Chronic polyarthritis caused by mammalian DNA that escapes from degradation in macrophages

A large amount of chromosomal DNA is degraded during programmed cell death and definitive erythropoiesis. DNase II is an enzyme that digests the chromosomal DNA of apoptotic cells and nuclei expelled from erythroid precursor cells after macrophages have engulfed them. Here we show that DNase II-/-IFN-IR-/- mice and mice with an induced deletion of the DNase II gene develop a chronic polyarthritis resembling human rheumatoid arthritis. A set of cytokine genes was strongly activated in the affected joints of these mice, and their serum contained high levels of anti-cyclic citrullinated peptide antibody, rheumatoid factor and matrix metalloproteinase-3. Early in the pathogenesis, expression of the gene encoding tumour necrosis factor (TNF)-alpha was upregulated in the bone marrow, and administration of anti-TNF-alpha antibody prevented the development of arthritis. These results indicate that if macrophages cannot degrade mammalian DNA from erythroid precursors and apoptotic cells, they produce TNF-alpha, which activates synovial cells to produce various cytokines, leading to the development of chronic polyarthritis.     

小灵猫华东亚种线粒体DNA限制性位点图

提纯了小灵猫华东亚种（ＶｉｖｅｒｒｉｃｕｌａｉｎｄｉｃａｐａｌｉｄａＧｒａｙ）的肝脏ｍｔＤＮＡ．用ＢａｍＨⅠ、ＢｇｌⅡ、ＥｃｏＲⅤ、ＨｐａⅠ、ＫｐｎⅠ、ＭｌｕⅠ、ＰｓｔⅠ、ＰｖｕⅡ、ＳａｃⅡ、ＳａｌⅠ和ＸｈｏⅠ等１１种识别６碱基对的限制性内切酶对小灵猫华东亚种ｍｔＤＮＡ进行消化分析，１１种限制性内切酶均有１～５个位点；根据单酶消化和双酶消化片段的数目和分子量，构建了小灵猫华东亚种ｍｔＤＮＡ限制性位点图     

Mitochondrial DNA and human evolution

Mitochondrial DNAs from 147 people, drawn from five geographic populations have been analysed by restriction mapping. All these mitochondrial DNAs stem from one woman who is postulated to have lived about 200,000 years ago, probably in Africa. All the populations examined except the African population have multiple origins, implying that each area was colonised repeatedly.     

滑鼠蛇肝线粒体DNA的制备及性质测定

报导了用蛇肝脏制备线粒体DNA的简便方法。电镜分析结果表明,滑鼠蛇肝mt DNA为环状分子,周长5.23μm。限制性内切酶PstI,BamHI和EcoRI在滑鼠蛇肝mtDNA上分别有2、3和4个点切。根据各酶切片段的大小测得mt DNA的平均分子量为16.91kb或10.85×10~6 dalton。     

新疆察吾呼沟古代居民线粒体DNA序列多态性分析

从距今2 500～3 000年的新疆察吾呼沟墓地的9例古代人骨中成功地提取出古DNA分 子. 用4对套叠引物对线粒体DNA高可变Ⅰ区进行了PCR扩增和测序, 得到9个364　bp的线粒 体序列. 从GenBank搜索其共享序列并与欧洲、 亚洲序列进行系统发育分析, 结果表明, 早在青铜至早期铁器时代, 在我国新疆天山中部地区已经有蒙古人种存在. 察吾呼沟古代 居民应是一个欧洲和东亚人种混合的古代群体.     

羚牛线粒体DNA和系统进化研究

用8种限制酶分析了5种牛科动物，羚牛、黄牛、水牛、绵羊和山羊的线粒体DNA的多态性。依据数学模型计算这5种动物间的遗传距离，在此基础上构建了UPG和NJ两种分子系统进化树。结果表明：羚牛与牛和羊的分化时间分别为4．02Ma和3．72Ma，因此将羚牛归入羊亚科较为合理。     

三索线蛇与过树容蛇肝线粒体DNA的纯化与限制酶图谱

用Sepharose 4B凝胶柱过滤和NaCl离心法纯化了三索线蛇及过树容蛇肝线粒体DNA(mtDNA),它们的分子长度分别为17.75kb及19.70kb。分别用EcoRⅠ,XbaⅠ,BamHⅠ及BglⅡ等4种限制酶消化这两种mtDNA,结果表明:EcoRⅠ,XbaⅠ,BamHⅠ和BglⅡ在三索线蛇肝mtDNA上分别有1,1,2及3个切点;在过树容蛇肝mtDNA上各有4,1,1和2个切点。根据mtDNA的单酶、双酶和部份酶解片段的分析,建立了三索线蛇及过树容蛇肝mtDNA的限制酶图谱。     

