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991.
簇毛麦基因组特异性PCR标记的建立和应用   总被引:10,自引:0,他引:10  
以普通小麦中国春、簇毛麦、中国春-簇毛麦二体附加系和代换系为材料进行RAPD分析,筛选出一个簇毛麦基因组特异性RAPD片段OPFO2757,该片段分布于簇毛麦所有染色体上。在对OPFO2757进行克隆、测序的基础上,设计一对PCR引物,建立了簇毛麦基因组特异性PCR标记。用这对PCR引物对不同普通小麦品种、不同硬粒小麦品种、不同居群的簇毛麦、中国春-簇毛麦二体附加系、中国春-簇毛麦二体代换系、普通小麦-簇毛麦双二倍体、硬粒小麦-簇毛麦双二倍体等材料进行扩增,凡具有簇毛麦染色体的材料都能扩增出一条长为677bp的DNA片段,而不具簇毛麦染色体的材料包括大麦、黑麦、长穗偃麦草、中间偃麦草等不能扩增出该片段。所以,该特异性PCR标记可用于快速跟踪检测小麦背景中的簇毛麦染色体。  相似文献   
992.
To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development.  相似文献   
993.
Six natural media were examined for growth and sporulation of six isolates of the nematophagous fungus Hirsutella rhossiliensis , using solid and/or liquid culture. Twenty carbohydrates, 19 nitrogen (N) compounds, and nine vitamins were also tested for their effects on growth, sporulation, and spore germination of a further three isolates (ATCC46487, OWVT-1 and JA16-1). Variations in nutritional requirements existed among the fungal isolates. In general, V-8 juice agar (VA), cornmeal agar and potato dextrose agar were good media for growth, and malt extract agar, VA and yeast dextrose agar were good for sporulation of all six isolates. Glycogen was the best and sucrose, inulin, D- ( + ) - trehalose and soluble starch were also good carbon (C) sources for growth and spore germination of the three isolates ATCC46487, OWVT-1 and JA16-1 in both liquid and solid culture. None of the isolates utilized D- ( + )xylose as a C source. L- sorbose, D- ribose, citric acid and D- fructose were poor for growth of all isolates. The best C source for sporulation was D- ( + )-trehalose for ATCC46487, D- sorbitol for OWVT-1 and D- ( + )-cellobiose for JA16-1. Casein was the best N source for growth of ATCC46487 and OWVT-1, while peptone was best for JA16-1. L- asparagine, L- proline, and peptone were also good for growth of all three isolates. L - cystine was not utilized by H. rhossiliensis and DL- methionine inhibited growth of all isolates. Spore germination of all isolates was well supported by most N compounds examined but was inhibited by L- cystine. No significant difference in sporulation of ATCC46487 was observed among the N sources. DL- threonine was the best N source for spore production by OWVT-1 and L- phenylalanine was best for JA16-1. Vitamins generally enhanced fungal growth and sporulation, with thiamine having the greatest influence. Excluding some vitamins individually from the medium containing all other test vitamins sometimes increased growth and/or sporulation of certain isolates.  相似文献   
994.
Homeobox genes, widely distributed among animal and plant kingdoms, play an important role in developmental process. Several homeobox conserved fragments were amplified by PCR and the flanking regions were also obtained by an LM-PCR procedure. Sequencing and Southern analysis showed that they belong to a homeobox gene family of rice. Six homeobox-containing fragments were mapped on the molecular linkage map of rice. They were located on chromosomes 3, 4 and 7 respectively. It is noteworthy that there are 4 homeobox fragments located on rice chromosome 3 and the result is also consistent with the comparative genomics between rice and maize.  相似文献   
995.
羊毛的主要成分是角蛋白,其组分高甘氨酸-酪氨酸蛋白(HGTP)家族成员KAP6、KAP7和KAP8基因表达对羊毛细度和弯曲等特性具有重要影响。本文从羊毛的组成、角蛋白的生物学特征以及HGTP基因定位和表达对细度的影响等方面进行了综述,旨在为羊毛发育调控研究提供理论参考。  相似文献   
996.
