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61.
To determine the level of microsatellite sequence differences and to use the information to construct a phylogenetic relationship for cultivated tetraploid cotton (Gossypium spp.) species and their putative diploid ancestors, 10 genome-derived microsatellite primer pairs were used to amplify eight species, including two tetraploid and six diploid species, in Gossypium. A total of 92 unique amplicons were resolved using polyacrylamide gel electrophoresis. Each amplicon was cloned, sequenced, and analyzed using standard phylogenetic software. Allelic diversities were caused mostly by changes in the number of simple sequence repeat (SSR) motif repeats and only a small proportion resulted from interruption of the SSR motif within the locus for the same genome. The frequency of base substitutions was 0.5%-1.0% in different genomes, with only few indels found. Based on the combined 10 SSR flanking sequence data, the homology of A-genome diploid species averaged 98.9%, even though most of the amplicons were of the same size, and the sequence homology between G. gossypioides (Ulbr.) Standl. and three other D-genome species (G. raimondii Ulbr., G. davidsonii Kell., and G. thurberi Tod.) was 98.5%, 98.6%, and 98.5%, respectively. Phylogenetic trees of the two allotetraploid species and their putative diploid progenitors showed that homoelogous sequences from the A- and D-subgenome were still present in the polyploid subgenomes and they evolved independently. Meanwhile, homoelogous sequence interaction that duplicated loci in the polyploid subgenomes became phylogenetic sisters was also found in the evolutionary history of tetraploid cotton species. The results of the present study suggest that evaluation of SSR variation at the sequence level can be effective in exploring the evolutionary relationships among Gossypuim species.  相似文献   
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Introduction HepatitisCvirus(HCV)isanRNAvirusthatcausesacuteor chronichepatitis,cirrhosis,andhepatocellularcarcinoma(HCC)[1,2].DespiterecentadvancesinthetherapyofHCV,eventhemostrecent combinationofpegylatedalpha-interferonandribavirinfailstoelimi nateinfectioninnearly50%ofthoseinfected[3,4].Nowadays,itis wellknownthatvaccineisstillthemostefficientwaystopreventvirus infection[5].Thestudyingofviralvaccinehasbeenhamperedbythe lackofanefficientcellculturesystem.Asaenvelopeglycoprotein,E2prot…  相似文献   
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INTroDUCTION.7-aminobutyric acid (GABA), a major in-hibitory neurotransmitter in vertebrate brain, in--duces neuronal inhibition via GABA receptors. Adeficiency of GABAergic inhibition has been hy-pothesized to be a principal factor in the patho-genesis of epilepsy[1]. GABA transporters are im-portant components of the GABAergic system, andfunction in part to terminate the GABA transmis-sion through rapid re-uptake of GABA into thepresynaptic neurons and surrounding gliaJ cells[2…  相似文献   
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我们对内蒙古呼盟鄂伦春族、布里亚特人、东部蒙古人血痕GLOI遗传多态性进行了研究。其中149例鄂伦春族,血样采自内蒙古呼盟鄂伦春族自治族;207例布里亚特人,血样采自鄂温克族自治旗;189名东部蒙族(陈巴尔虎、厄鲁特、巴尔虎等部族后代),血样采自海拉...  相似文献   
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郭超文GUO  Chao-wen 《遗传》2001,23(5):442-627
以骨髓细胞为材料研究赤链蛇的染色体,结果表明该物种2n=46,由8对大型的和15对微小的染色体组成,AF=50.性染色体的大小介于3号和4号之间,为ZW型;8对大型染色体均显示着丝粒C带,1-6号还显示浅染端粒C带.W染色体为整条C带阳性;该物种一对NOR位于7号染色体近着丝粒区.不同地理分布群赤链蛇核型可能经历过Z与W染色体不等交换。 Abstract:The Karyotype,C-bands and Ag-NORs of Dinodon rufozonaturn (Cantor) reported is in this paper including the diploid number(2n=46)comprising 8 pairs of macro-and 15 pairs of microchromosomes,and AF=50 in the D.rufozonatum.The sex chromosome in size locates between the autochromosones No.3 and No.4,which belongs to ZW type.The C-banding technique revealed that the all macrochromosomes there are centromerc C band,the telomeric C band was only observed in Nos.1~6,while a whole W chromosome is constitutive heterochromatinization.Two NOR were observed on the pericentric of the No.7 chromosome.  相似文献   
66.
蝗虫染色体C带带型示意图的计算机绘制   总被引:2,自引:1,他引:2  
该程序用C语言和FoxPro混合编写,把C语言的绘图优势和FoxPro强大的制表优势完美地结合起来, 通过输入实验测量的有关数据,可显示和打印出蝗虫C带带型的示意图,并可显示和打印出数据的统计表,以便于同模式图进行对照分析,并可将有关数据进行贮存。该程序稍作改动后可推广到其他动植物的C带以及其他带型示意图的绘制中。 Abstract:Using this program,we can draw all chromosomes of a species in line.Moreover,it can express centromere C-band,terminal C-band and internal C-band of each chromosome.This program not only can be used for locusts,after a little change,it can be used for all animals and plants.  相似文献   
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This study was designed to explore the RNA interference technique in inhibition of the expression of the mouse fibrinogen like protein 2(mfgl2),which has been reported to be involved in the development a variety of diseases including fulminant viral hepatitis.A plasmid named p-mfgl2shRNA,complementary to the sequence of mfgl2 was constructed,while another short hairpin RNA(shRNA) which was a mutated form of the mfgl2shRNA sequences was used as a control.A plasmid named pEGFP-mfgl2 expressing the mfgl2-EGFP fusion protein was also constructed for the screening of the effect of p-mfgl2shRNA on mfgl2 expression.By cotransfection of p-mfgl2shRNA and pEGFP-mfgl2 or pcDNA3.1-mfgl2 expression construct into CHO cells or HeLa cells,the inhibition of mfgl2 expression by mfgl2shRNA was analyzed by direct observation through fluorescent microscopy,FACS,RT-PCR and immunohistochemistry staining.The experiments showed the significant inhibitory effect of p-mfgl2shRNA on mfgl2 expression at 48h post-transfection in both CHO and Hela cell lines with the inhibitory efficiency as high as 80.1%.The study demonstrated that the construct of p-mfgl2shRNA successfully interfered with the mfgl2 expression in vitro.  相似文献   
68.
INTRODUCTIONThaillll (TNF-related apoptosis inducing ligand)is a recently described member of the TNF family.Like other members of the TNF ligand family) availcould induce apoptosis of neoplastically transformedcells by priVating cell surface death receptors ThailRI and ThaiLR212].Trail has been demonstrated to play an important role in homeostasis of immune system includ.lug eradication of the old lymphocytel3], actiVationinduced T cell deathI41, regulation Of T cen eXPansion by…  相似文献   
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