDNA/TLR9/NF-κB pathway.
基金Supported by the Zhejiang Medical and Health Science and Technology Project,No.2023KY1126Suzhou Key Technologies Program,No.SKY2021063+3 种基金Jiangsu Province Social Development Project,No.BE2020764Suzhou Clinical Medical Center for Mood Disorders,No.Szlcyxzx202109Suzhou Clinical Key Disciplines for Geriatric Psychiatry,No.SZXK202116Suzhou Key Laboratory,No.SZS2024016。
文摘BACKGROUND Globally,the World Health Organization ranks major depressive disorder(MDD)as the leading cause of disability.However,MDD molecular etiology is still poorly understood.AIM To explore the possible association between mitochondrial ND6 T14502C mutation and MDD.METHODS Clinical data were collected from two pedigrees,and detailed mitochondrial genomes were obtained for the two proband members.The assessment of the resulting variants included an evaluation of their evolutionary conservation,allelic frequencies,as well as their structural and functional consequences.Detailed mitochondrial whole genome analysis,phylogenetic,and haplotype analysis were performed on the probands.RESULTS Herein,we reported the clinical,genetic,and molecular profiling of two Chinese families afflicted with MDD.These Chinese families exhibited not only a range of onset and severity ages in their depression but also extremely low penetrances to MDD.Sequence analyses of mitochondrial genomes from these pedigrees have resulted in the identification of a homoplasmic T14502C(I58V)mutation.The polymorphism is located at a highly conserved isoleucine at position 58 of ND6 and distinct mitochondrial DNA(mtDNA)polymorphisms originating from haplogroups M10 and H2.CONCLUSION Identifying the T14502C mutation in two individuals with no genetic relation who exhibit symptoms of depression provides compelling evidence that this mutation may be implicated in MDD development.Nonetheless,the two Chinese pedigrees that carried the T14502C mutation did not exhibit any functionally significant mutations in their mtDNA.Therefore,the phenotypic expression of the T14502C mutation related to MDD may be influenced by the nuclear modifier gene(s)or environmental factors.
基金The National Natural Science Foundation of China under contract Nos 32170536 and 31672257。
文摘Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.
基金Supported by the Science and Technology Plan of Jinhua City,No.2020-3-026。
文摘BACKGROUND Here,we present a unique case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes(MELAS)syndrome,which initially appeared to be autoimmune encephalitis and was ultimately confirmed as MELAS with the mitochondrial DNA 3243A>G mutation.CASE SUMMARY A 58-year-old female presented with acute-onset speech impediment and auditory hallucinations,symmetrical bitemporal lobe abnormalities,clinical and laboratory findings,and a lack of relevant prodromal history,which suggested diagnosis of autoimmune encephalitis.Further work-up,in conjunction with the patient’s medical history,family history,and lactate peak on brain lesions on magnetic resonance imaging,suggested a mitochondrial disorder.Mitochondrial genome analysis revealed the m.3243A>G variant in the MT-TL1 gene,which led to a diagnosis of MELAS syndrome.CONCLUSION This case underscores the importance of considering MELAS as a potential cause of autoimmune encephalitis even if patients are over 40 years of age,as the symptoms and signs are atypical for MELAS syndrome.
基金supported by the National Natural Science Foundation of China[grant numbers:NSFC81872597,81001239]。
文摘Objective The study aimed to estimate the benchmark dose(BMD)of coke oven emissions(COEs)exposure based on mitochondrial damage with the mitochondrial DNA copy number(mtDNAcn)as a biomarker.Methods A total of 782 subjects were recruited,including 238 controls and 544 exposed workers.The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction.Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95%confidence lower limit(BMDL).Results The mtDNAcn of the exposure group was lower than that of the control group(0.60±0.29 vs.1.03±0.31;P<0.001).A dose-response relationship was shown between the mtDNAcn damage and COEs.Using the Benchmark Dose Software,the occupational exposure limits(OELs)for COEs exposure in males was 0.00190 mg/m^(3).The OELs for COEs exposure using the BBMD were 0.00170 mg/m^(3)for the total population,0.00158 mg/m^(3)for males,and 0.00174 mg/m^(3)for females.In possible risk obtained from animal studies(PROAST),the OELs of the total population,males,and females were 0.00184,0.00178,and 0.00192 mg/m^(3),respectively.Conclusion Based on our conservative estimate,the BMDL of mitochondrial damage caused by COEs is0.002 mg/m^(3).This value will provide a benchmark for determining possible OELs.
文摘Partial sequences of the D-loop and the complete sequences of cytochrome b gene (1 140 bp) of the slow lorises (genus Nycticebus) were undertaken to investigate evolutionary relationships among species of Nycticebus.Sequence analysis results consistently provide new taxonomy evidence at the DNA level for supporting Ratajszczak and Groves’ viewpoint that N.intermedus is merely the adult of N.pygmaeus (Ratajszczak,1998;Groves,1971).Phylogenetic analysis was performed by means of the combined data and these two separate sequences data,respectively,by using various methods,supporting the same topology,in which genus Nycticebus was formed of two clusters.The first cluster was composed of N.pygmaeus,and the second cluster of N.coucang.It also could provide a new molecular genetic evidence to support the view that the genus comprises two species:N.coucang and N.pygmaeus.
