神经肌肉性疾病患者线粒体DNA突变的分析 Analysis on the Mitochondrial DNA of Patients with Neuromuscular Diseases

为了探讨神经肌肉性疾病的发病与线粒体DNA突变的关系,采用PCR技术检测了 20例患有不同神经肌肉性疾病儿童的外周血和骨骼肌细胞中的线粒体DNA(mtDNA),发现其中6例患儿有mtDNA缺失,其中1例至少有2968bp片段的缺失, 另5例至少有2000bp片段的缺失,此缺失区位于线粒体呼吸链复合物1、 4、5、编码区,表明该突变对神经肌肉性疾病的发生有一定作用。 Abstract:To understand the relation to mechanism of neuromuscular disease and mtDNA mutation,using PCR technique,we investigated blood and /or skeletal muscle of 20 patients with neuromuscular diseases.A deletion in the length of 2000~2968bp was found in blood mitochondrial DNA of 6 patients with neuromuscular disease.The deletion region partially lies in the coding region of resoiratony chain complex 1,4,5.It is suggested that this mutation ois related with neuromuscular diseases.     

线粒体DNA缺失与神经肌肉性疾病的研究

应用PCR技术对13例神经肌肉疾病患者的线粒体DNA缺失进行了研究。结果表明,其中二例肢带型肌营养不良症患者骨骼肌组织和一例帕金森氏病患者的血细胞线粒体DNA中存在至少526bp的缺失。提示线粒体突变在一些神经肌肉性疾病的发生中起一定的作用。 Abstract: Using PCR technique,we analysed the skeletal muscle and blood of 13 patients with neuromuscular disaeases.The results show that a mutant mitochondrial DNA with at least 526bp deletion exits in the skeletal muscles of 2 patients with Erb muscular dystrophy and in the blood of a patients with Parkinson’s disease.From our results,mitochondrial DNA mutations could be an important contributory factor to neuromuscular diseases.     

肥厚型心肌病患者心肌mtDNA大片段缺失的探讨

应用Long PCR及Primer Shift Long PCR 技术对3例肥厚型心肌病(HCM）患者和10例正常引产胎儿的13份心肌标本予以线粒体 DNA缺失检测,结果在1例HCM患者心肌线粒体DNA中发现约5.0kb缺失,而在正常引产胎儿的标本未见该缺失,提示HCM的发生可能与mtDNA缺失相关。 Astract　Using long PCR and primer shift long PCR techniques, we analyzed the mitochondrial DNA (mtDNA) isolated from the heart muscles of 3 hypertrophic cardiomyopathy (HCM) patients and 10 normal abortive fetuses. Almost 5.0kb deletion was found in the heart mtDNA of one HCM patient, while no deletion was detected in that of 10 fetuses. It is concluded that HCM may correlate with mtDNA deletion.     

线粒体基因突变与NIDDM发生的关系

采用PCR-SSCP、PCR-RFLP及PCR产物直接测序等技术对90例NIDDM(即非胰岛素依赖型糖尿病)及80例正常对照个体的血细胞线粒体DNA进行了突变分析。结果在2例患者中发现线粒体DNA(mitochondrial DNA,mtDNA) ND1 (NaDH Dehydrogenase subunitⅠ)基因上3316位点存在G→A的点突变,导致丙氨酸错义突变成苏氨酸,而在80例正常对照个体中均不存在此位点突变。国内外已证实的和1.5%NIDDM发生有关的mtDNA tRNA Leu^(UUR)|基因上3243位点A→G的突变在本实验中并未发现。由此推断,3316位点G→A的突变可能与NIDDM的发生在关,3243位点A→G的突变率确实很低,可见糖尿病的发生在线粒体遗传上具有广泛的异质性。 Abstract:Using PCR-SSCP,PCR-RFLP and PCR product direct sequencing techniques,we analysed the mitochondrial DNAs(mtDNAs)of 90 patients with NIDDM (Non Insulin-Dependent Diabetes Mellitus)and those of 80 normal controls.The results showed that a G to A mutation which leads alanine’s missence mutaton to threonine in the mitochondrial ND1(NaDH Dehydrogenase subunit I) gene at nucleotide pair 3316 occurred in the blood cells of 2 patients.We have not however,indentified with the A to G mutation at nucleotide pair 3243 of the mitochondrial tRNA Leu(UUR) gene,which has been reported to associate with NIDDM in about 1.5% of the diabetic population.We infer that the mutation at position 3316 is perhaps associated with the development of NIDDM,the occurance of the mutation at position 3243 is actually rare,and NIDDM has an intensive mitochondrial genetic heterogenous background.     