丰鲤及其双亲线粒体DNA限制性酶切图谱的研究

采用密度梯度离心及RNase消化法制备并纯化了丰鲤(Fengcarp)、兴国红鲤(Xingguoredcarp)及散鳞镜鲤(Scatterscaledmirrorcarp)的肝脏线粒体DNA,用10种限制性内切酶HindIII、EcoRI、BamHI、XbaI、XhoI、PstI、BglII、SalI、BglI、PvuII进行了分析.丰鲤mtDNA相对分子质量约为9 88×106,大小约为16 49kb;兴国红鲤mtDNA相对分子质量约为9 89×106,大小约为16 50kb;散鳞镜鲤mtDNA相对分子质量约为9 87×106,大小为16 48kb.HindIII、EcoRI、BglI、BamHI、XbaI、XhoI、SalI、BglII、PstI及PvuII在丰鲤、兴国红鲤、散鳞镜鲤线粒体DNA分子上均分别有6、4、3、3、3、1、1、0、1和4个切点.根据单酶切及双酶切结果,构建了丰鲤、兴国红鲤、散鳞镜鲤mtDNA9种酶的限制性酶切图谱,结果表明丰鲤、兴国红鲤及散鳞镜鲤mtDNA间缺乏变异性.     

一母系遗传非综合征耳聋家系的线粒体DNA突变分析

在问卷调查及家系随访的基础上,在安徽省淮北市收集到一母系遗传非综合征耳聋家系,利用聚合酶链式反应-限制片段长度多态性分析(PCR-RFLP)和测序技术,检测了该家系成员线粒体DNA(mtDNA)上可导致非综合征耳聋的两个突变热点处(12S rRNA基因上的1 555位点和tRNASer(UCN)基因上的7 445位点)的碱基变化,发现该家系所有母系成员的mtDNA上都有A1555G同质型突变,但7 445位点无异常;进而对该家系两个表型明显不同母系成员(一例具有先天性耳聋表型,另一例听力正常)的mtDNA进行全长测序,结果未在mtDNA上发现除A1555G以外的其他位点突变,只发现了27处多态性序列变化,且两成员的mtDNA无序列差异.说明mtDNA上的A1555G同质型突变是该家系部分母系成员致聋的分子生物学基础之一;推测该家系A1555G突变携带者临床表型的差异可能与mtDNA多态性无关,而更可能是核修饰基因与A1555G突变协同作用的结果.     

中国斑腿蝗科线粒体基因的分子系统学研究(英文)

使用线粒体基因COⅠ,COⅡ,Cytb分析并建立中国斑腿蝗科部分种属的系统发育关系,其中对7个新种(Apalacris eminifronta,Caryanda pseudodentata,Caryanda bannaensis,Caryanda ruiliensis,Longchuanacris fui,Longchuanacris xiaoheis-hanensis,Podismodes dabieshanensis)的归属从分子角度也做了讨论。本研究将实验所获得的56条序列与NCBI中所收录的斑腿蝗科序列进行联合分析,采用最大似然法、贝叶斯推论等系统分析方法并综合P距离进行分析,最终得出以下几点结论:①龙川蝗属Longchuanaceis Zheng et Fu划归卵翅蝗亚科Caryandinae;②蹦蝗属Sinopodisma Chang、云秃蝗属Yunnanacris Chang均为华秃蝗属Podismodes Ramme的同物异名;③不支持Storozhenko将豫蝗属Yupodisma Zhang et Xia并入安秃蝗属AnapodismaDovnar-Zapolskii,从本研究所建的系统发育树来看,豫蝗属仍应作为秃蝗亚科Podisminae的一个独立属;④前人利用形态特征鉴定的七个新种与分子系统发育分析结果一致,新种独立有效。     

暗纹东方鲀线粒体ND1及其侧翼tRNA基因的克隆及序列分析

利用提取纯化的暗纹东方纯（rakifugu fasciatoz）肝脏的mtDNA为模板，按红鳍东方纯（rakifugu rubripes）mtDNA序列设计合成特异引物进行PCR扩增，首次克隆并测定了暗纹东方纯mtDNA的ND1亚基及其侧翼的tRNA基因。运用DNA分析软件，对暗纹东方纯与GenBank中选取的几种同目的鱼类的相应序列进行比较分析，显示暗纹东方纯与这些鱼类的各个相应基因具有较高的同源性。利用分子生物学相关软件，对暗纹东方纯及与其同目的6种鱼的ND1基因序列建立NJ和MP分子进化树，并与传统的分类地位进行比较，结果表明与传统的分类地位基本吻合。3个tRNA基因含有69～71个碱基，推定了各个tRNA的二级结构，均具有较为典型的三叶草型结构。     

