Many replacement vectors (e.g., the EMBL series, {lambda}2001, and {lambda}DASH) contain a series of restriction sites, arranged in opposite orientations, at each end of the central stuffer fragment. Digestion of these vectors with two different restriction enzymes yields left and right arms, a stuffer fragment, and short segments of the polycloning sites. These can easily be removed from the arms by differential precipitation with isopropanol or spun-column chromatography. - [Read Preparation of Bacteriophage lambda DNA Cleaved with Two Restriction Enzymes Protocol]
A procedure for direct and indirect staining of single-cell suspensions of lymphoid tissue or peripheral blood lymphocytes to detect cell surface membrane antigens is presented. In addition, support protocols present methods for fluorescence labeling of purified antibodies. A protocol for flow cytometric analysis of intracellular antigens in single-cell suspensions is also included. - [Read Preparation of Cells and Reagents for Flow Cytometry Protocols]
An ideal method of tissue preparation ensures both good specimen morphology and that the target molecules are in the optimum state for probe access and hybridization. DNA:DNA in situ hybridization is usually carried out on chromosome spread preparations where chromosome and nuclei are released from cells and spread on a glass microscope slide. This method yields well separated and enlarged chromosomes with good morphology which can be analyzed in transmitted light or fluorescence microscopes. - [Read Preparation of Chromosome Spreads]
The employment of differential centrifugation to prepare crude fractions of subcellular particles from homogenates is often a necessary first step to a subsequent purification of one or more particles on a density gradient. This protocol describes the use of differential centrifugation to fractionate a mammalian liver
homogenate but similar methods should be applicable to all mammalian tissues and cultured cells. - [Read Preparation of Crude Subcellular Fractions by Differential Centrifugation Protocol]
Protocol for preparation of denaturing polyacrylamide gels containing formamide.The inclusion of formamide in sequencing gels eliminates secondary structure in the DNA during electrophoresis. Formamide gels are particularly useful and almost a necessity when sequencing DNA templates with a G/C content >55%. - [Read Preparation of Denaturing Polyacrylamide Gels Containing Formamide Protocol]
This protocol describes the preparation of concatamerized oligonucleotides and their coupling to cyanogen-bromide-activated Sepharose. The procedure uses a commercially activated resin, which can be purchased as a lyophilized powder. Keith Brocklehurst et al. - [Read Preparation of DNA Affinity Resin - Subscription Required]
Protocol for preparation of DNA for pulsed-field gel electrophoresis: isolation of DNA from mammalian cells and tissues. Genomic DNAs from mammalian cells are prepared for pulsed-field gel electrophoresis by lysing cells in situ in an agarose plug. Following digestion with an appropriate restriction enzyme, the plug is loaded directly into the well of a pulsed-field gel or it can be melted before loading. - [Read Preparation of DNA for Pulsed-field Gel Electrophoresis: Isolation of DNA from Mammalian Cells]
Protocol for preparation of DNA for pulsed-field gel electrophoresis: isolation of intact DNA from yeast. Yeast cells are first treated enzymatically to break down the cell walls and then resuspended in low-melting-temperature agarose plugs. The DNA is liberated by infusing the plugs with lysis buffer and proteases. This method is used to prepare both conventional and artificial yeast chromosomes. - [Read Preparation of DNA for Pulsed-field Gel Electrophoresis: Isolation of Intact DNA from Yeast]
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.
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.
A protocol for the selection of Phage Antibodies using Immobilized Antigen. This method describes the selection of antibodies from bacteriophage antibody libraries that recognize a specific antigen. The phage display library of antibody-displaying phage particles is exposed to antigen attached to a solid substrate (Nunc Immuno™ tubes). The phage particles with affinity for antigen bind to the immobilized antigen and are selected from the library of phage expressing antibodies.