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1.
Summary

Interspecific hybridization between thre Eucalyptus species with horticultural merit, E. macrocarpa, E. pyriformis and E. youngiana, was undertaken to investigate the likelihood of success of such crosses. All combinations produced fertile seed, with interspecific crosses as successful as intraspecific. There were no differences between male species in fertility but there were differences between female trees within a species. Discriminant analysis of each cross indicated a high degree of interspecific hybridization for hybrid 166 seedlings, with all except two seedlings clustering separately from a mixture of selfed and outcrossed seedlings of either parent, when measured for a range of leaf and stem characters at three different nodes. The success of this programme in producing both large numbers of seed and large numbers of hybrids indicated that it is possible that these species could hybridize naturally if they were growing in the same location. It also demonstrated the potential of controlled pollination, between closely related species of similar floral morphology, and seedling-based hybrid recognition as a method to produce eucalypt hybrids for further evaluation for commercial horticulture.  相似文献   

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杨坤  巩振辉  李大伟 《北方园艺》2010,(14):127-130
比较了不同方法制备的大肠杆菌感受态细胞的转化效率,并优化了质粒DNA转化感受态细胞体系。结果表明:高效法制备的感受态细胞转化效率极显著高于普通法制备感受态细胞的转化效率,其效率提高了966.1%,而高效法感受态细胞转化效率与商品化的感受态细胞转化效率差异不显著。-80℃超低温长期保存时,相比较于15%甘油,以7%DMSO为冻存保护剂保存的感受态细胞其转化效率达到1.1×107,较15%甘油冻存保护剂保存的转化效率提高了69%。温浴5 min,冰浴10 min时,其转化效率最高,达到4.95×107。应用高效法制备的感受态细胞转化不同大小质粒的效率极显著高于普通大肠杆菌感受态细胞,其转化效率较普通大肠杆菌感受态细胞的提高了550%,而转化时间缩短至普通大肠杆菌感受态细胞的12.5%,仅为15min。  相似文献   

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Chromosome karyotypes of the most commonly cultivated and medicinally used Echinacea taxa, E. angustifolia DC. var. angustifolia and E. purpurea (L.) Moench., were analyzed. The chromosomes of both taxa are medium in length, ranging from 4.12 to 5.83 μm in E. angustifolia var. angustifolia and 3.99 to 6.08 μm in E. purpurea. No abrupt length changes in the chromosomes were noted. The karyotypes of the two species are generally similar, but a distinguishable feature exists in one pair of chromosomes. The centromere of chromosome pair 10 is subterminally located in E. purpurea, but terminally located in E. angustifolia var. angustifolia, which can be readily recognized in mitotic metaphase cell plates. This finding may provide useful information for Echinacea evolutionary, genetic, and breeding studies.  相似文献   

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AIM: To clone and express mouse canstatin (m canstatin) cDNA and provide a basis for the further research on its anti-angiogenic activity and potential application for cancer therapy. METHODS: Total RNA was extracted from mouse liver tissue by Trizol Reagent, and mouse canstatin cDNA was amplified by RT- PCR, then cloned into vector pMD18-T for sequencing. pET30a(+)-m canstatin recombinant plasmid was constructed and expressed in E.coli BL21 with induction of IPTG. RESULTS: Mouse canstatin cDNA is 684 bp coding 227 amino acids. The sequences of both cDNA and amino acid share high homology with human canstatin, with cDNA identity at 89% and amino acids identity at 96% to human canstatin. In the present study, pET30a(+)-m canstatin recombinant plasmid was expressed in E.coli BL21. CONCLUSION: Mouse canstatin cDNA has been cloned for the first time. Constructed pET30a(+)-m canstatin recombinant plasmid is highly expressed in E.coli BL21.  相似文献   

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Most of the achenes produced by Rosa multibracteata Hemsl. & E. H Wilson are dormant on maturity and require pretreatment to stimulate germination. To investigate the mechanism of dormancy and to develop effective methods of improving germination, roles of the pericarp, testa, and embryo of R. multibracteata in regulating dormancy were studied by investigating the effect of different pretreatments on germination. The effects of temperature and water stress were also tested with achenes treated by warm plus cold stratification. In freshly harvested achenes, pericarps are permeable and the embryo fully developed, which eliminates the possibility of physical, morphological, or morphophysiological dormancy. Germination percentage remained low (<5%) despite softening the pericarp or even removing it fully. However, fully removing the testa improved germination significantly (39%), indicating the possible presence of germination inhibitors in the testa. Dry storage, scarification with sulphuric acid (H2SO4), and warm stratification proved ineffective by themselves but when combined with cold stratification, improved germination and shortened the cold stratification period needed to break dormancy. Dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks resulted in maximum germination (72–79%) among all the treatments. In achenes scarified with H2SO4, germination increased with an increase in the duration of cold stratification. Neither gibberellic acid (GA3) nor ‘smoke water’ (water through which smoke had been bubbled for 2 h) had any positive effect on germination even on seeds that had been mechanically scarified or stratified. Both high temperature and water stress lowered germination in achenes treated with warm plus cold stratification. Our results suggest that R. multibracteata achenes have an intermediate physiological dormancy, and that dry storage for 68 weeks followed by cold stratification for 16 or 24 weeks is the best method for propagating R. multibracteata from seed.  相似文献   

