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Expression of betaine aldehyde dehydrogenase gene and salinity tolerance in rice transgenic plants 总被引:9,自引:0,他引:9
Betaine as one of osmolytes plays an important role in osmoregulation of most high plants. Betaine aldehyde dehydrogenase C BADH) is the second enzyme involved in betaine biosynthesis. The BADH gene from a halophite, Atriplex hortensis, was transformed into rice cultivars by bombarment method. Totally 192 transgenic rice plants were obtained and most of them had higher salt tolerance than controls. Among transgenic plants transplanted in the saline pool containing 0.5% NaCl in a greenhouse, 22 survived, 13 of which set seeds, and the frequency of seed setting was very low, only 10% . But the controls could not grow under the same condition. The results of BADH ac-tivity assay and Northern blot showed that the BADH gene was integrated into chromosomes of transgenic plants and expressed. 相似文献
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山西省草兔的一些生态资料 总被引:4,自引:0,他引:4
山西省草兔的一些生态资料卢欣,申守义,高尚文(山西省生物研究所太原030006)关键词草兔,粪便样方,益害分析,天敌和寄生虫草兔(Lepuscapensis)是我国最重要的小型狩猎动物之一,但其生态仅有零星报道[1,2]。1987-1992年,我们在... 相似文献
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以甜菜坏死黄脉病毒(BNYVV)内蒙分离物的总RNA为模板,通过反转录-PCR扩增获得BNYVVRNA3全长cDNA。将其克隆到pGEM-7Zf(+)上,得到重组质粒pGBY56。序列分析结果表明,内蒙分离物RNA3基因组全长为1775nt,其中包含3个开放阅读框架,分别编码25kD蛋白、4.6kD蛋白和一种由59个氨基酸组成的N蛋白。与法国F2分离物、德国G1分离物和日本S分离物相比,其核苷酸序列的同源性分别为96.4%、96.8%和97.3%。将25kD蛋白编码基因克隆到pJW2上,构建了该基因的原核表达载体。SDS-PAGE和Westernbloting分析结果表明,25kD蛋白基因在E.coliBL21(DE3)中经温度(42℃)诱导后,可特异地表达25kD蛋白 相似文献
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Telomereistheessentialgeneticlocusattheendsofalleukaryoticchromosomes.TheywereproposedtocapchromosomespreventingtheendtoendfusionsbetweenbrokenendsandcontinualterminalDNAlossduringreplication.Theyalsohaveinfluencesonmembranechromosomeinteractionandthe… 相似文献
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Vibrio cholerae is commonly found in estuarine water systems. Toxigenic O1 and O139 V. cholerae strains have caused cholera epidemics and pandemics, whereas the nontoxigenic strains within these serogroups only occasionally lead to disease. To understand the differences in the genome and clonality between the toxigenic and nontoxigenic strains of V. cholerae serogroups O1 and O139, we employed a whole genome PCR scanning (WGPScanning) method, an rrn operon-mediated fragment rearrangement analysis and comparative genomic hybridization (CGH) to analyze the genome structure of different strains. WGPScanning in conjunction with CGH revealed that the genomic contents of the toxigenic strains were conservative, except for a few indels located mainly in mobile elements. Minor nucleotide variation in orthologous genes appeared to be the major difference between the toxigenic strains. rrn operon-mediated rearrangements were infrequent in El Tor toxigenic strains tested using I-CeuI digested pulsed-field gel electrophoresis (PFGE) analysis and PCR analysis based on flanking sequence of rrn operons. Using these methods, we found that the genomic structures of toxigenic El Tor and O139 strains were syntenic. The nontoxigenic strains exhibited more extensive sequence variations, but toxin coregulated pilus positive (TCP+) strains had a similar structure. TCP+ nontoxigenic strains could be subdivided into multiple lineages according to the TCP type, suggesting the existence of complex intermediates in the evolution of toxigenic strains. The data indicate that toxigenic O1 El Tor and O139 strains were derived from a single lineage of intermediates from complex clones in the environment. The nontoxigenic strains with non-El Tor type TCP may yet evolve into new epidemic clones after attaining toxigenic attributes. 相似文献
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A naturally cholera toxin gene negative Vibrio cholerae (O1, E1 Tor, Ogawa) strain, named IEM101, was isolated in China. The human volunteer tests showed that this strain was safe,
able to colonize the intestinal mucosa, and able to induce a strong immune response. Also other studies indicated that it
was an efficient live vector to deliver heterologous antigens. In this article, a thymidylate synthase gene (thyA)-defined mutant was constructed using homologous recombination. Except for the morphological changes in minimal medium and
slightly reduced colonization capacity, mutant strain IEM101-T maintained most of the desirable features as the wild-type
strain IEM101 in terms of growth rate and immunogenicity. However, the mutant was more biosafe than its parent strain. In
conclusion, IEM101-T may be a promising strain to develop live vaccine candidate of cholera or an attractive vaccine vector
to deliver heterologous antigens in vivo. 相似文献
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Jun Liu Da Ha Zongming Xie Chunmei Wang Huiwen Wang Wanke Zhang Jinsong Zhang Shouyi Chen 《遗传学报》2008,35(7):441-449
Plant morphology is specified by leaves and flowers, and the shoot apical meristem (SAM) defines the architecture of plant leaves and flowers. Here, we reported the characterization of a soybean KNOX gene GmKNT1, which was highly homologous to Arabidopsis STM. The GmKNT1 was strongly expressed in roots, flowers and developing seeds. Its expression could be induced by IAA, ABA and JA, but inhibited by GA or cytokinin. Staining of the transgenic plants overexpressing GmKNT1-GUS fusion protein revealed that the GmKNT1 was mainly expressed at lobe region, SAM of young leaves, sepal and carpel, not in seed and mature leaves. Scanning electron micros- copy (SEM) disclosed multiple changes in morphology of the epidermal cells and stigma. The transgenic Arabidopsis plants overexpress- ing the GmKNT1 showed small and lobed leaves, shortened internodes and small clustered inflorescence. The lobed leaves might result from the function of the meristems located at the boundary of the leaf. Compared with wild type plants, transgenic plants had higher ex- pression of the SAM-related genes including the CUP, WUS, CUC1, KNAT2 and KNAT6. These results indicated that the GmKNT1 could affect multiple aspects of plant growth and development by regulation of downstream genes expression. 相似文献