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171.
172.
Introducing Bt Gene Into Maize With Ovary Injection 总被引:1,自引:0,他引:1
It is reported here that Bt toxin gene has been successfully transferred into maize inbred line by ovary injection for the first time both at home and abroad. One transgenic plant (To) has been confirmed by Southern blotting and PCR test, and 71 progenies (T1) from T0 have been obtained through self-pollination. Of these 71 progenies, seven plants demonstrated positive results in the PCR test; four were used to feed Asian corn borer, and certain effect of insect-resistance was observed. The experiments on the ovary injection in Hainan Province have also been repeated, thus providing new chance to the application of genetic engineering to the maize improvement. 相似文献
173.
随着糖组学的发展,研究表明某些疾病如肿瘤等的发生伴随着体内糖蛋白表面糖链结构的变化,而糖链结构的形成与修饰经过糖基转移酶、糖苷酶和磺基转移酶的参与.本研究从Genebank等数据库中选取人类糖基转移酶基因127条、糖苷酶基因34条和磺基转移酶34条以及管家基因10条.通过对每个基因的mRNA序列进行探针设计,制备出一款糖类相关基因芯片,用于研究糖类相关基因的表达谱,旨在揭示疾病发生与糖类相关基因表达变化的关联性.制备的芯片应用于人肝癌细胞系SMMC-7721与正常肝细胞系Chang’s liver的研究,筛选出差异表达的基因34个,其中上调基因19个、下调基因15个.通过对2个上调基因和2个下调基因进行Realtime-PCR验证,得到了一致的实验结果. 相似文献
174.
Gha-Young Kim 《Analytica chimica acta》2010,677(1):90-8880
The development and characterization of a magnetic bead (MB)-quantum dot (QD) nanoparticles based assay capable of quantifying pathogenic bacteria is presented here. The MB-QD assay operates by having a capturing probe DNA selectively linked to the signaling probe DNA via the target genomic DNA (gDNA) during DNA hybridization. The signaling probe DNA is labeled with fluorescent QD565 which serves as a reporter. The capturing probe DNA is conjugated simultaneously to a MB and another QD655, which serve as a carrier and an internal standard, respectively. Successfully captured target gDNA is separated using a magnetic field and is quantified via a spectrofluorometer. The use of QDs (i.e., QD565/QD655) as both a fluorescence label and an internal standard increased the sensitivity of the assay. The passivation effect and the molar ratio between QD and DNA were optimized. The MB-QD assay demonstrated a detection limit of 890 zeptomolar (i.e., 10−21 mol L−1) concentration for the linear single stranded DNA (ssDNA). It also demonstrated a detection limit of 87 gene copies for double stranded DNA (dsDNA) eaeA gene extracted from pure Escherichia coli (E. coli) O157:H7 culture. Its corresponding dynamic range, sensitivity, and selectivity were also presented. Finally, the bacterial gDNA of E. coli O157:H7 was used to highlight the MB-QD assay's ability to detect below the minimum infective dose (i.e., 100 organisms) of E. coli O157:H7 in water environment. 相似文献
175.
Wei Sun Yuanyuan Zhang Anhui Hu Yongxi Lu Fan Shi Bingxin Lei Zhenfan Sun 《Electroanalysis》2013,25(6):1417-1424
In this work a partially reduced graphene oxide (p‐RGO) modified carbon ionic liquid electrode (CILE) was prepared as the platform to fabricate an electrochemical DNA sensor, which was used for the sensitive detection of target ssDNA sequence related to transgenic soybean A2704‐12 sequence. The CILE was fabricated by using 1‐butylpyridinium hexafluorophosphate as the binder and then p‐RGO was deposited on the surface of CILE by controlling the electroreduction conditions. NH2 modified ssDNA probe sequences were immobilized on the electrode surface via covalent bonds between the unreduced oxygen groups on the p‐RGO surface and the amine group at the 5′‐end of ssDNA, which was denoted as ssDNA/p‐RGO/CILE and further used to hybridize with the target ssDNA sequence. Methylene blue (MB) was used as electrochemical indicator to monitor the DNA hybridization. The reduction peak current of MB after hybridization was proportional to the concentration of target A2704‐12 ssDNA sequences in the range from 1.0×10?12 to 1.0×10?6 mol/L with a detection limit of 2.9×10?13 mol/L (3σ). The electrochemical DNA biosensor was further used for the detection of PCR products of transgenic soybean with satisfactory results. 相似文献
176.
