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 describes how subcellular-sized particles are accelerated to high velocity to carry double-stranded RNA (dsRNA) into Drosophila embryos. The major advantage of this procedure over microinjection (Microinjection of dsRNA into Drosophila Embryos) is that particle bombardment is easier and faster to perform. In addition, the mechanical trauma received is far less than by microinjection, allowing better survival of embryos and fewer phenotypic artifacts. - [Read Delivery of dsRNA into Drosophila Embryos by Gene Gun Protocol]
Protocols for gene expression and protein localization in Arabidopsis. Includes: Detection of the native protein; Detection of a recombinant version; Immunofluorescence detection in Arabidopsis protoplasts; Isolation of Arabidopsis seedling protoplasts; Subcellular localization of GUS-fusion proteins in Arabidopsis seedlings; Localization of Arabidopsis proteins with GUS in situ enzyme assay. - [Read Gene Expression and Protein Localization in Arabidopsis Protocols]
It is desirable to prepare subcellular fractions, either to localize proteins or to improve the sensitivity of protein detection. This procedure describes the enrichment of chloroplasts from Arabidopsis. - [Read Preparation of Arabidopsis Chloroplasts Protocol]
It is often desirable to prepare subcellular fractions, either to localize proteins or to improve the sensitivity of protein detection. This procedure describes the enrichment of mitochondria from Arabidopsis. - [Read Preparation of Arabidopsis Mitochondria Protocol]
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]
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]
GUS is used as a tag to address nuclear localization whereas GFP is more versatile. GFP is detectable directly in living cells, GUS is only detected indirectly by staining of fixed tissue which may lead to artifacts or may obscure problems with protein solubility. In this protocol, protein localization is routinely assayed after particle-mediated transient transformation of onion epidermal cells. With this method it can be determined rapidly whether a given fusion protein is active and.... - [Read Subcellular Localization of GUS- and GFP-Tagged Proteins in Onion Epidermal Cells]
Small ubiquitin-like modifier (SUMO) is a small molecule, but has a variety of regulatory functions in cells. SUMO modification is involved in transcriptional regulation, subcellular localization, and protein-protein interactions. SUMO conjugation requires sequential E1-dependent activation, E2-dependent conjugation, and E3-dependent ligation steps. Protocol includes: In vivo and in vitro SUMOylation assay and deSUMOylation assay. - [Read Sumoylation and Desumoylation Assays for a Chromatin-Remodelling Complex In Vivo and In Vitro]
Tissue subcellular fractionation and protein extraction for use in mass-spectrometry-based proteomics. Although many methods exist for fractionating proteins, the method described here can capture the majority of subcellular fractions simultaneously at reasonable purity. The scalability of this method makes it amenable to small samples, such as embryonic tissues, in addition to larger tissues. The protocol described is for the general fractionation and extraction of proteins from organs / tissue - [Read Tissue subcellular fractionation and protein extraction for use in mass-spectrometry-based proteomic]
Several methods have been developed to "retrieve" antigens that have been masked by fixation. The principle behind using the microwave oven method described here is to use extended periods of heat to break some of the subcellular structures that block antibody access. Be aware that any of the antigen retrieval methods should be avoided wherever possible, because they may introduce artifactual false-positive staining. - [Read Unmasking Hidden Epitopes Using the Microwave Oven Protocol]
The principle behind the pressure cooker method described here is to use extended periods of heat to break some of the subcellular structures that block antibody access. This approach is appropriate for handling specimens on glass slides. The major advantages of the pressure cooker method are the ability to handle a large number of slides simultaneously, the convenience of using metal racks, and the avoidance of any hot spots that are found in the microwave. - [Read Unmasking Hidden Epitopes Using the Pressure Cooker Protocol]