Sequence Analysis of Mitochondrial DNA D-loop Region in Xinjiang Goose

[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）.

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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.

安徽新安江水牛mtDNA D-Loop区遗传多样性与系统进化研究

试验旨在分析安徽省黄山市新安江流域上游地区新安江水牛群体的分子遗传特性,探究其母系起源与遗传多样性。利用PCR扩增和测序技术测定28头新安江水牛的mtDNA D-Loop序列,下载GenBank数据库中24个中国水牛群体的693条D-Loop序列,利用生物信息学分析其遗传多样性,构建Neighbor-joining系统发生树和Media-joining网络,探索不同水牛群体的遗传距离。结果显示,28头新安江水牛的mtDNA D-Loop序列共有117个变异位点,构成25种单倍型,其核苷酸多样性为0.02602±0.00303,单倍型多样性为0.989±0.014。新安江水牛群体的变异性水平与中国其他水牛群体接近。N-J系统进化树显示,新安江水牛25个单倍型分为A、B两个支系,具有A支系和B支系2个母系来源,其中A支系占据主导地位。Media-joining进化网络显示,中国水牛主要为沼泽型水牛,分为沼泽型水牛A支系和B支系,B支系又分为b1亚支系和b2亚支系。综上,新安江水牛群体变异水平与中国其他地方水牛群体接近,群体遗传多样性丰富;且新安江水牛属于沼泽型水牛,具有2个线粒体母系来源,与我国其他地方水牛群体具有一定的遗传距离。

青海骆驼线粒体DNA D-loop区遗传多样性研究

旨在研究青海骆驼遗传多样性,揭示青海骆驼的母系起源进化。采集柴达木地区3个青海骆驼类群耳组织样品88份并提取基因组DNA,利用PCR扩增和基因测序分析线粒体DNA D-loop序列,并与蒙古、内蒙古双峰驼进行比较。结果表明:D-loop序列中共检测到96个多态位点,定义了27种单倍型。3个青海骆驼类群占有16个单倍型,而蒙古双峰驼独有7个单倍型,内蒙古双峰驼独有4个单倍型。系统发育分析显示出两个独立的分支:第一支为青海骆驼3个类群与蒙古双峰驼,且德令哈双峰驼与其他两个类群间存在明显界限;第二支为内蒙古双峰驼。青海骆驼与内蒙古双峰驼的遗传距离均较远,但与蒙古双峰驼的遗传距离较近。因此,青海骆驼母系起源更倾向于蒙古双峰驼而非内蒙古双峰驼。

Mutual promotion of mitochondrial fi ssion and oxidative stress contributes to mitochondrial-DNAmediated infl ammation and epithelial-mesenchymal transition in paraquat-induced pulmonary fibrosis

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.

Molecular phylogenetics and population demographic history of Amphioctopus fangsiao,inferred from mitochondrial and microsatellite DNA markers

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.

Late-onset mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome with mitochondrial DNA 3243A>G mutation masquerading as autoimmune encephalitis:A case report

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.

Benchmark Dose Assessment for Coke Oven Emissions-Induced Mitochondrial DNA Copy Number Damage Effects

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.

Molecular Phylogeny of Slow Lorises (Nycticebus) Revealed by D-loop Sequences and Complete Cytochrome b Gene Sequences of Mitochondrial DNA

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.

Mutation in D-loop region of mitochondrial DNA in gastric cancer and its significance

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.

A Study on the D-loop Region of Mitochondrial DNA (mtDNA) Mutation in Cervical Carcinomas

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.

Mutations in the D-loop region of mitochondrial DNA in 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.

