利用RAPD分子标记定位2个水稻稻瘟病菌非致病性基因

选择日本鉴别品种新 2号和K5 9,对源于云南省的水稻稻瘟病菌可育性菌株CHL12 4(MAT1 1)和CHL12 5 (MAT1 2 )及其杂交后代 72个子囊菌株的非致病性 (无毒性 )进行了遗传分析。结果表明 ,菌株CHL12 4对新 2号 (含有效抗性基因Pish)和K5 9(Pit)的非致病性分别由非致病性基因Avr2 Pish和Avr2 Pit控制。通过对这 2个基因控制的非致病性反应进行列联卡方测验 ,显示这 2个基因连锁在一起 ,重组率为 2 6 .8%。进一步利用分离群体分析法 ,对这 2个基因进行了RAPD (随机扩增多态性DNA)分析。结果发现 ,2个RAPD标记OPW 0 6 64 5和OPW 1364 5与非致病性基因Avr2 Pish连锁 ,它们的重组率分别为 2 7.8%和 2 6 .5 %;另 1个RAPD标记OPR11517则与非致病性基因Avr2 Pit连锁 ,重组率为 2 3.5 %。

病原细菌致病性基因表达的环境调控

病原细菌致病性基因表达的环境调控胡稳奇（湖南省生物研究所长沙４４０００６）细菌是动物、植物乃至人类的重要致病微生物，可以引起人类的许多烈性和急性传染病，如鼠疫、霍乱、伤寒和传染性痢疾等。病理学家很久以前就注意到，病原细菌引起致病，是病原、行主及环境条...

幽门螺杆菌基因组可塑性区中新的致病性基因

幽门螺杆菌(Hp)为革兰阴性、螺旋形的微需氧杆菌，它在慢性胃炎、消化性溃疡、胃肿瘤的致病中发挥重要作用，但不同菌株的致病性不尽相同。细胞毒素相关基因(cagA)是第1个被发现的存在于致病岛(cagA PAI)的毒性基因；而存于cag PAI外，但与cag PAI特点相似的基因区。

成骨不全COL1A1基因无义突变一例报告

成骨不全症是一种遗传性疾病,主要特征为骨量低、骨脆性增加以及损害其他系统表现出骨折、骨骼畸形、身材矮小、蓝巩膜、牙本质发育不全等。本文报告1例成骨不全症患者的病史;对其外周血基因采用全序列外显子基因工程检测信息技术,检测相关致病基因,结果在患者COL1A1基因17号染色体(Chr17:50191826)编码区发现杂合变异:NM_000088.4:exon31:c.2089C>T(p.Arg697^(*))。

沙门氏菌跨物种感染基因的挖掘及鉴定

沙门氏菌,肠杆菌科是导致人兽共患病的重要病原体。微生物的跨物种感染是全世界研究的热点。本实验选用从鸡蛋和病人中分离的30种肠炎沙门氏菌菌株进行全基因组测序,使用Ridom SeqspHere+进行cgMLST分析,挖掘可能的人兽共患性致病基因,分别为invA、pduD、kduI、yigM、mgtA,并以这些靶基因为模板,设计PCR引物,建立五重PCR鉴定沙门氏菌致病基因的方法。以包含上述5个基因的G1菌株作为阳性检测菌株,并对建立的五重PCR进行检测,结果显示均扩增出目的条带且无杂带,说明建立的五重PCR检测方法较为成功。该检测方法能够同时鉴定沙门氏菌产生的多种毒力基因,具有特异性强、灵敏度高的特点,为沙门氏菌菌株的检测和鉴定提供了一种新的方法。

儿童G6PD缺乏症355例临床分析

目的探讨儿童G6PD缺乏症的发病因素、临床特点、诊断及治疗措施，为指导临床治疗提供依据。方法回顾性总结355例儿童G6PD缺乏症的临床资料，对其诱因、发病机制、临床表现、实验室检查、治疗及预后进行分析。结果G6PD缺乏症发病高峰年龄为1～3岁，男：女=17．7：1，春季多发；蚕豆、药物、感染等因素均为发病诱因，其中蚕豆所致的发病率最高，占78．3％；贫血、黄疸、尿色改变、肝肿大为主要临床表现；多伴有血常规、尿常规、胆红素、CK-MB、G6PD酶活性、高铁血红蛋白还原试验、血清结合珠蛋白等结果的异常；本病有3种最常见致病性基因突变，基因型及携带者比例分别为G1388A38．6％、G1376T31．2％、A95G10．8％；全部患儿经去除诱因、输血、碱化尿液等对症支持治疗后可治愈出院，该病预后可，具一定的自限性。结论蚕豆病是G6PD缺乏症最常见的临床表现形式；G1388A、G1376T、A95G是我国G6PD缺乏症最常见的三种致病性基因突变类型，各致病性基因突变之间没有明显的临床表现及实验室检查差异。

