Extreme care should be used to identify and verify positive reactions, however, because cross-reactions are common. Counterstaining is essential for examining worms by immunofluorescence and is used to identify the exact cell in which an antigen appears. Methods for counterstaining include labeling all cells with a fluorescent dye that is specific for nucleic acids (e.g., DAPI or propidium iodide) and using GFP driven by tissue-specific promoters. - [Read Antibody Addition and Detection for Staining Caenorhabditis elegans Protocol]
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]
Counterstains are used to help differentiate the various cell types of subcellular structures seen in cell staining. They are essential for tissue sections, allowing the identification of the cell types, but also may be helpful in other staining reactions. - [Read Counterstains Protocol]
Protocol used to study secretion of proteins and prostaglandins by endometrium from the cow, ewe, mare, bitch and other species. The technique is also useful for culture of peri-implantation conceptuses and placental tissues for metabolic labelling studies and to obtain conceptus secretory proteins for biological studies.The medium used is called Pig MEM, which is a modified minimum essential medium supplemented with non-essential amino acids, vitamins, insulin and additional glucose. - [Read Culture of Endometrial Explants and Peri-implantation Conceptuses to Monitor Synthesis and Secretion]
Cytostatic factor extract (CSF) preparation for spindle assembly protocol. Protocol includes tips such as: The quality of the eggs is essential for good CSF extracts. Always sacrifice quantity for quality when trying to make functional extracts. - [Read Cytostatic Factor (CSF) Extract Preparation for Spindle Assembly Protocol]
Protocol for cytostatic factor extract preparation for spindle assembly. The quality of the eggs is essential for good CSF extracts. Always sacrifice quantity for quality when trying to make functional extracts. Discard any batches of eggs that have "puff balls" or activated eggs that constitute more than 10% of the eggs. Use laid eggs and collect eggs at about 16 to 17 hours after priming with Progesterone (found in Pregnant Mare Serum Gonadotropin (PMSG)). - [Read Cytostatic Factor (CSF) Extract Preparation for Xenopus Spindle Assembly Protocol]
Article describe the preparation of cells for correlative electron microscopy after live light microscopic observation of fluorescently labeled cytoskeletal proteins microinjected into the same cells. Since identification of cytoskeletal elements in electron microscopic preparations is an essential part of any correlative study, procedures for immunogold labeling of cytoskeletal components and for myosin S1 decoration of actin filaments are also described. - [Read Electron Microscopy of the Cytoskeleton of Cultured Cells]
Protocol describes a method for performing isoelectric fractionation of a maize embryo sample using a multicompartment electrolyzer(MCE). This prefractionation of proteins having pIs within a certain pH interval is essential for allowing high loads of protein to be resolved on narrow and ultra-narrow immobilized pH gradients used in 2D electrophoresis. The isoelectric membranes in the MCE act like isoelectric traps capturing all the protein species having pIs encompassing the pI value of each... - [Read Fractionation of Maize Embryo Proteins for 2-D Gel Electrophoresis Using Multicompartment Electrolyz]
Using confocal laser-scanning microscope & GFP fusion proteins in time-lapse imaging to visualize the behavior of organelles and to track membrane-bound transport intermediates that bud off from organelles. Practical issues related to construction & expression of GFP fusion proteins are discussed. Essential for optimizing the brightness and expression levels of GFP fusion proteins so that intracellular membrane-bound structures containing these fusion proteins can be readily visualized. - [Read Imaging of Organelle Membrane Systems and Membrane Traffic in Living Cells]
Direct labeling of purified antibodies is the method of choice when simultaneously visualizing two or more antibodies of the same species, class, or subclass. This allows the localization of multiple antigens to be compared in the same cell, tissue, or sample. Labeled primary antibodies are also useful for improving background-to-readout ratios, and they can be essential for immunoassays in which good quantification is needed. - [Read Labeling Antibodies with Fluorochromes Protocol]
Media for Culture of Mammalian Cells Protocol- https://catalog.invitrogen.com/index.cfm?fuseaction=iProtocol.unitSectionTree&treeNodeID=9E662B6F09C1BB8FBC47FC2A7E61A8A3&objectid=66739B890A55AC13354418E67F28E693
The culture medium is an essential component of the in vitro environment and must be selected or designed with care. This protocol provides guidelines for design of serum-containing and serum-free media, selective and specialty media, and media for growth under special conditions such as soft-agar growth. - [Read Media for Culture of Mammalian Cells Protocol]
Cells incorporate 35S-methionine or cysteine during the protein synthesis. Thus it is essential to use Met,Cys-free medium and dialyzed FCS during the labeling. Short period of incubation with 35S-methionine or cysteine will result in radiolabeling (pulse), and additional incubation with excess concentration of unlabeled Met+Cys (chase) is needed for complex glycoproteins like integrins to get expressed as a maturated form. - [Read Metabolic Labeling & Immunoprecipitation Protocols]
Protocol describes a target selective S. aureus whole cell assay that combines agar-diffusion and protein over expression techniques. This agar based two-plate differential sensitivity assay was used to help confirm the newly discovered antibiotic platensimycin inhibited bacterial growth by specifically targeting the essential FASII enzyme FabF6. - [Read Target Specific Whole Cell Assay for Antibacterial Drug Discovery Protocol]
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.
This protocol a protocol on how to generate transfected embryonic stem (ES) cell clones. The previous protocol in this series is the Protocol for Electroporation of ES cells. The next protocol in the series is the Protocol on Disaggregation, Expansion, and Freezing of Transfected ES Clones.