<ol><li>改造，板3 - 5X10 6细胞/ 6厘米的组织cultureplate 293T细胞前的晚上。 注：我们使用易于转染和efficacyas病毒产生细胞的293T细胞 。 这些细胞是缺乏包装病毒的，除非引入一个辅助质粒。 </li><li>第一天上午，轻轻取出介质替换为4毫升293T细胞MED含有氯喹25毫米。培养箱中培养1小时。 注：板应在80％左右融合。 </li><li>同时，病毒混合2板准备的时间，在5毫升管： <ol><li> 2 × 10毫克逆转录病毒质粒的构建</li><li> 2 × 5毫克的包装构造（EcoPak） </li><li> 2 × 62毫升氯化钙</li><li>完成至1 ml，用无菌DDH 2 O 注：虽然逆转录病毒质粒编码的兴趣和标记的癌基因，EcoPak编码GAG - POL - ENV。 连同293T细胞时，就会产生ecotropic逆转录病毒（RV）的特定的小鼠细胞，但不会对人体细胞的感染 。 氯喹和氯化钙2已被证明能增加转染效率。 </li></ol></li><li>添加2X sterileHBS1毫升下降明智的混合物，一边轻轻振荡管。 </li><li>立即加入该解决方案2板，每1毫升，轻轻地，一滴一滴。 </li><li>培养箱中培养7至11小时。 </li><li>在今晚（7日至11小时以后），轻轻取出介质，轻轻地取代用5毫升的新鲜293T中等。培养箱中培养，直到中午，第二天。 注：这一步很重要，因为你需要从细胞中的氯喹起飞。如果长时间保存，氯是有毒的。在板块的解决方案看起来很模糊，由于非常精细，尘埃状沉淀转染混合物。 注：重要的是做极端温柔的所有媒体的变化，细胞已致敏的氯喹，可以很容易地脱离板 。 </li><li>第二天，18至24小时。检索病毒（约中午）之前，轻轻取出介质，非常轻柔3毫升新鲜293T中型取代。替换在孵化器的O / N。 </li><li>第三天早上（18至24小时。以后），轻轻吸了10毫升注射器配有一个18 G针中期形成的板块。这上清包含的逆转录病毒。 </li><li>更改针到45毫米的注射器过滤器，倒置注射器多次组合的解决方案，通过过滤上清液，cryotubes等分 注：此外，如果你正在为5 0 ml锥形管3 +病毒，池中所有相同的病毒上清板块。拌匀，然后分装上清含有cryotubes逆转录病毒过滤。 </li><li>管含有病毒的全上清保存在-80℃直至使用。 </li></ol>