Fluorescent co-localization of PTS1 and PTS2 and its application in analysis of the gene function and the peroxisomal dynamic in Magnaporthe oryzae

The peroxisomal matrix proteins involved in many important biological metabolism pathways in eukaryotic cells are encoded by nucleal genes, synthesized in the cytoplasm and then transported into the organelles. Targeting and import of these proteins depend on their two peroxisomal targeting signals （PTS 1 and PTS2） in sequence as we have known so far. The vectors of the fluorescent fusions with PTS, i.e., green fluorescence protein （GFP）-PTS1, GFP-PTS2 and red fluorescence protein （RFP）-PTS1, were constructed and introduced into Magnaporthe oryzae Guy ll cells. Transformants containing these fusions emitted fluorescence in a punctate pattern, and the locations of the red and green fluorescence overlapped exactly in RFP-PTS 1 and GFP-PTS2 co-transformed strains. These data indicated that both PTS1 and PTS2 fusions were imported into peroxisomes. A probable higher efficiency of PTS1 machinery was revealed by comparing the fluorescence backgrotmds in GFP-PTS1 and GFP-PTS2 transformants. By introducing both RFP-PTS1 and GFP-PTS2 into Amgpex6 mutants, the involvement of MGPEX6 gene in both PTS1 and PTS2 pathways was proved. In addition, using these transformants, the inducement ofperoxisomes and the dynamic of peroxisomal number during the pre-penetration processes were investigated as well. In summary, by the localization and co-localization of PTS1 and PTS2, we provided a useful tool to evaluate the biological roles of the peroxisomes and the related genes.

Hepatitis C virus genotypes in Serbia and Montenegro: The prevalence and clinical signifi cance

AIM： To investigate the prevalence of hepatitis C virus （HCV） genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection. METHODS： A total of 164 patients was investigated. Complete history, route of infection, assessment of alcohol consumption, an abdominal ultrasound, standard biochemical tests and liver biopsy were done. Gene sequencing of 5＇ NTR type-specific PCR or commercial kits was performed for HCV genotyping and subtyping. The SPSS for Windows （version 10.0） was used for univariate regression analysis with further multivariate analysis. RESULTS： The genotypes 1, 2, 3, 4, 1b3a and 1b4 were present in 57.9%, 3.7%, 23.2%, 6.7%, 6.7% and 1.8% of the patients, respectively. The genotype 1 （mainly the subtype 1b） was found to be independent of age in subjects older than 40 years, high viral load, more severe necro-inflammatory activity, advanced stage of fibrosis, and absence of intravenous drug abuse. The genotype 3a was associated with intravenous drug abuse and the age below 40. Multivariate analysis demonstrated age over 40 and intravenous drug abuse as the positive predictive factors for the genotypes lb and 3a, respectively.CONCLUSION： In Serbia and Montenegro, the genotypes 1b and 3a predominate in patients with chronic HCV infection. The subtype lb is characteristic of older patients, while the genotype 3a is common in drug abusers. Association of the subtype lb with advanced liver disease, higher viral load and histological activity suggests earlier infection with this genotype and eventually its increased pathogenicity.

CHARACTERIZATION OF PATHOGENIC FUNGI GENOMES USING PULSED FIELD GEL ELECTROPHORESIS

Pulsed field gel electrophoresis(PFGE) has been firstly introduced in characterization of the pathogenic fungi Penicillium marne f fei and Exophiala dermatitidis genomes.The numbers and sizes of their chromosomes have been detected.Polymorphism was identified on the smallest chromosome of E.dermatitidis.The result shows that PFGE for characterization of large molecular DNA pathogenic fungi is very suitable,it is more simple and more efficacy.The result also shows the diversity of pathogenic fungi is relative common even in rare occurred pathogenic fungi such as E.dermatitidis.