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Seeds from five lots each of Echinacea angustifolia DC, and E. pallida (Nutt.) Nutt. were germinated in a growth chamber in light (40 μmol·m(-2)· s(-1)) or darkness at 25 °C for 16 to 20 d after soaking in 1 mM ethephon or water for 10 min, or moist stratification at 4 - 6 °C for two weeks. Either light or ethephon promoted seed germination of E. angustifolia and E. pallida, in comparison with darkness in nine of ten lots. Ethephon in the dark had similar or greater germination percentages than water with light. Ethephon with light improved germination in three of ten lots compared with ethephon in the dark. The effect of cold, moist stratification in comparison with darkness varied by seed lot. Five lots of E. purpurea (L.) Moench were tested; however, no treatment differences were measured. The finding that ethethon promoted E. angustifolia and E. pallida seed germination in darkness could be useful in the cultivation of these two species. Chemical name used: 2-chloroethylphosphonic acid (ethephon).  相似文献   

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阔叶猕猴桃果实GalDH cDNA 克隆及其在大肠杆菌中的表达   总被引:2,自引:0,他引:2  
尚增振  王小华  马锋旺  梁东 《园艺学报》2009,36(12):1741-1748
 以猕猴桃属植物中果实维生素C含量最高的阔叶猕猴桃(Actinidia latifolia Merr. ) 果实为试 材, 经RT2PCR扩增获得约110 kb的L - 半乳糖脱氢酶cDNA片段。生物信息学分析表明, 该cDNA片段长为997 bp, 最大开放阅读框为960 bp, 可编码319 个氨基酸残基, 命名为A lGalDH, GenBank登录号为EU525846, 核苷酸序列及其推导的氨基酸序列与已知其它植物GalDH核苷酸、氨基酸序列间的同源性分别在76%和70%以上, 且具有醛酮还原酶的保守结构域。构建了其原核表达载体pET-A lGalDH并转化大肠杆菌BL21, 经0.1 mmol·L - 1 IPTG诱导, 获得具有较高活性的表达融合蛋白6 ×His-AlGalDH。经Ni-His亲和磁珠分离纯化, 获得单一的融合目的蛋白条带, 测定其酶活为120 pmol·min- 1 ·mg- 1。  相似文献   

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AIM: Constructing plasmid that expresses human plasminogen kringle 5 gene to analyze the gene expression in E.coli. METHODS: The gene of human plasminogen kringle 5 was inserted into plasmid PBV220 EcoRI site by gene manipulation techniques and was transformed to E.coli TGI. The gene expression was observed by SDS-PAGE. RESULTS: Expression vector PBVK5 was constructed, and human plasmingen kringle 5 gene product was obtained at 42℃ induction. CONCLUSION: Expression product of human plasminogen kringle 5 gene was soluble form of proteins, and the expression amount was 9.8% in E.coli TGI total proteins.  相似文献   

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【目的】研究克隆新疆红肉苹果[Malus sieversii f.neidzwetzkyana(Dieck)Langenf]PGIP基因并进行原核表达,探讨其抗病机制。【方法】根据Genbank中已经发表的‘金冠’苹果PGIP保守区域设计1对特异引物,以新疆红肉苹果叶片总RNA为模板,T/A克隆后进行序列测定,并对该序列进行分析。随后将该蛋白成熟肽cDNA片段连接到原核表达载体pET30a(+)中,构建融合表达质粒,转化到E.coli BL21(DE3)中进行表达。【结果】序列分析表明,新疆红肉苹果PGIP基因cDNA编码区全长993 bp,编码330个氨基酸残基,命名为MsPgip,GenBank登录号为JQ001783。MsPgip分子质量为36.6 kD,等电点为7.05,有6个潜在的N-糖基化位点,信号肽为N端24个氨基酸残基。该蛋白质还具有2个连续的24个氨基酸残基大小的LRR基序(LSQLKNLTFLDLSFNNLTGAIPSSLSQ LPNLNALHLDRN-KLTGHIPIS)。与已克隆的‘澳洲青苹’、‘金冠’、‘富士’苹果PGIP氨基酸序列同源性均高达99%。原核表达产物经SDS-PAGE分析表明,表达蛋白的分子质量与预期一致。【结论】克隆了新疆红肉苹果PGIP基因,并可在大肠杆菌中表达。  相似文献   