淡水鱼类线粒体DNA D-loop基因的引物设计和应用

 线粒体DNA测序已广泛应用于鉴定和区分种类以及解决系统进化关系问题。本文选取已测定的主要淡水鱼类的线粒体DNA D-loop基因序列进行同源性比较,寻找保守序列,利用简并性原则设计一对通用的简并引物。利用设计的引物对广东省珠江流域主要的淡水鱼类线粒体DNA D-loop控制区基因进行扩增,均能获得单一的目的DNA片断,特异性扩增产物大小为1 kb左右。经测序及与GenBank同源序列的比较,证实为包含线粒体控制区全序列的扩增产物。本研究所设计的引物和应用的方法可以快速地同时对多种鱼类进行大规模的遗传背景分析,鉴定某些难于鉴别的近缘物种,为我国鱼类的种类鉴定、地理种群鉴别及种质资源的评估提供重要的工具。     

猛禽和夜鹰类的线粒体DNA序列比较和分子进化关系的研究

测定和比对了隼形目、鸮形目、夜鹰目的12SrRNA基因片段,长度为415 bp.使用MEGA2.1软件构建分子系统树并分析其系统进化关系.数据显示,该基因片段的DNA序列变异丰富,转换和颠换数未随着遗传距离的增加而出现饱和现象,反映出较高真实水平的鸟类系统发育关系.重建系统进化树表明:与隼形目隼科相比,隼形目鹰科与鸮形目、夜鹰目的亲缘关系更近,提示了隼形目隼科和鹰科之间可能存在着较大的遗传变异;与夜鹰目相比,鸮形目和隼形目鹰科鸟类的亲缘关系较近,与传统分类观点相同,不支持将鸮形目和夜鹰目合并为鸮形目的观点.     

猛禽和夜鹰类的线粒体DNA序列比较和分子进化关系的研究

测定和比对了隼形目、鸮形目、夜鹰目的12SrRNA基因片段，长度为415bp．使用MEGA2．1软件构建分子系统树并分析其系统进化关系．数据显示，该基因片段的DNA序列变异丰富，转换和颠换数未随着遗传距离的增加而出现饱和现象，反映出较高真实水平的鸟类系统发育关系．重建系统进化树表明：与隼形目隼科相比，隼形目鹰科与鸮形目、夜鹰目的亲缘关系更近，提示了隼形目隼科和鹰科之间可能存在着较大的遗传变异；与夜鹰目相比，鸮形目和隼形目鹰科鸟类的亲缘关系较近，与传统分类观点相同，不支持将鸮形目和夜鹰目合并为鸮形目的观点．     

Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, China

In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia. China to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modern horse clusters which were closely related to them representing a certain geographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified, which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in China.     

Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, China

In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia. China to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modern horse clusters which were closely related to them representing a certain geographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified, which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in China.     

HDACs link the DNA damage response, processing of double-strand breaks and autophagy

Protein acetylation is mediated by histone acetyltransferases (HATs) and deacetylases (HDACs), which influence chromatin dynamics, protein turnover and the DNA damage response. ATM and ATR mediate DNA damage checkpoints by sensing double-strand breaks and single-strand-DNA-RFA nucleofilaments, respectively. However, it is unclear how acetylation modulates the DNA damage response. Here we show that HDAC inhibition/ablation specifically counteracts yeast Mec1 (orthologue of human ATR) activation, double-strand-break processing and single-strand-DNA-RFA nucleofilament formation. Moreover, the recombination protein Sae2 (human CtIP) is acetylated and degraded after HDAC inhibition. Two HDACs, Hda1 and Rpd3, and one HAT, Gcn5, have key roles in these processes. We also find that HDAC inhibition triggers Sae2 degradation by promoting autophagy that affects the DNA damage sensitivity of hda1 and rpd3 mutants. Rapamycin, which stimulates autophagy by inhibiting Tor, also causes Sae2 degradation. We propose that Rpd3, Hda1 and Gcn5 control chromosome stability by coordinating the ATR checkpoint and double-strand-break processing with autophagy.