Peroxisomes can be purified in self-generated iodixanol gradients in high yield (80-90%) with no detectable contamination from any other organelle. In iodixanol peroxisomes are the densest of the major subcellular organelles (ρ = 1.18-1.20 g/ml) present in the light mitochondrial fraction from
mammalian tissues and cells. - [Read Purification of Peroxisomes in a Self-Generated Gradient]
Peroxisomes can be purified in iodixanol gradients in high yield (80-90%) with no detectable contamination from any other organelle. This is a property unique to iodixanol because the
densities of other organelles, particularly that of mitochondria (approx ρ = 1.14 g/ml) and endoplasmic reticulum (approx ρ = 1.13 g/ml) are much lower than that of peroxisomes (approx ρ = 1.18 g/ml). - [Read Purification of Peroxisomes using a Density Barrier in a Swinging-Bucket Rotor]
Purification of poly(A)+ RNA from total RNA. Hideaki Shiraishi, Kyoto University. The protocol employs Oligotex-dT30 for poly(A)+ RNA purification. - [Read Purification of poly(A)+ RNA from total RNA]
Protocol describes a general method for the purification of protein using dye-ligand affinity chromatography. The effectiveness of this protocol is dependent upon the reader having previously determined the optimal dye and buffer conditions to use for binding and eluting the protein(s) of interest. - [Read Purification of Protein Using Dye-Ligand Affinity Chromatography Protocol]
Single-step technique, cells are homogenized in guanidnium thiocyanate and the RNA is purified from the lysate by extraction with phenol:chloroform at reduced pH. Many samples can be processed simultaneously and speedily. The yield of total RNA depends on the tissue or cell source and is generally in the range of 4-7 µg/ml starting tissue or 5-10 µg/106 cells. IMPORTANT: Prepare all reagents used in this protocol with Diethyl pyrocarbonate (DEPC)-treated H2O. - [Read Purification of RNA from Cells and Tissues by Acid Phenol-Guanidinium Thiocyanate-Chloroform Extract]
This protocol is not phenol-based, but does require the addition of chloroform. The Concert Plant Reagent is intended for the isolation of RNA from a wide variety of plant tissues including blue spruce needles, potato tuber etc. - [Read Purification of RNA from Plant Tissue Using the Concert Plant Reagent]
Protocol for purification of synthetic oligonucleotides by polyacrylamide gel electrophoresis. As a rule of thumb, oligonucleotides >25 nucleotides should be purified by polyacrylamide gel electrophoresis, as should oligonucleotides of any length that yield anomalous results. After electrophoresis, the oligonucleotide is eluted from the gel and concentrated by reversed-phase chromatography on Sep-Pak C18 columns. - [Read Purification of Synthetic Oligonucleotides by Polyacrylamide Gel Electrophoresis Protocol]
Protocol for the recovery of a highly viable fraction for use in fertilization. Protocol uses an iodinated density gradient medium to adjust the density of the raw ejaculate to approx 1.170 g/ml by mixing with a high density medium (Ï >1.26 g/ml) and loading it beneath a discontinuous gradient. - [Read Purification of viable bovine spermatozoa of normal morphology.]
Protocol for random primer labeling of poly A and RNA. Includes: Random primer reaction; cDNA purification; Hybridization; Washing; Stripping of membranes. - [Read Random Primer Labeling of PolyA and RNA Protocol]
Rapid Elution of DNA Agarose Gels Protocol. This method allows quick purification of DNA fragments from agarose gels for use in cloning and other reactions. Higher yields of purified DNA can be obtained from commercially available purification kits, however greater ligation efficiencies per given amount of DNA have been seen with the use of these described spin columns. Hahn Lab. - [Read Rapid Elution of DNA Agarose Gels Protocol]
Protocol for the isolation of the lipid-rich microdomains of the plasma membrane, notably caveolae and lipid rafts. Methods for the isolation of lipid rafts are based on the insolubility of these structures in the nonionic detergent TritonX-100. Either the intact cells are treated with a detergent-containing solution or a post-nuclear supernatant is prepared from a cell homogenate and then Triton X-100 is added to this supernatant. - [Read S20 Purification of detergent-insoluble lipid rafts from cells and tissues.]
Protocol for screening immobilized dyes for their ability to bind a target protein. The selection of a dye adsorbent for the purification of the target protein is an empirical undertaking and is generally achieved by a trial-and-error approach. - [Read Screening Immobilized Dyes for their Ability to Bind a Target Protein Protocol]
Chromatography on oligo(dT) columns is the preferred method for large-scale purification (>25 µg) of poly(A)+ RNA extracted from mammalian cells. Typically, between 1% and 10% of the RNA applied to the oligo(dT) column is recovered as poly(A)+ RNA. Because the method can be frustratingly slow, it is not recommended for purification of poly(A)+ RNA from multiple samples. For this purpose, batch elution (Selection of Poly(A)+ RNA by Batch Chromatography) is the better choice. - [Read Selection of Poly(A)+ RNA by Oligo(dT)-Cellulose Chromatography - Subscription Required]
DNA microarrays are an ordered arrangement of DNA molecules complementary to genes of interest that are "spotted" by robotic equipment onto a glass slide substrate. The expression of genes in cells can be monitored with microarrays by preparing cDNA from the mRNA of cells of interest and measuring the hybridization to the microarray. This protocol describes the labeling of genomic DNA for use as a probe for hybridization to the cDNA spotted on the array.
This Microarray Protocol Preparation of Fluorescent DNA Probes from Human mRNA protocol describes the production of probes labeled with the fluorescent dyes, Cy3 and Cy5, following the synthesis of cDNA from human mRNA and the hybridization of the probes to DNA microarrays.
This protocol describes the electroporation of the BMH 81-17 mut S strain that is recommended for tranformation of the site directed mutagenesis of dsDNA (See Protocol on Site-Directed Mutagenesis on Double Stranded DNA). BMH 81-17 mut S are a mismatch repair defective (mut S) Escherichia coli strain. The probability that the two mutations will cosegregate during the first round of DNA replication is increased in this strain.