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81.
基于Linux的cDNA文库序列分析平台的构建与应用 总被引:1,自引:0,他引:1
本研究构建了基于Linux的cDNA文库序列分析平台,该分析平台可大批量自动处理测序后的序列,包括载体序列的去除、序列格式的转换、序列的自动拼接、序列对数据库的相似性搜索及全长ORF的预测等,可加速对大规模测序数据的分析和利用。用该平台对构建的野生大豆盐胁迫全长cDNA文库部分测序结果进行分析和利用。用该平台对构建的野生大豆盐胁迫全长cDNA文库部分测序结果进行分析,获得了较好的结果,已得到多个具有潜在价值的新基因序列。 相似文献
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Ma Z Liu T Li X Zhou T Xiao L Que H Tian D Jing S Liu S 《Cellular and molecular neurobiology》2006,26(3):277-288
Spinal cord injury (SCI) initiates a cascade of events and these responses to injury are likely to be mediated and reflected by changes in mRNA concentrations. As a step towards understanding the complex mechanisms underlying repair and regeneration after SCI, the gene expression pattern was examined 4.5 days after complete transection at T8-9 level of rat spinal cord. Improved subtractive hybridization was used to establish a subtracted cDNA library using cDNAs from normal rat spinal cord as driver and cDNAs from injured spinal cord as tester. By expressed sequence tag (EST) sequencing, we obtained 73 EST fragments from this library, representing 40 differentially expressed genes. Among them, 32 were known genes and 8 were novel genes. Functions of all annotated genes were scattered in almost every important field of cell life such as DNA repair, detoxification, mRNA quality control, cell cycle control, and signaling, which reflected the complexity of SCI and regeneration. Then we verified subtraction results with semiquantitative RT-PCR for eight genes. These analyses confirmed, to a large extent, that the subtraction results accurately reflected the molecular changes occurring at 4.5 days post-SCI. The current study identified a number of genes that may shed new light on SCI-related inflammation, neuroprotection, neurite-outgrowth, synaptogenesis, and astrogliosis. In conclusion, the identification of molecular changes using improved subtractive hybridization may lead to a better understanding of molecular mechanisms responsible for repair and regeneration after SCI. 相似文献
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Hans Peter Comes Joachim W. Kadereit Andreas Pohl Richard J. Abbott 《Plant Systematics and Evolution》1997,206(1-4):375-392
Chloroplast DNA (cpDNA) and isozyme variation were analyzed over a range of populations of two infraspecific taxa of the tetraploidSenecio vulgaris. The isozyme data were supportive of the hypothesis that the weedy and cosmopolitanS. vulgaris var.vulgaris is an evolutionary derivative ofS. vulgaris subsp.denticulatus from the coasts of W Europe and montane altitudes in S Spain and Sicily. The two taxa exhibited a very high genetic identity with subsp.denticulatus containing slightly more isozyme diversity than was found in var.vulgaris. — Three cpDNA haplotypes (A, B, C) already known from other Mediterranean diploid species ofSenecio were resolved in var.vulgaris, and an additional fourth haplotype (E) was found in subsp.denticulatus. Two alternative hypotheses were chosen to account for the origin and maintenance of the observed cpDNA composition ofS. vulgaris. It either reflects (1) the retention of an ancestral polymorphism which stems from the recurrent and polytopic formation of ancestral tetraploid lineages; or (2)S. vulgaris originally was characterized by haplotype E, and haplotypes A, B and C were acquired through repeated introgressive hybridization with related diploid species. The finding that very low levels of nuclear (isozyme) diversity were present in both taxa ofS. vulgaris examined supports the second of these two hypotheses; however, more detailed analysis of nuclear genetic diversity is required before a firm conclusion can be reached on this matter.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday 相似文献
87.
野生纤毛虫同工酶微量等电聚焦分析探索 总被引:2,自引:1,他引:2
微量电泳是用来分离和表征提取于少量生物材料中的核酸和蛋白质的分析技术。作者以缘毛目螅状独缩虫(Carchesium polypinum Linne,1758)为材料,用微量等电聚焦(Microisoelectric focussing)探索了分析野生纤毛虫同工酶的可行性。实验结果表明:(1) 样品量小至两个群体螅状独缩虫(约200个个体)即可进行酯酶同工酶微量等电聚焦分析;(2) 自野外采集材料中立即分离制备的螅状独缩虫匀浆上清液的酯酶同工酶酶谱与实验室内放置10h后分离制备的酶谱几乎一致。因此,野生纤毛虫同工酶可用微量等电聚焦进行分析。 相似文献
88.
Isozyme Diversity is Low in Paeonia californica (Paeoniaceae) 总被引:1,自引:0,他引:1
Abstract The California Peony ( Paeonia californica ), a regional endemic and outcrossing species, is almost completely monomorphic for 23 isozyme loci. The level of genetic diversity in the California Peony is similar to that of narrow endemics and/or self-fertilizing species. This paradoxical result may be explained by either of two hypotheses: 1) low initial polymorphism of the ancestral genome, or 2) population bottle neck. 相似文献
89.
Li Yang LingLing Wang JunPing Peng Lu Yu Tao Liu WenChuan Leng Jian Yang LiHong Chen WenLiang Zhang Qian Zhang YiPeng Qi Qi Jin 《中国科学:生命科学英文版》2007,50(3):377-384
Trichophyton rubrum is a dominating superficial dermatophyte, whose conidial germination is correlated to pathopoiesis and a highly important
developmental process. To investigate the changes of physiology, biochemistry and cytology during the germination, we selected
3364 function identified ESTs from T. rubrum cDNA library to construct cDNA microarrays, and compared the gene expression levels of conidia and germinating phase. Data
analysis indicated that 335 genes were up-regulated during the germination, which mainly encoded translated, modified proteins
and structural proteins. The constituents of cell wall and cell membrane were synthetized abundantly, suggesting that they
are the foundation of cell morphogenesis. The ingredients of the two-component signal transduction system were up-regulated,
presuming that they were important for the conidial germination. Genes of various metabolic pathways were expressed prosperously,
especially the genes that participated in glycolysis and oxidative phosphorylation were up-regulated on the whole, demonstrating
that in the environment with sufficient oxygen and glucose, conidia obtained energy through aerobic respiration. This paper
provides important clues which are helpful to understanding the changes in gene expression, signal conduction and metabolism
characteristics during T. rubrum conidial germination, and possess significant meaning to the study of other superficial dermatophytes.
Supported by the National High Technology Research and Development Program of China (Grant No. 2001AA223021) and National
Key Technologies R&D Programme (Grant No. 2002BA711A14) 相似文献
90.
人致肺纤维化相关因子的克隆和生物信息学分析 总被引:1,自引:0,他引:1
几丁质酶是自然界广泛存在的一类降解几丁质的水解酶类,但是直至近些年才在哺乳动物体内发现存在有几丁质酶样蛋白.早年曾于矽肺大鼠中纯化出矽诱导的支气管肺泡灌洗蛋白iSBLP58,体外具有促进人胚肺成纤维细胞2BS增殖的作用,N端测序显示与哺乳动物几丁质酶蛋白家族成员具有高度同源性.生物信息学分析表明,来源于人的结肠、肾和胃的几个表达序列标签(EST)克隆和大鼠的这一蛋白质序列匹配.随后成功地从人肾RNA样品中克隆到一组cDNA,其序列及相应的氨基酸序列彼此高度相似,并与GenBank中的几个人几丁质酶蛋白高度相似.和人基因组序列比较,揭示这些分子可能来自于同一基因,为可变剪切的产物. 相似文献