基于线粒体DNAD-loop全序列的麒麟鸡遗传多样性研究

【目的】从线粒体DNA(mtDNA)D-loop全序列角度评估麒麟鸡的遗传多样性水平,以期阐明麒麟鸡的品种形成。【方法】通过PCR产物直接测序法对麒麟鸡保种群的黄羽、白羽和黑羽3个资源群及8个地方鸡品种进行mtDNA D-loop全序列测定,分析遗传变异,并进行中性检测,构建单倍型中介网络图,探究麒麟鸡的群体历史。【结果】麒麟鸡mtDNAD-loop全序列为1231~1232bp,C+G含量(39.8%)低于T+A含量(60.2%),总体核苷酸多样性为0.00630±0.00054,明显高于其他8个地方鸡品种。3个资源群黄羽、白羽和黑羽麒麟鸡的单倍型多样性分别为0.777±0.076、0.816±0.060、0.710±0.057,核苷酸多样性分别为0.00699±0.00115、0.00662±0.00090、0.00546±0.00062,遗传多样性水平基本上与群体规模呈正相关。麒麟鸡与8个地方鸡的双参数遗传距离为0.008~0.009,净遗传距离为0.003~0.005,均大于其他地方鸡之间的遗传距离。90份麒麟鸡样本共检测到45个突变位点,定义了17个单倍型,其中独享型单倍型9个,单倍型多样性为0.773±0.039。黄羽、白羽和黑羽麒麟鸡的单倍型数量分别为12、7、5个。8个地方鸡品种定义了19个单倍型,其中河田鸡的单倍型数量最多(8个),宁都黄鸡的最少(3个),没有与麒麟鸡共享的单倍型。中性检测结果显示,除了黑羽麒麟鸡外,供试鸡种在品种水平上近期均未经历明显的种群扩张。麒麟鸡单倍型类群主要分布在进化枝A、B、C和E,优势单倍型类群是B(30.0%)和E(64.4%);8个地方鸡单倍型类群主要为A和B。【结论】独特的单倍型提示麒麟鸡具有独立的品种形成历史,相对较高的遗传多样性水平将有利于其保护和利用工作的开展。

苏姜猪mtDNA D-loop序列的遗传多样性分析

【目的】通过对苏姜猪线粒体DNA(mtDNA)D-loop高变区Ⅰ的序列扩增测序,探究苏姜猪种群的种质资源特性和遗传多样性。【方法】采集苏姜猪核心群100头经产母猪耳组织,提取DNA后扩增苏姜猪核心群母猪mtDNA D-loop高变区Ⅰ的基因片段并测序,运用NCBI在线BLAST对测序序列与参考序列进行比对、校正并寻找同源序列,确定mtDNA D-loop高变区Ⅰ序列的长度和位置;使用DnaSP v.5.10.1软件统计获得群体中核苷酸多态位点和变异位点数量,分析单倍型多样度(Hd)、核苷酸多样性(Pi)、平均核苷酸差异度(K)等参数;使用Mega 7.0软件对不同单倍型进行基于Kimura’s 2-prarmetermodel的遗传距离计算,采用邻接法(Neighbor-Joining,NJ)对苏姜猪的4个单倍型、17个中国地方猪种、欧洲家猪(登录号:AF034253.1)的mtDNA D-loop高变区Ⅰ序列构建系统发育树。【结果】对100头苏姜猪的mtDNA D-loop序列高变区Ⅰ进行扩增测序,获得长度为429 bp的有效序列,获得的序列中,AT含量为63.1%,GC含量为36.9%;中性检验Tajima’s D值为-1.80517(P<0.05),证实苏姜猪种群显著性偏离中性检验;被测序列中检测到19个变异位点,定义了4个单倍型,单倍型多样度为0.578,核苷酸多样性为0.0032;种群内4个单倍型之间的平均遗传距离在0.004~0.031之间。系统发育树结果显示,群体分为国内和国外2个类群,苏姜猪4个单倍型都聚集在国内分支上,其中单倍型H2和二花脸猪聚为一类,单倍型H4和姜曲海、皖南花猪等聚为一类。【结论】苏姜猪种群mtDNA D-loop高变区Ⅰ多态位点比例高,单倍型多样度高,核苷酸多样性低;苏姜猪群体内优势单倍型的遗传距离较近,占比较高,反映出苏姜猪群体母系来源较少。

Genetic Variation of Mitochondrial D-loop Region and Evolution Analysis in Some Chinese Cattle Breeds

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.

Inheritance of Chloroplast and Mitochondrial DNA in Chinese Fir (Cunninghamia lanceolata)

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.