<ol>
	<li>DuBridge, R. B., Tang, P., Hsia, H. C., Leong, P. M., Miller, J. H., Calos, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+mutation+in+human+cells+by+using+an+Epstein-Barr+virus+shuttle+system.">Analysis of mutation in human cells by using an Epstein-Barr virus shuttle system.</a> Mol Cell Biol. 7, 379-387 (1987).</li><li>Cherry, S. R., Biniszkiewicz, D., van Parijs, L., Baltimore, D., Jaenisch, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retroviral+expression+in+embryonic+stem+cells+and+hematopoietic+stem+cells.">Retroviral expression in embryonic stem cells and hematopoietic stem cells.</a> Mol Cell Biol. 20, 7419-7426 (2000).</li><li>Finer, M. H., Dull, T. J., Qin, L., Farson, D., Roberts, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=kat:+A+high-efficiency+retroviral+transduction+system+for+primary+human+T+lymphocytes.">kat: A high-efficiency retroviral transduction system for primary human T lymphocytes.</a> Blood. 83, 43-50 (1994).</li><li>Naviaux, R. K., Costanzi, E., Haas, M., Verma, I. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pCL+vector+system:+rapid+production+of+helper-free,+high-titer,+recombinant+retroviruses.">The pCL vector system: rapid production of helper-free, high-titer, recombinant retroviruses.</a> J Virol. 70, 5701-5705 (1996).</li><li>Pear, W. S., Miller, J. P., Xu, L., Pui, J. C., Soffer, B., Quackenbush, R. C., Pendergast, A. M., Bronson, R., Aster, J. C., Scott, M. L., Baltimore, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+and+rapid+induction+of+a+chronic+myelogenous+leukemia-like+myeloproliferative+disease+in+mice+receiving+P210+bcr/abl-transduced+bone+marrow.">Efficient and rapid induction of a chronic myelogenous leukemia-like myeloproliferative disease in mice receiving P210 bcr/abl-transduced bone marrow.</a> Blood. 92, 3780-3792 (1998).</li><li>Pear, W. S., Nolan, G. P., Scott, M. L., Baltimore, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+of+high-titer+helper-free+retroviruses+by+transient+transfection.">Production of high-titer helper-free retroviruses by transient transfection.</a> Proc Natl Acad Sci USA. 90, 8392-8396 (1993).</li><li>Stocking, C., Kollek, R., Bergholz, U., Ostertag, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long+terminal+repeat+sequences+impart+hematopoietic+transformation+properties+to+the+myeloproliferative+sarcoma+virus.">Long terminal repeat sequences impart hematopoietic transformation properties to the myeloproliferative sarcoma virus.</a> Proc Natl Acad Sci USA. 82, 5746-5750 (1985).</li><li>Van Etten, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Models+of+chronic+myeloid+leukemia.">Models of chronic myeloid leukemia.</a> Curr Oncol Rep. 3, 228-237 (2001).</li><li>Van Etten, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+the+pathogenesis+of+BCR-ABL++leukemia+in+mice.">Studying the pathogenesis of BCR-ABL+ leukemia in mice.</a> Oncogene. 21, 8643-8651 (2002).</li></ol>

四个关键点，将保证一个良好的病毒股票的成功： <ol><li>生产的293T细胞很健康，这意味着他们已经非常有规律的时间表上的分裂，从来没有杂草丛生，并在组织培养板，每6厘米的3.5-5万的优化密度镀，使他们达到一个密度80％的板转染上午。 </li><li>此外氯喹，提高转染效率和随后的病毒滴度，约3 - 5倍，稳定细胞lysozomes和增加到达细胞核内的DNA的一小部分。丁酸钠（另一种溶酶体稳定）也被用于这一...

在转染所使用的所有试剂必须是无菌的过滤（ 氯化钙 ，2个哈佛商学院，H 2 O miliQ），并保持无菌。

production of replication-defective retrovirus by transient transfection of 293t cells

我们的实验室研究人类Bcr - Abl的或生长因子受体产生的致癌基因（ZNF198 - FGFR1的，BCR -PDGFRα等）等癌基因诱导骨髓增生性疾病。我们能够在我们的小鼠模型，以模型和研究一个与人类类似的的疾病，以前与利益表达的原癌基因的逆转录病毒感染的骨髓细胞移植。复制缺陷的逆转录病毒编码的人类癌基因和标记（GFP，RFP，耐抗生素基因等）是产生一个瞬时转染293T细胞，腺病毒E1A基因产品转化一个人的肾上皮细胞系的协议。 293细胞有高度磷酸三钙（投诉警察课4）转染不同寻常的特性，容易达到50-80％的转染效率。在这里，我们共同利益和质粒表达GAG - POL - ENV包装的功能，如包装构造吉或PCL，在这种情况下的单基因质粒EcoPak，的原癌基因表达逆转录病毒载体转染293细胞。最初的转染，进一步提高使用氯喹。 ecotropic病毒的股票，收集培养上清48小时。转染后，可以储存在-80 ° C和用于感染细胞系，改造和体外研究，或小鼠骨髓细胞如原代细胞，在我们的小鼠模型，然后可以用于移植。

Watch this Scientific Journal Video about Production of Replication-Defective Retrovirus by Transient Transfection of 293T cells at JoVE.com

自然选择|生物学视频集

Production of Replication-Defective Retrovirus by Transient Transfection of 293T cells

这种技术演示了一个有效的方式来准备复制缺陷型逆转录病毒编码的人类癌基因的股票，随后诱导骨髓增殖性疾病的小鼠模型中使用。

瞬时转染293T细胞复制缺陷型逆转录病毒生产

Our lab studies human myeloproliferative diseases induced by such oncogenes as Bcr-Abl or growth factor receptor-derived oncogenes (ZNF198-FGFR1, ...

