problem Protocols

Category: DNA Protocols: Cosmid Library Protocols

Amplification of cosmid libraries may result in distorted representation of cloned genomic sequences and should be avoided wherever possible. In this method of amplification, distortion of the library is rarely a problem because at no stage are bacteria containing different recombinant cosmids grown in competition with one another. - [Read Amplification and Storage of a Cosmid Library: Amplification on Filters Protocol]

Category: Reporter Gene Assays: B-Galactosidase Assay Protocols

This assay is used when working with phage vectors carrying the beta-gal gene. If the cloning event disrupts a normally functional copy of the gene in the vector the resulting plaques would appear clear in the assay. If the phages contain a functional beta-gal gene they will form blue rings around their plaques. Any strain which is not an overproducer of beta-gal will work as indicator host bacteria; a single chromosomal copy of the gene is not a problem. - [Read Assay for Phage Containing the Beta-galactosidase Gene]

Category: Cell Biology and Cell Culture: Cell Culture Techniques: Cell Line Preservation Freezing

Advantages of Freezing Cell Cultures, Practical Aspects of Cell Freezing, Cryoprotection, Storage Vessels, Labeling and Recordkeeping, Recovery, Managing a Cell Repository, cell selection, Problem Solving Suggestions. Corning. by John A. Ryan - [Read General Guide for Cryogenically Storing Animal Cell Cultures]

Category: Cell Biology and Cell Culture: Troubleshooting Cell Culture Problems

Guide For Identifying And Correcting Common Cell Growth Problems. Corning. Surface Treatment Process, Problems Related to Technique, Problems Related to Incubators, Problems Related to Culture Media, Problem Solving Suggestions. - [Read Guide For Identifying And Correcting Common Cell Growth Problems]

Category: Immunohistochemistry Protocols

Immunohistochemistry trouble shooting guide. Includes problem, possible cause and solution. - [Read Immunohistochemistry Trouble Shooting Guide]

Category: Protein Protocols: Immunoprecipitation Protocols: Immunoprecipitation Troubleshooting

Immunoprecipitation Troubleshooting Guide. Stressgen. Problem: Non-specific background, Specific Background, Specific antigen not detected. With Solutions to common IP problems. - [Read Immunoprecipitation Troubleshooting Guide PDF]

Category: Plant Biology Protocols: Plant DNA RNA Isolation Protocols

A. thaliana has a very small haploid genome and this makes obtaining DNA somewhat difficult. The most notable problem is that DNA is usually contaminated with polysaccharide which inhibit restriction enzymes as well as other DNA modifying enzymes. This problem is most easily solved by using young plants which have not accumulated as much polysaccharide as older plants. The best results are obtained with plants that are two to three weeks post germinated. - [Read Plant DNA Extraction Protocol]

Category: Cytogenetics Protocols: In Situ Hybridization Protocols

This protocol fixes and prepares embryos for in situ hybridization to visualize transcript expression patterns. It is a modification of the method developed by Tautz and Pfeifle for whole-mount in situ analysis of embryos. Use of the standard hybridization protocol on RNAi-treated embryos results in high background staining, which makes visualization of transcript expression patterns practically impossible. The following modifications eliminate this problem and allow visualization of transcript. - [Read Transcript In Situ Hybridization of Whole-Mount Embryos for Phenotype Analysis of RNAi-Treated]

Category: Protein Protocols: Western Blot Protocol: Troubleshooting Western Blots

Problem: Poor Transfer, Problem: Poor Transfer. R&D Systems. - [Read Troubleshooting Guide: Western Blot]

Category: Cell Culture Protocols: Cell Culture Contamination Prevention and Removal Protocols

No cell culture problem is as universal as that of culture loss due to contamination. All cell culture laboratories and cell culture workers have experienced it. Culture contaminants may be biological or chemical, seen or unseen, destructive or seemingly benign, but in all cases they adversely affect both the use of your cell cultures and the quality of your research. Contamination problems can be divided into three classes: Minor annoyances, Serious problems, Major catastrophes. - [Read Understanding and Managing Cell Culture Contamination Protocol]

Category: Western Blot Protocols

Procedure describes how it denatures most of the modification and degradation proteins immediately giving the most accurate read out of the true levels of protein at the time of harvest.  However, in cases where detection is a problem, a limited purification (e.g. isolation of nuclear extract for the detection of transcription factors) might be required to allow analysis. - [Read Western Blot Analysis of Endogenous Gene Expression Protocol]