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1.
水稻细菌性条斑病和白叶枯病抗性遗传研究   总被引:7,自引:0,他引:7  
徐建龙  王汉荣 《遗传学报》1997,24(4):330-335
分析了Hashikalmi,Dular和90IRBBN44三个抗源品种对水稻细菌性条斑病S-103菌株和白叶枯病P1菌系的抗性遗传。结果表明,Hashikalmi和Dular对S-103的抗性均由2对隐性基因所控制,90IRBBN44则带有1对隐性抗性基因。经等位性测定表明,Hashikalmi和Dular的2对基因中至少有1对是等位的,但它们与90IRBBN44的1对基因均不等位。3个抗源品种对P1的抗性都受1对隐性基因控制,该基因与xa-5等位。连锁遗传分析表明,Hashikalmi和Dular对S-103的2对抗细条病基因中的1对与xa-5相连锁,而90IRBBN44的1对抗性基因与xa-5呈独立遗传。本文还就开展水稻抗细菌性条斑病育种进行了讨论。  相似文献   

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根据猪瘟病毒C株的序列,以计算机辅助设计,化学合成1对引物(PF5648/PR6604),应用RTPCR技术从感染猪血中成功地扩增了我国猪瘟病毒强毒石门株NS23基因片段,大小为957bp,位于NS3基因的中部NTPase和Helicase活性区。克隆后测序,结果表明该段基因产物具有解旋酶超家族全部七个特征性保守序列,包括共同的NTP结合基序A位点(GXGKT/S)和B位点(3hy,2x)D。序列同源性比较表明,石门株与日本的ALD和GPE-株同源性最高,与其它3株猪瘟病毒(C株、Brescia株和Alfort株)的同源性也很高,并与2株牛病毒性腹泻病毒(BVDV)(NADL株和SD1株)也有较高的同源性,尤其是由核苷酸序列推导的氨基酸序列,同源性均大于90%,是瘟病毒属基因组中最保守的区段,这与该基因产物在病毒复制及聚蛋白前体加工过程中所具有的重要功能是一致的  相似文献   

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人体一些单基因性状遗传分析   总被引:30,自引:1,他引:30  
人体一些单基因性状遗传分析葛如陵,王育秀(山东滨州医学院256603)(山东北镇中学256618)单基因性状是指受一对等位基因控制的性状。单基因性状的遗传方式可分为:常染色体显性遗传(AD)、常染色体隐性遗传(AR)和伴性遗传(SL)3大类。伴性遗传...  相似文献   

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将含有鸡传染性支气管炎病毒 S1 基因c D N A 的重组转移质粒p S X I V V I+ X3 S1 . Holte 和p S X I V V I+ X3/4 S1 . Holte 分别与粉纹夜蛾核型多角体病毒 Tn N P V S V I- G D N A( O C C- ,gal+ ) 共转染草地夜蛾( Sf9) 细胞,经空斑纯化得到重组病毒 Tn N P V( X3) S1 . Holte O C C+ 和 Tn N P V( X3/4) S1 . Holte O C C+ 。将重组毒株分别感染 Tn5 B1 细胞,并进行 S D S P A G E 与 Westernblot 检测。结果表明, Tn N P V( X3/4) S1 . Holte O C C+ 在感染的细胞中高效表达了 S1 蛋白, S D S P A G E 凝胶薄层色谱分析结果显示,感染病毒后72 h S1 蛋白的表达量占细胞内总蛋白量的35 .8 % ,而 Tn N P V( X3) S1 . Holte O C C+ 感染的细胞内检测不出 S1 蛋白。经分析认为这一差异主要来自 S1 基因翻译起始位点及其附近的周围环境。  相似文献   

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动脉平滑肌细胞(sm ooth m uscle cell,SMC)是动脉粥样硬化(atherosclerosis,AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要.利用体外培养的人主动脉SMC,观察了天然高密度脂蛋白(native high density lipoprotein,N-HDL)及氧化修饰HDL(oxidized HDL,OX-HDL)对培养人主动脉SMC cyclin D1(细胞周期蛋白D1)基因转录表达的影响.结果表明:(1)N-HDL对SMCcyclin D1基因表达无影响(P> 0.05);(2)OX-HDL使SMCcyclin D1基因表达显著增强(P<0.01),其表达量随时间(2、12、24 h)延长而增加.上述结果表明,OX-HDL的致AS作用可能与其刺激SMCcyclin D1基因表达增加有关.  相似文献   

