molecules Protocols

Category: DNA Microarray Protocols

This protocol describes the labeling of eukaryotic RNA with aminoallyl labeled nucleotides via first strand cDNA synthesis followed by a coupling of the aminoallyl groups to either Cyanine 3 or 5 (Cy 3/Cy5) fluorescent molecules. Hasseman. TIGR Microarr - [Read Amino-allyl Labeling]

Category: Cloning Protocols

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]

Category: Cell Biology and Cell Culture

Protocol for automated imaging-based high-throughput screening for small molecules that reverse cellular senescence. - [Read Automated Imaging-Based High-Throughput Screening: Small Molecules that Reverse Cellular Senescence]

Category: Neuroscience Protocols

Bead aggregation assay to demonstrate presynaptic differentiation induced by the NGL family of cell adhesion molecules. - [Read Bead Aggregation Assay Protocol]

Category: PCR Protocols: PCR Cloning Protocols

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]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols

Protocol for estimating the number of CD38 molecules on the CD8+ T lymphocytes of HIV-infected individuals. Includes: RECOMMENDATION OF VENDOR FOR PE-CD38 AND PE-CD4; VALIDATION OF LOGARITHMIC AMPLIFIER LINEARITY AND SENSITIVITY; CONSERVATION OF THE LEVEL OF CD4 ANTIGEN EXPRESSION ON CD4+ LYMPHOCYTES AND ITS USE AS A BIOLOGIC STANDARD FOR FLOW CYTOMETER INSTRUMENT CHARACTERIZATION; DETERMINATION OF THE NUMBER OF CD38 MOLECULES PER CD8+ CELL; etc.. - [Read Estimating the Number of CD38 Molecules on the CD8+ T Lymphocytes of HIV-Infected Individuals]

Category: Cell Culture Protocols: Cell Fixing Protocols

Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. Commercial formaldehyde solutions are not recommended, because they lack the advantages of using a variable-length polymer, and the cells will simultaneously be fixed with the alcohol (usually methanol). - [Read Fixing Attached Cells in Paraformaldehyde Protocol]

Category: Cell Culture Protocols: Cell Fixing Protocols

Treating cells with paraformaldehyde leads to the establishment of chemical cross-links between free amino groups. When the cross-links join different molecules, a latticework of interactions occurs that holds the overall architecture of the cell together. - [Read Fixing Suspension Cells with Paraformaldehyde Protocol]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols: Cell Sorting Protocols

Flow cytometry is a widely used method for characterizing and separating individual cells. This basic protocol focuses on: measure fluorescence intensity produced by fluorescent-labled antibodies and ligands that bind specific cell-associated molecules. Includes: Immunofluorescence Staining and Flow Cytometry Analysis. - [Read Flow Cytometry Analysis Protocol]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols

Flow cytometry is a widely used method for characterizing and separating individual cells. This basic protocol focuses on: measure fluorescence intensity produced by fluorescent-labled antibodies and ligands that bind specific cell-associated molecules. Includes: Immunofluorescence Staining; Flow Cytometry Analysis. - [Read Flow Cytometry Analysis Protocol]

Category: Microscopy Protocols: Fluorescence Microscopy Protocols

Most biological specimens are relatively transparent, so details of internal and intracellular morphology are difficult to image in untreated living specimens using simple bright-field techniques. Fluorescence microscopy offers greater advantages and possibilities for increasing contrast and determining the specific localization of molecules in cells. Article outlines the three methods most commonly used to introduce an appropriate label into Drosophila tissue without perturbing the process. - [Read Fluorescent Reagents for Live Cell Imaging and Their Introduction into Cells]

Category: Microscopy Protocols

The atomic force microscope (AFM) is one of the most powerful tools for determining the surface topography of native biomolecules at subnanometer resolution. The AFM can also provide insight into the binding properties of biological systems. In order to determine the specific interaction between two kinds of molecules (e.g., avidin and biotin). Includes information on principle of AFM and application of AFM. - [Read Imaging, Measuring and Manipulating Native Biomolecular Systems with the Atomic Force Microscope]

Category: Immunology: Immunofluorescence Protocols: Immunofluorescence Staining Protocols

Provides a protocol for indirect immunofluorescence, which is a method that provides information about the locations of specific molecules and the structure of the cell. Antibody molecules for a specific target molecule are exposed to the cell or tissue being investigated. The binding of these molecules is detected by incubating the sample with a secondary antibody specific for immunoglobulin molecules and conjugated to fluorophore. - [Read Immunofluorescence Staining Protocol]

Category: Immunology: Immunoprecipitation Protocols

Protocol for immunoprecipitation of mRNA-protein complexes. In this protocol, an antibody targeting an RBP of interest is used to immunoprecipitate the RBP and any interacting molecules from a cell lysate. Reverse transcription followed by PCR is then used to identify individual mRNAs isolated with the RBP. This method focuses on examining an association between a specific RBP-mRNA complex, and it is best suited for a small scale screening of known or putative binding partners. - [Read Immunoprecipitation of mRNA-Protein Complexes Protocol]