人癌细胞线粒体DNA控制区序列特征分析

为了探讨癌细胞mtDNA控制区序列的变化特征, 采用PCR产物限制性片段长度多态性(PCR-RFLP)分析与直接测序相结合的方法,对比分析6株人癌细胞系、 6例癌患者及4例健康成人白细胞mtDNA控制区序列。发现第16519位T→C、16 534位A→G、46位T→G和49位A→C突变, 在癌细胞系和癌患者白细胞mtDNA中分别占50%(3/6)和33.3%(2/6), 健康成人白细胞mtDNA中未见此类型突变;第16 278位C→T突变,在癌细胞系mtDNA中占50%(3/6),显著高于正常人群mtDNA中此位点的多态性变异。表明癌细胞和癌患者白细胞mtDNA重链复制起点及其 相邻D环区的特征性突变可能与细胞癌变/或癌的易感性有关。 Abstract：　To explore the sequence feature of mitochondrial DNA(mtDNA) control region in human carcinoma cells, polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) and direct sequence techniques were used to analyze the sequence of mtDNA control region of 6 human carcinoma cell lines versus white blood cells which from 6 tumor patients and 4 normal adults. The T to C mutation at np 16 519, A to G mutation at np 16 534, T to G mutation at np 46, and A to C mutation at np 49 was found in 50% (3/6 cases) of carcinoma cell lines and in 33.3%(2/6 cases) of tumor patients, but it was not found in normal adults. The C to T mutation at np 16 278 was found in 50%(3/6 cases) of carcinoma cell lines, it was significantly higher than that of the polymorphism of normal population. These findings suggest that the typical mutation in the starting area of heavy-strand replication and the first half of D-loop region might probably be associated with carcinogenesis or susceptibility of carcinoma.     

人癌细胞线粒体DNA控制区序列特征分析

为了探讨癌细胞mtDNA控制区序列的变化特征, 采用PCR产物限制性片段长度多态性(PCR-RFLP)分析与直接测序相结合的方法,对比分析6株人癌细胞系、 6例癌患者及4例健康成人白细胞mtDNA控制区序列。发现第16519位T→C、16 534位A→G、46位T→G和49位A→C突变, 在癌细胞系和癌患者白细胞mtDNA中分别占50%(3/6)和33.3%(2/6), 健康成人白细胞mtDNA中未见此类型突变;第16 278位C→T突变,在癌细胞系mtDNA中占50%(3/6),显著高于正常人群mtDNA中此位点的多态性变异。表明癌细胞和癌患者白细胞mtDNA重链复制起点及其 相邻D环区的特征性突变可能与细胞癌变/或癌的易感性有关。 Abstract：　To explore the sequence feature of mitochondrial DNA(mtDNA) control region in human carcinoma cells, polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) and direct sequence techniques were used to analyze the sequence of mtDNA control region of 6 human carcinoma cell lines versus white blood cells which from 6 tumor patients and 4 normal adults. The T to C mutation at np 16 519, A to G mutation at np 16 534, T to G mutation at np 46, and A to C mutation at np 49 was found in 50% (3/6 cases) of carcinoma cell lines and in 33.3%(2/6 cases) of tumor patients, but it was not found in normal adults. The C to T mutation at np 16 278 was found in 50%(3/6 cases) of carcinoma cell lines, it was significantly higher than that of the polymorphism of normal population. These findings suggest that the typical mutation in the starting area of heavy-strand replication and the first half of D-loop region might probably be associated with carcinogenesis or susceptibility of carcinoma.     

Cloning, mapping and mutation analysis of human gene GJB5 encoding gap junction protein β-5

By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein β-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DNA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Charcot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two missense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion.     

Cloning, mapping and mutation analysis of human gene GJB5 encoding gap junction protein β-5

By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein p-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DMA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Char-cot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two mis-sense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR anal     

三例氨基糖甙类抗生素致聋患者的线粒体DNA测序分析

应用PCR扩增产物直接对3名氨基糖甙类抗生素致聋患者的线粒体DNA进行序 列分析, 结果表明,他们的线粒体DNA均存在第1555位核苷酸A-G的突变。因此认为该突 变是人体对氨基糖甙类抗生素致聋遗传易感性的分子基础,与氨基糖甙类抗生素共同作用造成耳聋。 Abstract:The mitochondria DNAs(mtDNAs)of three patients with AAID were analysed using the method of direct sequencing of their PCR products.The results showed that all their mtDNAs had an A-G mutation at nucleotides 1555.It is considered that this mutation is the molecular basis causing human susceptibility to Aminoglycoside Antibiotics toxicity which in cooperation with Aminoglycoside Antibiotics results in deafness.     

Arsenic trioxide promotes mitochondrial DNA mutation and cell apoptosis in primary APL cells and NB4 cell lines

This study aimed to investigate the effects of arsenic trioxide(As2O3) on the mitochondrial DNA(mtDNA) of acute promyelocytic leukemia(APL) cells.The NB4 cell line was treated with 2.0 μmol/L As2O3 in vitro,and the primary APL cells were treated with 2.0 μmol/L As2O3 in vitro and 0.16 mg kg-1 d-1 As2O3 in vivo.The mitochondrial DNA of all the cells above was amplified by PCR,directly sequenced and analyzed by Sequence Navigatore and Factura software.The apoptosis rates were assayed by flow cytometry.Mitochondrial DNA mutation in the D-loop region was found in NB4 and APL cells before As2O3 use,but the mutation spots were remarkably increased after As2O3 treatment,which was positively correlated to the rates of cellular apoptosis,the correlation coefficient:rNB4-As2O3=0.973818,and rAPL-As2O3=0.934703.The mutation types include transition,transversion,codon insertion or deletion,and the mutation spots in all samples were not constant and regular.It is revealed that As2O3 aggravates mtDNA mutation in the D-loop region of acute promyelocytic leukemia cells both in vitro and in vivo.Mitochondrial DNA might be one of the targets of As2O3 in APL treatment.     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.