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盐生杜氏藻甘油-3-磷酸脱氢酶的分离纯化及其特性的研究   总被引:1,自引:0,他引:1  
利用PEG分级,DEAE离子交换层析,BlueSepharose拟亲和层析,MonoQ离子交换层析等手段,分离纯化盐生杜氏藻(Dunalielasalina(Dunal)Teod.)甘油三磷酸(G3P)脱氢酶(EC1.1.1.8),得到比活为12.6U/mg的电泳纯的酶,并对此酶的生化特性进行了研究。4%~20%非变性聚丙烯酰胺梯度凝胶电泳测得全酶分子量约为270kD,SDSPAGE表明该酶只有一种分子量约为65kD的亚基,据此推测该酶应为同四聚体。酶催化磷酸二羟丙酮(DHAP)还原的最适pH值为7.5,催化G3P脱氢的最适pH值为10。该酶对4个底物还原型辅酶Ⅰ(NADH),二磷酸吡啶核苷酸(DHAP),辅酶Ⅰ(NAD),G3P的表观Km值分别为63μmol/L,272μmol/L,1.53mmol/L,6.52mmol/L。该酶在保存过程中易失活。NADH能降低酶失活的速度,而NAD则不然。低浓度NaCl对酶略有保护作用,但高浓度NaCl加快酶的失活,且浓度越高效应越明显。  相似文献   

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以鸡传染性法氏囊病病毒内蒙古毒株(IBDV-NM)dsRNA为模板,用RT-PCR法扩增其主要寄主保护抗原VP2基因的全长cDNA,克隆于pUC19的XbaI/KpnI位点,进行了全序列分析。序列比较发现IBDV-NM毒株VP2基因与已报道的其它7个IBDVCJ801bkf、Cu1、PBG98、52/70、002—73、STC及VariantE毒株之间高度同源,其核苷酸序列的同源率为91.6%~96.2%,推测的氨基酸序列的同源率为96.2%~98.6%。IBDV-NM毒株VP2高变异区的第一个亲水区氨基酸序列与CJ801bkf、Cu1、PBG98、52/70、STC、002—73比较,有一个氨基酸差异,第二个亲水区氨基酸序列与上述6个毒株完全相同。而与VariantE比较,两个亲水区内各有两个氨基酸差异。此外,IBDV-NM毒株VP2具有强毒株所特有的7肽保守区:SWSASGS。这些结果表明,IBDV-NM毒株为标准血清Ⅰ型IBDV强毒株。  相似文献   

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在已发现的四种阿尔采末病(AD)相关基因中,PS1、PS2和βApp的变异被认为与早发型AD密切相关,ApoE4的出现则是晚发型AD的危险因素。近来美国学者Tanzi等发现,编码α2巨球蛋白(α2macroglobulin,α2M)的基因A...  相似文献   

9.
给大白鼠侧脑室注射马桑内酯(Coriaria Lactone, CL)(175×10- 2m ol/L2μl)后可诱发癫痫,用NADPHd 组织化学方法观察大脑皮质及海马NOS阳性神经元的变化, 结果: 大脑皮质NOS阳性神经元数目逐渐增加, 至2h 达高峰, 与生理盐水组相比差异具有非常显著性意义(P< 001), 随着CL作用时间延长NOS反应由弱变强;海马区NOS阳性神经元2h 时才出现染色明显加深。对体外培养的大脑皮质及海马神经元用CL (25×10- 5m ol/L) 作用1/2h、1h、2h、4h 后NOS阳性神经元均未见明显增加。  相似文献   

10.
甘薯叶柄原生质体有效植株再生   总被引:4,自引:0,他引:4  
将甘薯(Ipomoeabatatas(L.)Lam.)‘元气’和‘白星’(‘WhiteStar’)的叶柄原生质体培养在含有0.05mg·L-12,4D和0.5mg·L-1KT的改良MS液体培养基中,3~4d后细胞开始分裂。培养8~9周后,将直径达1~2mm的愈伤组织转移到添加0.05~0.2mg·L-12,4D和0~0.5mg·L-1KT或添加0.5~2.0mg·L-1NAA和1.0~3.0mg·L-1BAP的MS固体增殖培养基上使其增殖。转移3~5周后,将愈伤组织再转移到MS基本培养基或转移到添加2.0~3.0mg·L-1BAP的MS培养基上。当进一步转移到MS基本培养基上后,从愈伤组织或从愈伤组织形成的不定根上再生出植株。‘元气’植株再生率高达60.0%,WhiteStar高达43.4%。  相似文献   

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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.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

20.
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.  相似文献   

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