production-replication-defective-retrovirus-transient-transfection

Research

JoVE Journal

Biology

19.5K 次观看.  Tufts University. 这种技术演示了一个有效的方式来准备复制缺陷型逆转录病毒编码的人类癌基因的股票，随后诱导骨髓增殖性疾病的小鼠模型中使用。

视频: Production of Replication-Defective Retrovirus by Transient Transfection of 293T cells

Gene-gun Transfection of Hippocampal Neurons

Hi, I'm Kma. I work in Case Lab at Brown University Clean Slicer stage with 70%ethanol. Place plate insert into six.Well plate with medium and incubate at 37 degree whole brain with tweezers between midbrain and four brainin. Isolate hippocampus on one side, isolate hippocampus from the second side. Place hippocampi onto A PBS drop.Aspirate out the PBS make sagittal sections using the tissue slicer. Repeat transfer slicers onto a perish by squatting with PBS wash sections by adding and aspirating PBS and medium gently. Separate sections with tweezers.Wash sections with PBS and media. Again, transfer sections onto the plate and insert. Aspirate out the media in sections using tweezers.Attach gene gun hose to the helium cylinder. Attach barrel to gene gun. Fill the magazine with bullets.Insert magazine into the Jing gun. Adjust the pressure on the helium tank shoot. EGFP coated beads onto the sections.And now.

海马神经元的基因枪转

科研

生物学

A Method For Production of Recombinant mCD1d Protein in Insect Cells.

CD1 proteins constitute a third class of antigen-presenting molecules. They are cell surface glycoproteins, expressed as approximately 50-kDa glycosylated heavy chains that are noncovalently associated with beta2-microglobulin. They bind lipids rather than peptides. Although their structure confirms the similarity of CD1 proteins to MHC class I and class II antigen presenting molecules, the mCD1d groove is relatively narrow, deep, and highly hydrophobic and it has two binding pockets instead of the several shallow pockets described for the classical MHC-encoded antigen-presenting molecules. Based upon their amino acid sequences, such a hydrobphobic groove provides an ideal environment for the binding of lipid antigens. The Natural Killer T (NKT) cells use their TCR to recognize glycolipids bound to or presented by CD1d. T cells reactive to lipids presented by CD1 have been involved in the protection against autoimmune and infectious diseases and in tumor rejection. Thus, the ability to identify, purify , and track the response of CD1-reactive NKT cell is of great importance . The generation of tetramers of alpha Galactosyl ceramide (a-Galcer) with CD1d has significant insight into the biology of NKT cells. Tetramers constructed from other CD1 molecules have also been generated and these new reagents have greatly expanded the knowledge of the functions of lipid-reactive T cells, with potential use in monitoring the response to lipid-based vaccines and in the diagnosis of autoimmune diseases and other treatments.

A Method to prepare Insect cells and infect them with baculovirus for the the purpose of production of recombinant mCD1d proteinand generating mCD1d tetramers.

重组昆虫细胞中的mCD1d的蛋白质的生产方法。

CD1 proteins constitute a third class of antigen-presenting molecules. They are cell surface glycoproteins, expressed as approximately 50-kDa glycosylated ...

Production of Transgenic Xenopus laevis by Restriction Enzyme Mediated Integration and Nuclear Transplantation

Stable integration of cloned gene products into the Xenopus genome is necessary to control the time and place of expression, to express genes at later stages of embryonic development, and to define how enhancers and promoters regulate gene expression within the embryo. The protocol demonstrated here can be used to efficiently produce transgenic Xenopus laevis embryos. This transgenesis approach involves three parts: 1. Sperm nuclei are isolated from adult X. laevis testis by treatment with lysolecithin, which permeabilizes the sperm plasma membrane. 2. Egg extract is prepared by low speed centrifugation, addition of calcium to cause the extract to progress to interphase of the cell cycle, and a high-speed centrifugation to isolate interphase cytosol. 3. Nuclear transplantation: the nuclei and extract are combined with the linearized plasmid DNA to be introduced as the transgene and a small amount of restriction enzyme. During a short reaction, egg extract partially decondenses the sperm chromatin and the restriction enzyme generates chromosomal breaks that promote recombination of the transgene into the genome. The treated sperm nuclei are then transplanted into unfertilized eggs. Integration of the transgene usually occurs prior to the first embryonic cleavage such that the resulting embryos are not chimeric. These embryos can be analyzed without any need to breed to the next generation, allowing for efficient and rapid generation of transgenic embryos for analyses of promoter and gene function. Adult X. laevis resulting from this procedure also propagate the transgene through the germline and can be used to generate lines of transgenic animals for multiple purposes.