利用已知Gelonin的氨基酸序,逆向推算出整个基因的碱基序列,根据E.coli的密码子偏爱性和后续基因克隆的需要,通过沉默突变设计相应的酶切位点和碱基序列,将整个基因分为四段,每个片段约175-220pb,每一个片段中的互补链从5′末端用化学合成100-120的碱基单链,其中两个链的3′末端有20个互补碱基。利用T4DNA聚合酶酶促添补成双链DNA,用分子克隆技术,分别构建重组子,然后再构建成含整个Gelonin基因的表达载体pET-gel进行表面,经诱导后,获得了一个28000的重组蛋白,并主要以可溶形式存在。 相似文献
177.
178.
2020年诺贝尔化学奖授予两位女性科学家——埃马纽埃尔.卡彭蒂耶和詹妮弗.杜德纳。回顾CRISPR-Cas9技术的发展史,她们完整地说明了该技术的原理、作用,并研发了CRISPR-Cas9基因编辑技术,符合诺贝尔奖奖励原创的要求,是争议最小的获奖者人选。专利和诺贝尔奖在维护发明者权益、促进科学的发展上都具有重要的作用,且不能仅以其中一项的结果判断另一项的归属,目前的归属差异不影响非商业应用的学术研究,并客观上推动了原创研究的产出。进一步思考原创的概念,明确基础科学的定位,加强对创新人才的鼓励和支持,注重诺贝尔奖颁奖历史的梳理,也是本次诺贝尔奖给予我们的启示。 相似文献
179.
Salwinder Singh Dhaliwal Vivek Sharma Arvind Kumar Shukla Vibha Verma Manmeet Kaur Yashbir Singh Shivay Shahida Nisar Ahmed Gaber Marian Brestic Viliam Barek Milan Skalicky Peter Ondrisik Akbar Hossain 《Molecules (Basel, Switzerland)》2022,27(4)
Globally, many developing countries are facing silent epidemics of nutritional deficiencies in human beings and animals. The lack of diversity in diet, i.e., cereal-based crops deficient in mineral nutrients is an additional threat to nutritional quality. The present review accounts for the significance of biofortification as a process to enhance the productivity of crops and also an agricultural solution to address the issues of nutritional security. In this endeavor, different innovative and specific biofortification approaches have been discussed for nutrient enrichment of field crops including cereals, pulses, oilseeds and fodder crops. The agronomic approach increases the micronutrient density in crops with soil and foliar application of fertilizers including amendments. The biofortification through conventional breeding approach includes the selection of efficient genotypes, practicing crossing of plants with desirable nutritional traits without sacrificing agricultural and economic productivity. However, the transgenic/biotechnological approach involves the synthesis of transgenes for micronutrient re-translocation between tissues to enhance their bioavailability. Soil microorganisms enhance nutrient content in the rhizosphere through diverse mechanisms such as synthesis, mobilization, transformations and siderophore production which accumulate more minerals in plants. Different sources of micronutrients viz. mineral solutions, chelates and nanoparticles play a pivotal role in the process of biofortification as it regulates the absorption rates and mechanisms in plants. Apart from the quality parameters, biofortification also improved the crop yield to alleviate hidden hunger thus proving to be a sustainable and cost-effective approach. Thus, this review article conveys a message for researchers about the adequate potential of biofortification to increase crop productivity and nourish the crop with additional nutrient content to provide food security and nutritional quality to humans and livestock. 相似文献
180.
随着高通量技术的发展,越来越多的生物医学组学数据亟需处理与分析,基于运筹优化的生物信息学方法是有效解析高维生物医学数据的重要途径之一。综述了近年来在基因调控网络推断方面的研究进展。针对不同类型的转录组学数据和研究目的,分别建立了相应的基因调控网络推断方法,主要包括先验基因调控网络数据库的建立、基于条件互信息的因果网络推断、基于微分方程的动态基因调控网络推断、转录调控和转录后调控协同作用的网络推断以及基因调控网络活性评价等,并展望了基因调控网络推断的重要研究方向。 相似文献