Protocol allows you to measure the content of cyclic adenosine 3',5'-monophosphate (cyclic AMP or cAMP) in splenic B lymphocytes (B cells) in an enzyme-linked immunoassay. This protocol utilizes acetylation of cAMP to improve sensitivity and reduce interference. Protocol includes information on: how to determine cAMP, calculations and reagents and materials. - [Read Assay of Cyclic AMP in Lysates of Cells]
Protocol describes a method for producing diploid embryo-tetraploid embryo chimeras. It requires the timed combination of four-cell-stage tetraploid embryo production and the procedure for diploid embryo-diploid embryo aggregation. The resulting chimeras are useful for phenotypic analysis when an induced mutation has an extraembryonic phenotype. - [Read Assembling Aggregates between Diploid and Tetraploid Embryos Protocol]
Protocol describes a method for assembling aggregates between diploid embryos. If embryos from a heterozygous mutant intercross are aggregated with wild-type embryos, the resulting chimeras can be used for analyzing mutant phenotypes. - [Read Assembling Aggregates between Diploid Embryos Protocol]
Protocol describes a method for assembling aggregates between ES cells and diploid embryos. The resulting chimeras are useful for separating certain extraembryonic phenotypes from phenotypes in the embryo proper, since the diploid embryo contributes to all parts of the conceptus, but the ES cell component does not contribute to the trophoblast or yolk sac endoderm. - [Read Assembling Aggregates between Embryonic Stem (ES) Cells and Diploid Embryos Protocol]
Protocol describes a method for producing ES cell-tetraploid embryo chimeras. It requires the timed combination of four-cell-stage tetraploid embryo production and the procedure for ES cell-diploid embryo aggregation in which diploid embryos are replaced with tetraploid embryos. The resulting chimeras can be used to analyze the embryonic versus extraembryonic phenotype of a mutation. - [Read Assembling Aggregates between Embryonic Stem (ES) Cells and Tetraploid Embryos Protocol]
Adaptors are short double-stranded synthetic oligonucleotides that carry an internal restriction endonuclease recognition site and single-stranded tails at one or both ends. Adaptors are used to exchange restriction sites at the termini of linear DNA molecules. They may be purchased in phosphorylated and unphosphorylated forms. - [Read Attaching Adaptors to Protruding Termini Protocol]
This stage achieves four goals: polishing the ends of double-stranded DNA, ligation of synthetic linkers or adaptors, digestion of the attached linkers to create cohesive termini, and preparing the cDNA for cloning. - [Read Attachment of Linkers or Adaptors for Construction of cDNA Libraries]
Protocol is for bidirectional, blunt-end cloning of DNA fragments. The target DNA is PCR amplified and 3'-extensions are polished with Pfu DNA polymerase. The amplicon is ligated to a blunt-ended plasmid DNA, and the products of the ligation reaction are used to transform competent Escherichia coli. A restriction enzyme is added to the ligation reaction to relinearize any self-religating vector DNA. - [Read Bidirectional Cloning of PCR Products Protocol]
Once tissues are fixed and permeabilized, the antibodies are added. These antibodies can be labeled directly or detected by a labeled secondary reagent. For indirect detection, any reagent that binds specifically to the primary antibody can be "tagged" and used to locate the antibody. The possible reagents include anti-immunoglobulin antibodies, protein A or G, or, if the first antibody is labeled with biotin, streptavidin. They can be labeled with enzymes or gold. - [Read Binding Antibodies to Tissue Sections Protocol]
This protocol describes a stepwise procedure to prepare nucleic acids encapsulated in a polyethylene glycol (PEG)-shielded nanolipoparticle (NLP) that contain a bioresponsive lipid and ligand. This process provides several advantages for systemic gene delivery. The in vivo circulation time is extended. Also, low pH-sensitive lipids enhance DNA unpacking and endosomal escape. Finally, ligands inserted into the NLP surface can target gene delivery to specific tissues or cells in vivo. - [Read Bioresponsive Targeted Charge Neutral Lipid Vesicles for Systemic Gene Delivery Protocol]
BN-PAGE has become the method of choice for the investigation of the respiratory protein complexes of the electron transfer chains of a range of organisms. It allows the separation in two dimensions of extremely hydrophobic protein sets for analysis and also provides information on their native interactions. In this review we discuss the capabilities of BN-PAGE in proteomics and the wider investigation of protein:protein interactions with a focus on its use and potential in plant science. - [Read Blue-Native PAGE in Plants: A Tool in Analysis of Protein-Protein Interactions]
Protocol for blunt-end cloning of PCR products. Incubation of a blunt-end ligation reaction in the presence of an excess amount of an appropriate restriction enzyme can dramatically increase the yield of recombinant plasmids. The role of the restriction enzyme is to cleave circular and linear concatemers at restriction sites that are re-formed when linear, blunt-ended plasmid molecules ligate to themselves. I - [Read Blunt-end Cloning of PCR Products Protocol]
Calcium phosphate forms an insoluble precipitate with DNA, which attaches to the cell surface and is taken into the cells by endocytosis. The protocol is easily adapted for use with other types of cells, both adherent and nonadherent. This protocol is a modified version of a method published by Jordan et al. (1996) who rigorously optimized calcium-phosphate-based transfection methods for Chinese hamster ovary cells and the 293 line of human embryonic kidney cells. - [Read Calcium-phosphate-mediated Transfection of Eukaryotic Cells with Plasmid DNAs]
This protocol describes an easy method for calibrating micropipette tips that have been pulled in the laboratory. It is essential to estimate the internal diameter of the pulled micropipette tip when adjusting parameters for a new puller or new type of glass tubing. A tip diameter of ~0.3 µm is optimal for the microinjection of mammalian cells in culture (e.g., CHO, PtK1, and COS-7). A 10% increase in diameter increases the delivery rate by more than 30% and can cause cell damage. - [Read Calibration of Micropipette Tips Protocols]
This method, for the selective amplification of full-length cDNA ends, involves the addition of an adapter during reverse transcription. This method takes advantage of the propensity of Moloney murine leukemia virus reverse transcriptase (MMLV RT) to append two to four cytosines to the 3'-end of newly synthesized cDNA strands. The additional residues are added when the enzyme reaches the 5'-cap structure at the end of the mRNA template. - [Read Cap-Switching RACE Protocol]
Information on how to quantitatively assess DNA content. Includes: Propidium iodide staining protocol and staining of DNA by Mithramicin Protocol - [Read Cell Cycle Analysis - Propidium Iodide]
In Vitro Translated Xenopus Mos Kinase Assay Protocol. In response to progesterone, immature Xenopus oocytes mature to eggs that can be fertilized. The Mos protein kinase is essential for oocyte maturation, most likely due to its ability to activate the MAP kinase cascade. This MAP kinase cascade eventually leads to the activation of Cdc2/cyclin B and entry into M phase. In this protocol, tagged Mos kinase is translated in vitro, immunopurified, and used in a kinase assay.