Production of Transgenic Xenopus laevis by Restriction Enzyme Mediated Integration and Nuclear Transplantation

This video protocol demonstrates a method for generating transgenic Xenopus laevis by introduction of transgenes into sperm nuclei followed by nuclear transplantation into unfertilized eggs.

生产转基因非洲爪蟾限制性内切酶介导的整合和核移植

Stable integration of cloned gene products into the Xenopus genome is necessary to control the time and place of expression, to express genes at later ...

Optimized Transfection Strategy for Expression and Electrophysiological Recording of Recombinant Voltage-Gated Ion Channels in HEK-293T Cells

The in vitro expression and electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T) is a ubiquitous research strategy. HEK-293T cells must be plated onto glass coverslips at low enough density so that they are not in contact with each other in order to allow for electrophysiological recording without confounding effects due to contact with adjacent cells. Transfected channels must also express with high efficiency at the plasma membrane for whole-cell patch clamp recording of detectable currents above noise levels. Heterologous ion channels often require long incubation periods at 28&deg;C after transfection in order to achieve adequate membrane expression, but there are increasing losses of cell-coverslip adhesion and membrane stability at this temperature. To circumvent this problem, we developed an optimized strategy to transfect and plate HEK-293T cells. This method requires that cells be transfected at a relatively high confluency, and incubated at 28&deg;C for varying incubation periods post-transfection to allow for adequate ion channel protein expression. Transfected cells are then plated onto glass coverslips and incubated at 37&deg;C for several hours, which allows for rigid cell attachment to the coverslips and membrane restabilization. Cells can be recorded shortly after plating, or can be transferred to 28&deg;C for further incubation. We find that the initial incubation at 28&deg;C, after transfection but before plating, is key for the efficient expression of heterologous ion channels that normally do not express well at the plasma membrane. Positively transfected, cultured cells are identified by co-expressed eGFP or eGFP expressed from a bicistronic vector (e.g. pIRES2-EGFP) containing the recombinant ion channel cDNA just upstream of an internal ribosome entry site and an eGFP coding sequence. Whole-cell patch clamp recording requires specialized equipment, plus the crafting of polished recording electrodes and L-shaped ground electrodes from borosilicate glass. Drug delivery to study the pharmacology of ion channels can be achieved by directly micropipetting drugs into the recording dish, or by using microperfusion or gravity flow systems that produce uninterrupted streams of drug solution over recorded cells.

Reliable method for highly efficient in vitro expression and subsequent electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T).

优化转染的HEK - 293T细胞中的表达和重组的电压门控离子通道的电生理记录策略

The in vitro expression and electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T) ...

In vitro Transcription and Capping of Gaussia Luciferase mRNA Followed by HeLa Cell Transfection

