occurs Protocols

Category: Cytogenetics Protocols

This CGH Protocol is used for DNA of good quality when available in sufficient amounts. We usually do replicate hybridizations using samples labeled "inversely" (reversing the label for test and normal DNA's). If appreciable artifact occurs, then alternative labels are tried. - [Read CGH of Direct Labeled Test DNA vs Normal DNA Protocol]

Category: Stem Cell Protocols: Stem Cell Culture Protocols

In vitro differentiation of ES cells occurs when the cells are allowed to aggregate in suspension culture in the absence of mouse embryonic fibroblast (MEF) feeders and leukemia inhibitory factor (LIF). Hanging drops provide a uniform aggregate size, which is then expanded by continued growth in suspension culture. The embryoid bodies are then plated and allowed to differentiate further in culture. - [Read Differentiation of Embryonic Stem (ES) Cells Using the Hanging Drop Method]

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: In Vitro Reconstitution Protocols

Protocol outlines the general procedure and requirements for in vitro translation of CFTR and outlines some assays using in vitro translated product. Core glycosylation of CFTR occurs in the ER. An assay for this processing step requires the addition of microsomal membranes to the basic in vitro translation mixture. This protocol takes this into account. - [Read In vitro Translation Assays for CFTR]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols: Cell Cycle Analysis Protocols

Exponentially growing cells are asynchronous with respect to the cell cycle stage. Detection of cell cycle-related events is improved by enriching the culture for cells at the stage during which the particular event occurs. Methods for synchronizing cells are provided here, including those based on morphological features of the cell. - [Read Methods for Synchronizing Cells at Specific Stages of the Cell Cycle]

Category: Cell Biology and Cell Culture: In Vitro Reconstitution Protocols

In this protocol nuclei isolated from cells expressing the gene of interest are incubated with radiolabeled UTP which is incorporated into nascent RNA transcripts by RNA polymerase molecules that were actively transcribing at the time the cells were harvested. Because very little denovo initiation of RNA synthesis occurs in isolated nuclei, transcription of the target gene can be measured by hybridizing the radiolabeled RNA to an excess of the target gene immobilized on a nitrocellulose or nylon - [Read Protocol for Transcriptional Run- On Assays]

Category: Nucleic Acid Detection Protocols: Nucleic Acid Blotting Protocols

Protocol for southern blotting: simultaneous transfer of DNA from a single agarose gel to two membranes. DNA can be simultaneously transferred from opposite sides of a single agarose gel to two membranes.  Bidirectional transfer occurs rapidly at first, but soon slows down as the gel becomes dehydrated.  Because the efficiency of transfer is low, the method works best when the target sequences are present in high concentration - [Read Southern Blotting: Simultaneous Transfer of DNA from a Single Agarose Gel to Two Membranes Protocol]