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AIM To investigate the diagnostic value of human papillomavirus (HPV) E6/E7 mRNA and DNA detection in cervical squamous epithelial lesion screening via retrospective analysis. METHODS The HPV E6/E7 mRNA detection, HPV E6/E7 DNA detection and p16 immunohistochemistry were performed in 206 patients undergoing ThinPrep cytology test (TCT) in Gansu Provincial Hospital of Traditional Chinese Medicine, and the results of different cytological and histological grades were observed. RESULTS The positive rates of HPV E6/E7 mRNA and DNA were increased with the progress of cervical squamous intraepithelial lesions (P<0.05) in different cytological grades and histopathological grades. The detection rate of HPV E6/E7 mRNA was lower than that of HPV E6/E7 DNA (P<0.05) in atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL). The results of immunohistochemistry showed that the positive rate of p16 was increased with the grade of cervical squamous epithelial lesions (P<0.05). HPV E6/E7 DNA+p16 for cervical squamous epithelial lesion screening had the highest sensitivity, and the specificity of HPV E6/E7 mRNA was the highest. The positive predictive value of HPV E6/E7 DNA was the highest in LSIL, while the positive predictive value of HPV E6/E7 mRNA+p16 was the highest in high-grade squamous intraepithelial lesion (HSIL). CONCLUSION HPV E6/E7 DNA+p16 has the highest sensitivity in screening for cervical squamous epithelial lesions. HPV E6/E7 mRNA more accurately reflects the activation status of HPV, especially in HSIL screening, HPV E6/E7 mRNA+p16 is more specific. The results of this research provide stronger theoretical support for clinical treatment.  相似文献   

14.
AIM: To examine the expression of human endostatin in E.coli, produce its fusion protein antibody and observe its biological activity. METHODS: Endostatin gene was amplified by polymerase chain reaction,recombined with plasmid vector pGEX-2T and induced expression with IPTG.The protein activity was tested by endothelial cell proliferation inhibitory assay.Inclusion body crudely purified was used to generate polyclonal antibody to detect its expression at mouse's liver and kidney etc. RESULTS: The protein expressed was 20kD after digestion by thrombin,it appeared the anti-angiogenesis activity and Western blotting indicated the expression of endostatin in liver and kidney of mouse. CONCLUSION: The successful expression of human endostatin and the preparation of polycolonal antibody indicated its potential application in anti-angiogenesis therapy and diagnosis tumors.  相似文献   

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枇杷属种数及Eriobotrya hookeriana汉译的商榷   总被引:2,自引:0,他引:2  
林顺权  胡又厘 《果树学报》2000,17(4):300-304
查证了有关枇杷属下种类数目的英文和日文原始文献以及20世纪30年代以来的汉语文献,通过比较分析后认为,迄今为止较可靠的证据表明:枇杷属有15个种和5个变种,除两三个种或变种之外,其余均原产我国.并把外文已记载但迄今未翻译为汉语的一个种Eriobotrya hookeriana Decne的英文材料试译为汉语.  相似文献   

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AIM: To construct E. coli expression plasmid of recombinant human NDPK-A with a 6×His tag, optimize the expression condition and identify the activity of the product. METHODS: nm23-H1 was subcloned from plasmid pBVNMH1 to pQE40 which contain 6×His purification tag. The expression condition was modulated in grades to get the optimal expression. We purified protein with the Ni+-NTA affinity chromatography column, identified the immunogenicity of the product with Western blot, and measured the kinases activity with HPLC. In addition, angiogenesis inhibition activity of rhNDPK was identified by CAM. RESULTS: The sequence of nm23-H1 subclone in pQE40 was exactly correct. The expression rate of rhNDPK-A was 49.6%. Purified rhNDPK-A specially recognized the antiserum of NDPK-A. It also inhibited angiogenesis. CONCLUSION: PQE-nm23H1 containing 6×His can express target protein at high level. This purification method is simple than other methods, and the product has the same activity as natural human NDPK-A.  相似文献   

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