线粒体DNA D-Loop区突变与弱精症的相关性

目的:探讨精子线粒体DNAD-Loop区基因突变和弱精症的相关性。方法:收集2019年7月至2021年3月温州市中医院诊治的134例弱精症患者(弱精症组)和129例同期健康男性(对照组)的精液,提取精子细胞DNA,采用聚合酶链反应(PCR)对线粒体DNA D-Loop区进行扩增并测序,测序结果与剑桥标准序列(r CRS)进行比对,分析弱精症患者精子细胞线粒体DNA D-Loop区的基因突变情况。结果:两组中发生率>5%的突变有62种,大部分位于HV-1区和HV-2区(87.78%),突变类型以替换突变为主(87.03%)。分析显示,有11种突变在弱精症组和对照组之间的差异有统计学意义(P<0.05),这些突变可能增加或降低弱精症风险。结论:精子线粒体DNA D-Loop区具有较高突变率,可能在弱精症发生发展中发挥重要作用。

Genetic Polymorphism of Mitochondrial DNA in Dong,Gelao,Tujia,and Yi Ethnic Populations from Guizhou,China

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.

视神经脊髓炎谱系疾病患儿外周血线粒体DNA及细胞因子的作用研究

目的基于外周血线粒体DNA-TLR9信号通路探讨视神经脊髓炎谱系疾病中线粒体DNA(mtDNA)和细胞因子的功能作用及其影响机制。方法选取2020年12月-2023年12月就诊于本院的20例视神经脊髓炎谱系疾病患者为病例组,并选取同期性别与年龄相似的正常体检的健康儿童20例为对照组。采用化学发光免疫分析法(CBA法)测定病例组患者血清及脑脊液中水通道蛋白4抗体(AQP4-Ab)和髓鞘少突胶质细胞糖蛋白抗体(MOG-Ab)的表达。利用酶联免疫吸附试验(ELISA)对比两组血清中白细胞介素-6(IL-6)、白细胞介素-1(IL-1)、白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)的水平。使用线粒体DNA抽提工具包检测外周血线粒体DNA拷贝数,并对两组进行比较。结果病例组中外周血线粒体DNA拷贝数(0.80±0.02)显著高于对照组(0.78±0.02),差异有统计学意义(t=3.614,P<0.01)。与对照组比较,病例组中IL-6及IL-1β水平有所升高,但差异无统计学意义(P>0.05);与对照组比较,病例组中IL-1及TNF-α水平明显升高,差异有统计学意义(P<0.05)。与AQP4-IgG阴性组比较,AQP4-IgG阳性组TNF-α水平降低,扩展残疾状况量表(EDSS)评分增高,差异有统计学意义(P<0.05);与AQP4-IgG阴性组比较,AQP4-IgG阳性组IL-6、IL-1β、mtDNA降低,IL-1升高,但差异无统计学意义(P>0.05)。结论视神经脊髓炎谱系疾病的发病机制可能涉及线粒体DNA和细胞因子,这些因子通过天然免疫反应的路径可能对疾病进程产生影响。

转录因子MYB转录调控MTFR2通过DNA损伤修复促进胃癌细胞化疗耐药性

目的探究v-myb禽成髓细胞病病毒癌基因同源物(MYB)转录调控线粒体裂变调节因子2(MTFR2)对胃癌(GC)细胞顺铂(DDP)耐药性的影响及分子作用机制。方法TCGA数据库分析GC中差异mRNA并预测上游调控分子,qRT-PCR检测MTFR2和MYB的表达,双荧光素酶和染色质免疫共沉淀(ChIP)实验验证MTFR2和MYB的调控关系,细胞计数盒8(CCK-8)检测细胞活力并计算IC_(50)值,流式细胞术检测细胞周期和细胞凋亡,彗星实验检测DNA损伤,蛋白质免疫印迹法检测DNA损伤相关蛋白(γ-H2AX、ATM、p-ATM)的表达。结果MTFR2在GC组织和细胞中显著高表达,敲低MTFR2能够降低细胞增殖,阻滞S期,诱导细胞凋亡,促进DNA损伤和DDP敏感性。生信预测MTFR2存在上游转录因子MYB,MYB在GC组织和细胞中的表达显著上调,双荧光素酶和ChIP验证了MTFR2启动子区域与MYB的结合关系。回复实验发现进一步过表达MTFR2能够逆转敲低MYB对GC细胞增殖和DDP耐药性的抑制作用。结论MYB上调MTFR2的表达通过DNA损伤途径促进GC细胞增殖和DDP耐药,表明靶向MYB/MTFR2调控轴可能是克服GC DDP耐药性的潜在途径。