Kimchi and soybean pastes are risk factors of gastric cancer

AIM: This case-control study investigated the effects of kimchi,soybean paste, fresh vegetables,nonfermented alliums, nonfermented seafood, nonfermented soybean foods, and the genetic polymorphisms of some metabolic enzymes on the risk of gastric cancer in Koreans. METHODS: We studied 421 gastric cancer patients and 632 age- and sex-matched controls. Subjects completed a structured questionnaire regarding their food intake pattern. Polymorphisms of cytochrome P450 1A1 (CYP1A1), cytochrome P450 2E1 (CYP2E1), glutathione S-transferase mu 1 (GSTM1),glutathione S-transferase theta 1 (65777) and aldehyde dehydrogenase 2 (ALDH2) were investigated. RESULTS: A decreased risk of gastric cancer was noted among people with high consumption of nonfermented alliums and nonfermented seafood. On the other hand, consumption of kimchi, and soybean pastes was associated with increased risk of gastric cancer. Individuals with the CYP1A1 Ile/Val or Val/Val genotype showed a significantly increased risk for gastric cancer. Increased intake of kimchi or soybean pastes was a significant risk factor for the CYP1A1 lie/lie, the CYP2E1 c1/c1,the GSTM1 non-null, the GSTT1 non-null, or the ALDH2 *1/*1 genotype.In addition, eating soybean pastes was associated with the increased risk of gastric cancer in individuals with the GSTM1 null type. Nonfermented alliums were significant in individuals with the CYP1A1 lie/lie, the CYP2E1 c1/c2 or c2/c2, the GSTT1 null, the GSTT1 non-null, or the ALDH2 *1/*2 or *2/*2 genotype,nonfermented seafood was those with the CYP1A1 lie/lie,the CYP2E1 c1/c1, the ALDH2 *1/*1 genotype or any type of GSTM1 or GSTT1. In homogeneity tests, the odds ratios of eating kimchi for gastric cancer according to the GSTM1 or 65777 genotype were not homogeneous. CONCLUSION: Kimchi, soybean pastes, and the CYP1A1 Ile/Val or Val/Val are risk factors,and nonfermented seafood and alliums are protective factors against gastric cancer in Koreans. Salt or some chemicals contained in kimchi and soybean pastes, which are increased by fermentation,would play important roles in the carcinogenesis of stomach cancer.Polymorphisms of the CYP1A1, CYP2E1, GSTM1, GSTT1, and ALDH2 genes could modify the effects of some environmental factors on the risk of gastric cancer.

Functional genomics in the rice blast fungus to unravel the fungal pathogenicity

A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae is an economically important plant pathogenic fungus whose genome is fully sequenced. Recently we have reported the development and application of functional genomics platform technologies in M. oryzae. This model approach would have many practical ramifications in design and implementation of upcoming functional genomics studies of filamentous fungi aimed at understanding fungal pathogenicity.

Wheat Stripe Rust Virulence and Varietal Resistance in the Foot Hill Himalayas of Nepal

Stripe rust, caused by Puccinia striiformis f. sp. tritici （Pst） is an important disease of wheat （Triticum aestivum） in Nepal, which is a part of the Himalayas stretching over the North of Nepal, India, Pakistan, Bhutan and beyond. Wheat production plays a crucial role in food security of the marginal hill farmers of Nepal. Frequent epidemics of the rust have caused huge loss in farmer＇s field. Periodic monitoring during 1980-2008 showed that changes in virulence occurred during this period. The objective of this study was to evaluate Pst resistance and its effective genes in wheat genotypes. For this, trap nurseries, wheat stripe rust differentials, commercial cultivars and advanced breeding lines were tested under artificial epiphytotic and natural hot spots conditions during 2005 to 2010. Four genes （Yr5, Yr10, Yr15 and YrSp） consistently showed resistance to the prevailing races. The gene Yr9 and Yr27 in combinations with Yrl8 were found effective. Other lines with combination of minor genes were also found effective. The genotypes Amadina, Kukuna, Tukuru, Kakatsi and Buck Buck widely used in breeding program were resistant. The cultivation of varieties WK1204, Gautam, Gaura and Dhaulagiri have ensured genetic diversity for the rust resistance and slowed down frequent occurrence of epidemics. The findings of these studies could help in developing effective varietal resistance program in the sub-continent.

Construction of two selectable markers for integrative/conjugative plasmids in Flavobacterium columnare

Flavobacterium columnare, the etiological agent of colunmaris disease, is one of the most important and widespread bacterial pathogens of freshwater fish. In this study, we constructed two artificial selectable markers （chloramphenicol and spectinomycin resistance） for gene transfer in F. columnare. These two new artificial selectable markers, which were created by placing the chloramphenicol or spectinomycin resistance gene under the control of the native acs regulatory region of F. columnare, were functional in both F. columnare and Escherichia coli. The integrative/conjugative plasmids constructed by using these markers were introduced into F. columnare G4 via electroporation or conjugation. The integrated plasmid DNA was confirmed by Southern blotting and PCR analysis. These two markers can be employed in future investigations into gene deletion and the pathogenicity of virulence factors in F. columnare.