The 2011 JIPB Editorial Board Meeting,which coincided with the 2011 International Symposium on Integrative Plant Biology,was held at Lanzhou University,China,on August 26,2011.Over thirty editors were in attendance for this extremely productive event (Figure 1).The symposium,jointly organized by JIPB,Lanzhou University and four Chinese societies involved in plant science research,the Chinese Society for Cell Biology,Botanical Society of China,Genetics Society of China,and Chinese Society for Plant Physiology,drew nearly 400 participants from all over China and abroad.  相似文献   
997.
Purification of photosystem Ⅱ (PSII) core complexes is a time-consuming and low-efficiency process. In order to isolate pure and active PSII core complexes in large amounts, we have developed a fast method to isolate highly active monomeric and dimeric PSII core complexes from spinach leaves by using sucrose gradient ultracentrifugation. By using a vertical rotor the process was completed significantly faster compared with a swing-out rotor. In order to keep the core complexes in high activity, the whole isolation procedure was performed in the presence of glycine betain and pH at 6.3. The isolated pigment-protein complexes were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, absorption spectroscopy, 77 K fluorescence spectroscopy and high performance liquid chromatography. Our results show that this method is a better choice for quick and efficient isolation of functionally active PSII core complexes.  相似文献   
998.
【目的】获得大豆根际土壤中溶磷能力较强的菌株,明确在菌株溶磷过程中葡萄糖脱氢酶(GDH)的作用特点及其基因的表达水平。【方法】利用溶磷圈方法分离与纯化溶磷菌株,采用Vitek 2系统和16S r RNA序列分析菌株的分类地位;测定2菌株的溶磷量、GDH活性,并根据GDH基因的保守区序列设计引物,克隆GDH基因,利用实时荧光定量PCR测定不同条件下基因的相对表达量。【结果】筛选出2株具有较强溶磷能力的溶磷菌,分别鉴定为Pseudomonas sp.和Enterobacter sp.,2菌株最高溶磷量分别为558μg/m L和478μg/m L;成功地克隆了2株溶磷菌的GDH基因,片段大小分别为2007 bp和2066 bp;2菌株在不同磷源、不同p H值培养基中GDH活性及基因表达量不同,菌株wj1在高磷条件下基因表达量最高,磷胁迫条件下基因表达量较低,而wj3在不同磷源条件下GDH基因表达量都较低。且GDH基因表达量及酶活的变化与wj3菌株溶磷量没有直接的关系。【结论】从大豆根际土壤中分离获得溶磷能力较强的菌株Pseudomonas sp.wj1和Enterobacter sp.Wj3,GDH活性及基因表达在2株菌溶磷过程中具有不同的作用特点,2菌株溶磷机制不完全相同。  相似文献   
999.
1000.
Here we provide experimental evidence that identifies JAK3 as one of the regulators of platelet function. Treatment of platelets with thrombin induced tyrosine phosphorylation of the JAK3 target substrates STAT1 and STAT3. Platelets from JAK3-deficient mice displayed a decrease in tyrosine phosphorylation of STAT1 and STAT3. In accordance with these data, pretreatment of human platelets with the JAK3 inhibitor WHI-P131 markedly decreased the base-line enzymatic activity of constitutively active JAK3 and abolished the thrombin-induced tyrosine phosphorylation of STAT1 and STAT3. Following thrombin stimulation, WHI-P131-treated platelets did not undergo shape changes indicative of activation such as pseudopod formation. WHI-P131 inhibited thrombin-induced degranulation/serotonin release as well as platelet aggregation. Highly effective platelet inhibitory plasma concentrations of WHI-P131 were achieved in mice without toxicity. WHI-P131 prolonged the bleeding time of mice in a dose-dependent manner and improved event-free survival in a mouse model of thromboplastin-induced generalized and invariably fatal thromboembolism. To our knowledge, WHI-P131 is the first anti-thrombotic agent that prevents platelet aggregation by inhibiting JAK3.  相似文献   
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