Category: Molecular Biology Protocols: Carbohydrate Protocols

Immunostaining thin layer chromatograms TLC is a very sensitive detection technique of functionally active carbohydrate ligands of protein receptors. Carbohydrate structures are detected in glycolipids from complex mixtures of molecules extracted from the relevant target tissue. Proteins analyzed can be antibodies, chimeric Ig proteins, selectins, lectins, toxins, and other carbohydrate binding proteins. John L. Magnani~GlycoTech Corporation, Rockville, Maryland - [Read Immunostaining Thin Layer Chromatograms Of Glycolipids]

Category: Avian Bird Protocols

Protocol describes a method for in ovo transfection of avian embryos with double-stranded RNA (dsRNA). The dsRNA is injected into the spinal cord of the embryo. Subsequent electroporation facilitates the cellular uptake of the dsRNA molecules. - [Read Injection of dsRNA and Electroporation in Avian Embryos Protocol]

Category: RNAi Technology Protocols: RNAi Avian Embryos Protocols

Protocol describes a method for in ovo transfection of avian embryos with double-stranded RNA (dsRNA).  The dsRNA is injected into the spinal cord of the embryo.  Subsequent electroporation facilitates the cellular uptake of the dsRNA molecules.  It may be necessary to optimize the stage of the embryo and the electroporation procedure to improve the effectiveness of in ovo RNAi—cell competence changes with differentiation. - [Read Injection of dsRNA and Electroporation in Avian Embryos Protocol]

Category: Signalling Signal Transduction Protocols: Cytokine Protocols

Intracellular Cytokine Staining Protocol. Analysis of surface molecules and intracellular cytokines at the single-cell level using FACS or flow cytometry. - [Read Intracellular Staining for Flow Cytometric Analysis Protocols]

Category: Microscopy Protocols: Fluorescence Microscopy Protocols

Article presents an introduction to fluorescence microscopy. Includes: Fundamentals of Excitation and Emission; Stokes' Shift; Fading, Quenching, and Photobleaching; Fluorescence Light Sources; Filter Terminology; The Fluorescence Light Budget; Detecting Single Molecules. - [Read Introduction to Fluorescence Microscopy]

Category: Immunology: Mononuclear Cell Isolation Protocols: B Lymphocyte Isolation Protocols

A flow cytometry technique is presented, which results in the selection and isolation of two populations of cells from a complex mixture based on physical properties (e.g., size and internal granularity) and correlated expression of several surface molecules - [Read Isolation of Ly-1+/CD5+ B Cells by Cell Sorting Protocol]

Category: Microscopy Protocols: Confocal Microscopy Protocols

Protocol describes the acquisition and processing of confocal fluorescent and bright field images of live cells, expressing cyan fluorescent protein(CFP) and/or yellow fluorescent protein (YFP), with a spinning disk confocal head on a Zeiss Axiovert 200 M microscope. This procedure is used to help determine if N- or Cterminal tagging of signaling molecules alters the steady state localization pattern of the signaling protein in question. - [Read Live Cell Spinning Disk Confocal Fluore Imaging of Cells- Colocalization of Fluorescent Protein Tags]

Category: Cell Biology and Cell Culture: Cell Adhesion Protocols

Many proteins and molecules promote cell adhesion including several cell surface carbohydrate binding proteins. Cell adhesion measurements on 96-well microtiter plate format are difficult due to the shear forces generated by washing the wells. The protocol here introduces the use of a liquid-filled wash chamber that separates unbound cells by gravity. This eliminates uncontrolled shear forces and passage of adherent cells through a liquid/air interface. John L. Magnani~GlycoTech Corporation. - [Read Measurement of Cell Adhesion Under Static Conditions]

Category: Bacterial Protocols

Ice tea has a complex composition, which leads to reduced filterability, and a decrease in sample throughput. Its composition can generate background or false positive signals. It is also well known that ice tea contains molecules that can inhibit the bioluminescence reaction, which can generate false negative results. The aim of this study was to develop a protocol that was able to neutralize these affects and enable faster detection of contamination. - [Read Microbial Detection in Ice Tea Using the Millipore Milliflex Rapid Microbiology Detection System]

Category: Cell Biology and Cell Culture: Cell Viability Protocols

The latest generation of Promega cell-based assays includes luminescent and fluorescent chemistries to measure markers of cell viability, cytotoxicity and apoptosis, as well as to perform reporter analysis. Using these tools researchers can investigate how cells respond to growth factors, cytokines, hormones, mitogens, radiation, effectors, compound libraries and other signaling molecules. The protocols provided are guidelines for multiplexing cell-based assays & are intended as starting points. - [Read Multiplexing Cell Viability Assays Protocols]

Category: Microscopy Protocols: Live-Cell Imaging Protocols

This protocol describes a method for observing and measuring the movement of RNA molecules in the nucleus of living mammalian cells. Caged fluorescein-labeled DNA oligonucleotides are introduced into living mammalian cells, where they demonstrably hybridize to complementary RNA. After site-specific photoactivation at desired sites within the cell, the RNA movements away from those sites are followed and digitally recorded using a rapid acquisition microscopy system. - [Read Photoactivation-Based Labeling and In Vivo Tracking of RNA Molecules in the Nucleus]