In vitro transcription is the synthesis of RNA transcripts by RNA polymerase from a linear DNA template containing the corresponding promoter sequence (T7, T3, SP6) and the gene to be transcribed (Figure 1A). A typical transcription reaction consists of the template DNA, RNA polymerase, ribonucleotide triphosphates, RNase inhibitor and buffer containing Mg2+ ions.
Large amounts of high quality RNA are often required for a variety of applications. Use of in vitro transcription has been reported for RNA structure and function studies such as splicing1, RNAi experiments in mammalian cells2, antisense RNA amplification by the "Eberwine method"3, microarray analysis4 and for RNA vaccine studies5. The technique can also be used for producing radiolabeled and dye labeled probes6. Warren, et al. recently reported reprogramming of human cells by transfection with in vitro transcribed capped RNA7. The T7 High Yield RNA Synthesis Kit from New England Biolabs has been designed to synthesize up to 180 &mu;g RNA per 20 &mu;l reaction. RNA of length up to 10kb has been successfully transcribed using this kit. Linearized plasmid DNA, PCR products and synthetic DNA oligonucleotides can be used as templates for transcription as long as they have the T7 promoter sequence upstream of the gene to be transcribed.
Addition of a 5' end cap structure to the RNA is an important process in eukaryotes. It is essential for RNA stability8, efficient translation9, nuclear transport10 and splicing11. The process involves addition of a 7-methylguanosine cap at the 5' triphosphate end of the RNA. RNA capping can be carried out post-transcriptionally using capping enzymes or co-transcriptionally using cap analogs. In the enzymatic method, the mRNA is capped using the Vaccinia virus capping enzyme12,13. The enzyme adds on a 7-methylguanosine cap at the 5' end of the RNA using GTP and S-adenosyl methionine as donors (cap 0 structure). Both methods yield functionally active capped RNA suitable for transfection or other applications14 such as generating viral genomic RNA for reverse-genetic systems15 and crystallographic studies of cap binding proteins such as eIF4E16.
In the method described below, the T7 High Yield RNA Synthesis Kit from NEB is used to synthesize capped and uncapped RNA transcripts of Gaussia luciferase (GLuc) and Cypridina luciferase (CLuc). A portion of the uncapped GLuc RNA is capped using the Vaccinia Capping System (NEB). A linearized plasmid containing the GLuc or CLuc gene and T7 promoter is used as the template DNA. The transcribed RNA is transfected into HeLa cells and cell culture supernatants are assayed for luciferase activity. Capped CLuc RNA is used as the internal control to normalize GLuc expression.

In vitro Transcription and Capping of Gaussia Luciferase mRNA Followed by HeLa Cell Transfection

This method describes high yield in vitro synthesis of both capped and uncapped mRNA from a linearized plasmid containing the Gaussia luciferase (GLuc) gene. The RNA is purified and a fraction of the uncapped RNA is enzymatically capped using the Vaccinia virus capping enzyme. In the final step, the mRNA is transfected into HeLa cells and cell culture supernatants are assayed for luciferase activity.

在体外转录和Gaussia荧光素酶基因的上限由HeLa细胞转染

In vitro transcription is the synthesis of RNA transcripts by RNA polymerase from a linear DNA template containing the corresponding promoter sequence ...

Protein Transfection of Mouse Lung

Increasing protein expression enables researchers to better understand the functional role of that protein in regulating key biological processes1. In the lung, this has been achieved typically through genetic approaches that utilize transgenic mice2,3 or viral or non-viral vectors that elevate protein levels via increased gene expression4. Transgenic mice are costly and time-consuming to generate and the random insertion of a transgene or chronic gene expression can alter normal lung development and thus limit the utility of the model5. While conditional transgenics avert problems associated with chronic gene expression6, the reverse tetracycline-controlled transactivator (rtTA) mice, which are used to generate conditional expression, develop spontaneous air space enlargement7. As with transgenics, the use of viral and non-viral vectors is expensive8 and can provoke dose-dependent inflammatory responses that confound results9 and hinder expression10. Moreover, the efficacy of repeated doses are limited by enhanced immune responses to the vector11,12. Researchers are developing adeno-associated viral (AAV) vectors that provoke less inflammation and have longer expression within the lung13.
Using &beta;-galactosidase, we present a method for rapidly and effectively increasing protein expression within the lung using a direct protein transfection technique. This protocol mixes a fixed amount of purified protein with 20 &mu;l of a lipid-based transfection reagent (Pro-Ject, Pierce Bio) to allow penetration into the lung tissue itself. The liposomal protein mixture is then injected into the lungs of the mice via the trachea using a microsprayer (Penn Century, Philadelphia, PA). The microsprayer generates a fine plume of liquid aerosol throughout the lungs. Using the technique we have demonstrated uniform deposition of the injected protein throughout the airways and the alveoli of mice14. The lipid transfection technique allows the use of a small amount of protein to achieve effect. This limits the inflammatory response that otherwise would be provoked by high protein administration. Indeed, using this technique we published that we were able to significantly increase PP2A activity in the lung without affecting lung lavage cellularity15. Lung lavage cellularity taken 24 hr after challenge was comparable to controls (27&plusmn;4 control vs. 31&plusmn;5 albumin transfected; N=6 per group). Moreover, it increases protein levels without inducing lung developmental changes or architectural changes that can occur in transgenic models. However, the need for repeated administrations may make this technique less favorable for studies examining the effects of long-term increases in protein expression. This would be particularly true for proteins with short half-lives.