文摘AIM:To investigate the mutation in D-loop region of mitochondrial DNA in gastric cancer and its influence on the changes of reactive oxygen species (ROS) and cell cycle. METHODS: The D-loop region was amplified by PCR and sequenced.Reactive oxygen species and cell cycle were detected by flow cytometry in 20 specimens from gastric cancer and adjacent normal tissues.According to the sequence results,gastric cancer tissue was divided into mutation group and control group.Reactive oxygen species,apoptosis and proliferation in the two groups were compared. RESULTS:Among the 20 gastric cancer specimens, 18 mutations were identified in 7 patients,the mutation rate being 35%.There were four microsatellite instabilities in the mutations. No mutation was found in the adjacent tissues. Reactive oxygen species,apoptosis,and proliferation in the mutation group were all significantly higher than those in control group. CONCLUSION: Mutation in D-loop region plays a role in the genesis and development of gastric cancer.
文摘Objective Background-study on genesis and development of tumor is mainly concentrated on gene mutation in nucleus.In recent years,however,the role of mitochondrial DNA(mtDNA) mutation in tumor genesis has been given more and more attention,which is the only extra-nucleus DNA in cells of higher animals.Carcinoma of the uterine cervix is a common tumor in gynecology,but there are few reports of mtDNA mutation in this area.The focus of this study was to investigate the mtDNA mutation in tumor tissues of cervical carcinomas and their relationship to tumorigenesis and tumor development.Methods The D-loop region of 24 cervical carcinomas together with the adjacent normal tissues were amplified by PCR and sequenced.Results Among the 24 cervical carcinomas,30 mutations in 9 patients′ specimen were identified with the mutations rate of 37.5%(9/24).There were 8 microsatellite instabilities among the mutations and 13 new polymorphisms which were not reported previously in the Genbank.Conclusions The D-loop region of mitochondrial DNA is a highly polymorphoric and mutable region and the mutation rate is relatively high in patients with cervical carcinomas.
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This work was supported by the Project of Measurement of Genetic Distances Among Chinese Indigenous Bovine Breeds(Agri-culture Finance Department[2002]No.9).In:Program of Preservation and Utilization for Agriculture,Animal Husbandry and Forestry Germplasm Resources,Ministry of Agriculture.
文摘The complete mitochondrial D-loop region from 123 individuals in 12 Chinese cattle breeds and two individuals in Germany Yellow cattle breed was sequenced and analyzed. The results were shown as follows: 93 variations and 57 haplotypes were detected, and the average number of nucleotide difference was 22.708, nucleotide diversity (π) was 0.0251 ± 0.00479, and haplotype diversity (Hd) was 0.888 ± 0.026, indicating very high genetic diversity in Chinese cattle breeds. In the Neighbor-Joining tree, 13 cattle breeds were divided into two main clades, Bos taurus and Bos indicus; new Clade Ill had only one sequence from Apeijiaza cattle breed in Tibet, which was similar to that of yak at a higher level than other cattle breeds, proving the introgression of genes from the yak. The proportions of Bos taurus and Bos indicus were 64.3 % and 35.7 % respectively in Xigaze Humped cattle breed, and 50.0% and 50.0% respectively in Apeijiaza cattle breed, which revealed that Tibet cattle included Bos indicus haplotypes. The importance of Yunnan cattle in the origin of Chinese cattle was also confirmed based on their abundant haplotypes. Then, a very special haplotype il discovered in 27 Chinese cattle breeds, including 11 breeds in this study and 16 breeds in the GenBank, played the role of a nucleus in Chinese zebu and was further discussed. At the same time, the construction of Chinese zebu core group based on haplotype il validated the distinct origin of Bos indicus in Tibet, which was different from that of the other cattle breeds with zebu haplotypes in China.
文摘The inheritance of mitochondrial (mt) DNA and chloroplast (cp) DNA was investigated in intergeneric hybrids from crossing between Cunninghamia lanceolata (Lamb.) Hook. and Cryptomeria fortunei Hooibrenk. The chloroplast trnL trnF region and one intra genic segment of the mitochondrial gene, Cox Ⅲ, were amplified from those of the parents and hybrids by PCR using gene specific primers. Cp and mtDNA polymorphisms of the amplified regions were detected between the parents after restriction digestions. Restriction fragment length polymorphism (RFLP) analysis revealed that all the F 1 individuals possessed Cox Ⅲ restriction fragment patterns (characteristic of the paternal parent Cryptomeria fortunei ) and the trnL trnF region (identical to the maternal parent Cunninghamia lanceolata ) showing that a different mode of inheritance for organelle DNA has occurred in the hybrids. Furthermore, the maternal inheritance of chloroplast DNA is reported here for the first time in coniferophyta.
基金This work was supported by the National Natural Science Foundation of China (No. 39560035).
文摘To reveal the genetic structures and relationships of the four ethnic populations from the maternal inheritance and explore the origins and migrations of nationalities, the genetic polymorphism of mtDNA in Dong, Gelao, Tujia, and Yi populations from Guizhou was studied by direct sequencing of hypervariable segment Ⅰ (HVS Ⅰ ) and PCR-RFLP of coding region. Thirty-seven (sub-) haplogroups were identified in the classification tree of mtDNA haplogroups. Haplogroup distributions and principal component (PC) analysis showed that the Dong has high frequencies of south-prevalent haplogroups, which indicates that it is a typically southern population. The Yi harbors high frequencies of the south-prevalent and northern-prevalent haplogroups, which demonstrates that it inherits the maternal characteristics from both southern and northern populations. The Yi and Gelao cluster together, the reason for which might be that their ancestries frequently underwent gene exchanges and mixtures.