贵州省1起人间疑似炭疽疫情的病原学诊断与分析

目的从病原学角度判定1起人间疑似炭疽疫情,为疫情的处置提供科学依据。方法采用革兰氏染色、串珠试验、噬菌体实验、生化试验对病人水疱液标本和采集的土壤标本进行炭疽芽孢杆菌培养分离和鉴定,应用Real-time PCR检测致病性基因PA和capA。结果从土壤标本中分离到1株疑似炭疽芽孢杆菌,细菌学方法鉴定为炭疽芽孢杆菌,Real-time PCR检测致病性基因PA和capA均为阳性。结论该起疫情为炭疽芽孢杆菌引起,患者感染为接触炭疽杆菌污染的土壤所致。

Alteration of encephalomyocarditis virus pathogenicity due to a mutation at position 100 of VP1

Encephalomyocarditis virus (EMCV) infection leads to many diseases including encephalitis,myocarditis and diabetes in its natural host,the mouse.In this study,we generated four cDNA clones with a point mutation at position 100 of VP1.The amino acids isoleucine,alanine,serine and proline were substituted with threonine in the four different clones of EMCV strain BJC3 by site-specific mutagenesis,and viable viruses were rescued.Although all mutants and wild-type viruses display different plaque morphologies,they replicate comparably in BHK-21 cells.The pathogenicity of the mutated viruses was systematically analyzed to investigate the importance of this amino acid in the viral pathogenicity and disease phenotype of EMCV infection in mice.The results showed that the isoleucine(T1100I) and proline-mutated viruses (T1100P) exhibited a reduced mortality,lower cerebral virus loads and alleviated brain damage while the viruses with serine (T1100S) and alanine (T1100A) substitutions displayed similar properties as the wild-type virus.These findings indicate that the amino acid at position 100 of VP1 is important for EMCV in vivo infection,and its mutation alters the pathogenicity of viral infection in mice.

Pathogenicity of an FAdV-4 isolate to chickens and its genomic analysis

Fowl adenovirus serotype 4(FAdV-4)strain SD1511 was isolated from chickens with severe inclusion body hepatitis and hydropericardium syndrome in Shandong Province,China.The isolate was cultured in primary chicken embryo kidney cells.A study of pathogenicity indicated that SD1511 readily infected 7–35-d-old chickens by intramuscular injection and intranasal and oral routes,causing 50%–100%mortality.The 35-d-old chickens suffered more severe infection than 7-and 21-d-old chickens with mortality highest in the intramuscular injection group.The serum from surviving chickens showed potent viral neutralizing capability.The complete genome of SD1511 was sequenced and analyzed.The strain was found to belong to the FAdV-4 cluster with more than 99%identity with the virulent FAdV-4 strains isolated in China in recent years except for some distinct variations,including deletions of open reading frame 27(ORF27),ORF48,and part of ORF19.Our findings suggest that SD1511 might be used as a prototype strain for the study of pathogenesis and vaccine development.

Mutations in CCIN cause teratozoospermia and male infertility

Teratozoospermia is usually associated with defective spermiogenesis and is a disorder with considerable genetic heterogeneity. Although previous studies have identified several teratozoospermia-associated genes, the etiology remains unknown for a majority of affected men. Here, we identified a homozygous missense mutation and a compound heterozygous mutation of CCIN in patients suffering from teratozoospermia. CCIN encodes the cytoskeletal protein Calicin that is involved in the formation and maintenance of the highly regular organization of the calyx of mammalian spermatozoa, and has been proposed to play a role in sperm head structure remodeling during the process of spermiogenesis. Our morphological and ultrastructural analyses of the spermatozoa obtained from all three men harboring deleterious CCIN mutants reveal severe head malformation. Further immunofluorescence assays unveil markedly reduced levels of Calicin in spermatozoa. These patient phenotypes are successfully recapitulated in mouse models expressing the disease-associated variants, confirming the role of Calicin in male fertility.Notably, all mutant spermatozoa from mice and human patients fail to adhere to the zona mass, which likely is the major mechanistic reason for CCIN-mutant sperm-derived infertility. Finally, the use of intracytoplasmic sperm injections(ICSI) successfully makes mutated mice and two couples with CCIN variants have healthy offspring. Taken together, our findings identify the role of Calicin in sperm head shaping and male fertility, providing important guidance for genetic counseling and assisted reproduction treatments.