Transgenic mice or viral vectors have been used to increase protein expression within the lung. However, these techniques are time-consuming, technically challenging and have off-target effects that can confound results. Our protein transfection protocol uses a lipid based transfection reagent and an ultrafine microsprayer to uniformly deliver active protein to lung cells.

蛋白转染小鼠肺

Increasing protein expression enables researchers to  better understand the functional role of that protein in regulating key  biological processes1. In ...

Optimization and Utilization of Agrobacterium-mediated Transient Protein Production in Nicotiana

Agrobacterium-mediated transient protein production in plants is a promising approach to produce vaccine antigens and therapeutic proteins within a short period of time. However, this technology is only just beginning to be applied to large-scale production as many technological obstacles to scale up are now being overcome. Here, we demonstrate a simple and reproducible method for industrial-scale transient protein production based on vacuum infiltration of Nicotiana plants with Agrobacteria carrying launch vectors. Optimization of Agrobacterium cultivation in AB medium allows direct dilution of the bacterial culture in Milli-Q water, simplifying the infiltration process. Among three tested species of Nicotiana, N. excelsiana (N. benthamiana &#215; N. excelsior) was selected as the most promising host due to the ease of infiltration, high level of reporter protein production, and about two-fold higher biomass production under controlled environmental conditions. Induction of Agrobacterium harboring pBID4-GFP (Tobacco mosaic virus-based) using chemicals such as acetosyringone and monosaccharide had no effect on the protein production level. Infiltrating plant under 50 to 100 mbar for 30 or 60 sec resulted in about 95% infiltration of plant leaf tissues. Infiltration with Agrobacterium laboratory strain GV3101 showed the highest protein production compared to Agrobacteria laboratory strains LBA4404 and C58C1 and wild-type Agrobacteria strains at6, at10, at77 and A4. Co-expression of a viral RNA silencing suppressor, p23 or p19, in N. benthamiana resulted in earlier accumulation and increased production (15-25%) of target protein (influenza virus hemagglutinin).

Optimization and Utilization of Agrobacterium-mediated Transient Protein Production in Nicotiana

Transient protein production in Nicotiana plants based on vacuum infiltration with Agrobacteria carrying launch vectors (Tobacco mosaic virus-based) is a rapid and economic approach to produce vaccine antigens and therapeutic proteins. We simplified the procedure and improved target accumulation by optimizing conditions of bacteria cultivation, selecting host species, and co-introducing RNA silencing suppressors.

优化和利用<em&gt;农杆菌</em&gt;介导的瞬态蛋白生产中<em&gt;烟草</em

Agrobacterium-mediated transient protein production in plants is a promising approach to produce vaccine antigens and therapeutic proteins within a short ...

Transient Expression of Proteins by Hydrodynamic Gene Delivery in Mice

Efficient expression of transgenes in vivo is of critical importance in studying gene function and developing treatments for diseases. Over the past years, hydrodynamic gene delivery (HGD) has emerged as a simple, fast, safe and effective method for delivering transgenes into rodents. This technique relies on the force generated by the rapid injection of a large volume of physiological solution to increase the permeability of cell membranes of perfused organs and thus deliver DNA into cells. One of the main advantages of HGD is the ability to introduce transgenes into mammalian cells using naked plasmid DNA (pDNA). Introducing an exogenous gene using a plasmid is minimally laborious, highly efficient and, contrary to viral carriers, remarkably safe. HGD was initially used to deliver genes into mice, it is now used to deliver a wide range of substances, including oligonucleotides, artificial chromosomes, RNA, proteins and small molecules into mice, rats and, to a limited degree, other animals. This protocol describes HGD in mice and focuses on three key aspects of the method that are critical to performing the procedure successfully: correct insertion of the needle into the vein, the volume of injection and the speed of delivery. Examples are given to show the application of this method to the transient expression of two genes that encode secreted, primate-specific proteins, apolipoprotein L-I (APOL-I) and haptoglobin-related protein (HPR).

