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]
The procedure is to mutagenize a large population of worms with trimethylpsoralen and UV irradiation, set up 1152 subpopulations, screen DNA made from this library for deletions in specific genes by nested PCR, and then to recover single worms carrying the deletions through a sib-selection process. - [Read C. elegans Gene Knockout Protocol]
Protocol for C. elegans RNAi. Includes: Transformation of competent cells; Blunt-end ligation; Preparation of competent cells; Dephosphorylation of linear plasmid DNA; Restriction Digest: EcoRV; Insert amplification from gDNA; Gel purification: QiaQuick gel purification kit; Mini-prep; Transformant Screening; Bacterial preparation and induction; Preparation of worms for RNAi feeding. - [Read C. elegans RNAi Protocol]
The cosuppression effect in C. elegans does not spread throughout the animal. Cosuppression in C. elegans can be triggered by highly repetitive transgenes that contain gene constructs. - [Read Cosuppression in C. elegans Protocol]
Cosuppression is a process in Caenorhabditis elegans that closely resembles RNAi. In contrast to RNAi, however, the cosuppression effect in C. elegans does not spread throughout the animal. Cosuppression in C. elegans can be triggered by highly repetitive transgenes that contain gene constructs. - [Read Cosuppression in C. elegans Protocol]
Protocol uses Rnase protection to detect short interfering RNAs (siRNAs) in RNA preparations from Caenorhabditis elegans. SiRNAs can also be detected by northern blot. However, the Rnase protection assay seems to be more sensitive. - [Read Detection of siRNA in C. elegans Using Rnase Protection Protocol]
Protocol for fixation and permeabilization of C. elegans. Protocol works for all stages except dauers (which won't open) and hypoclorite-treated eggs (which disintegrate). Luckily, hypochlorite treatment and fixation are by themselves sufficient to open eggs. - [Read Fixation and Permeabilization of C. elegans Protocol]
Bouin’s fixative is a particularly good choice for worms because it penetrates dense tissues well and is extremely good for fixing antigens. Like all strong fixatives, however, it is unsuitable for some antibody-antigen pairs. In such cases, the length of time in the Bouin’s fixative can be shortened, or paraformaldehyde fixation can be used instead. - [Read Fixing Caenorhabditis elegans in Bouin’s Fixative Protocol]
Common method for fixing worms is to use paraformaldehyde. This method provides a gentler fixation than the Bouin’s method, but often requires the use of collagenase. This method is particularly good for examining adult worms. - [Read Fixing Caenorhabditis elegans in Paraformaldehyde Protocol]