In vivo transfection of naked DNA by hydrodynamic gene delivery introduces genes into the tissue of an animal with minimal inflammatory response. Sufficient amounts of gene product are generated such that gene function and regulation as well as protein structure and function can be analyzed.

蛋白通过流体动力基因传递在小鼠体内瞬时表达

Efficient expression of transgenes in vivo is of critical importance in studying gene function and developing treatments for diseases. Over the past ...

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) maintain the turnover of all mature blood cell lineages. The coordination of the complex signals leading to specific HSC fates relies upon the interaction between HSCs and the intricate bone marrow microenvironment, which is still poorly understood[1-2].
We describe how by combining a newly developed specimen holder for stable animal positioning with multi-step confocal and two-photon in vivo imaging techniques, it is possible to obtain high-resolution 3D stacks containing HSPCs and their surrounding niches and to monitor them over time through multi-point time-lapse imaging. High definition imaging allows detecting ex vivo labeled hematopoietic stem and progenitor cells (HSPCs) residing within the bone marrow. Moreover, multi-point time-lapse 3D imaging, obtained with faster acquisition settings, provides accurate information about HSPC movement and the reciprocal interactions between HSPCs and stroma cells.
Tracking of HSPCs in relation to GFP positive osteoblastic cells is shown as an exemplary application of this method. This technique can be utilized to track any appropriately labeled hematopoietic or stromal cell of interest within the mouse calvarium bone marrow space.

In Vivo 4-Dimensional Tracking of Hematopoietic Stem and Progenitor Cells in Adult Mouse Calvarial Bone Marrow

The nature of the interactions between hematopoietic stem and progenitor cells (HSPCs) and bone marrow niches is poorly understood. Custom hardware modifications and a multi-step acquisition protocol allow the use of two-photon and confocal microscopy to image ex vivo labeled HSPCs homed within bone marrow areas, tracking interactions and movement.

在造血干细胞和祖细胞的成年小鼠颅骨骨髓体内四维跟踪

Through a delicate balance between quiescence and proliferation, self renewal and production of differentiated progeny, hematopoietic stem cells (HSCs) ...

Production of Haploid Zebrafish Embryos by In Vitro Fertilization

The zebrafish has become a mainstream vertebrate model that is relevant for many disciplines of scientific study. Zebrafish are especially well suited for forward genetic analysis of developmental processes due to their external fertilization, embryonic size, rapid ontogeny, and optical clarity &#8211; a constellation of traits that enable the direct observation of events ranging from gastrulation to organogenesis with a basic stereomicroscope. Further, zebrafish embryos can survive for several days in the haploid state. The production of haploid embryos in vitro is a powerful tool for mutational analysis, as it enables the identification of recessive mutant alleles present in first generation (F1) female carriers following mutagenesis in the parental (P) generation. This approach eliminates the necessity to raise multiple generations (F2, F3, etc.) which involves breeding of mutant families, thus saving the researcher time along with reducing the needs for zebrafish colony space, labor, and the husbandry costs. Although zebrafish have been used to conduct forward screens for the past several decades, there has been a steady expansion of transgenic and genome editing tools. These tools now offer a plethora of ways to create nuanced assays for next generation screens that can be used to further dissect the gene regulatory networks that drive vertebrate ontogeny. Here, we describe how to prepare haploid zebrafish embryos. This protocol can be implemented for novel future haploid screens, such as in enhancer and suppressor screens, to address the mechanisms of development for a broad number of processes and tissues that form during early embryonic stages.

Production of Haploid Zebrafish Embryos by In Vitro Fertilization

The zebrafish is a powerful model system for developmental biology and human disease research due to their genetic similarity with higher vertebrates. This protocol describes a methodology to create haploid zebrafish embryos that can be utilized for forward screen strategies to identify recessive mutations in genes essential for early embryogenesis.

生产单倍体斑马鱼的胚胎通过<em&gt;体外</em&gt;施肥

The zebrafish has become a mainstream vertebrate model that is relevant for many disciplines of scientific study. Zebrafish are especially well suited for ...