Rnai Library Screening
Rnai Library Screening - Related Videos
09:40
RNAi Screening to Identify Postembryonic Phenotypes in C. elegans
0 Views •
Cited by 9 •
2012
We describe a sensitized method to identify postembryonic regulators of protein expression and localization in C. elegans using an RNAi-based genomic screen and an integrated transgene that expresses a functional, fluorescently tagged protein.
15:31
MISSION esiRNA for RNAi Screening in Mammalian Cells
0 Views •
Cited by 17 •
2010
Here we use a human esiRNA library in a high-throughput screen for genes involved in cell division. We demonstrate how to set up and conduct an esiRNA screens, as well as how to analyze and validate the results.
16:05
Large-Scale Screens of Metagenomic Libraries
0 Views •
Cited by 9 •
2007
Metagenomic libraries archive large fragments of contiguous genomic sequences from microorganisms without requiring prior cultivation. Generating a ...
09:51
RNAi in C. elegans
0 Views •
2023
RNA interference (RNAi) is a widely used technique in which double stranded RNA is exogenously introduced into an organism, causing knockdown of a target gene. In the nematode, C. elegans, RNAi is particularly easy and effective because it can be delivered simply by feeding the worms bacteria that express double stranded RNA (dsRNA) that is complementary to a gene of interest. First, this video will introduce the concept of RNA interference and explain how it causes targeted gene knockdown.
09:12
MISSION LentiPlex Pooled shRNA Library Screening in Mammalian Cells
0 Views •
Cited by 11 •
2011
Here we use a human LentiPlex pooled library and traditional sequencing methods to identify gene targets promoting cell survival. We demonstrate how to set up and deconvolute a LentiPlex screen and validate the results.
FAQs
Both reagent types reduce expression of selected genes through sequence-guided RNA interference, but they represent distinct formats within the library. A screen can therefore compare gene-level effects across collections built from siRNAs or shRNAs. The important experimental outcome is whether reducing a particular transcript consistently changes survival, proliferation, or drug response in the chosen assay.
The assay determines which gene dependencies become detectable. Selection-based measurements can connect gene loss with continued survival or loss of viability, whereas imaging assays can capture cellular phenotypes linked to proliferation or treatment response. Choosing a readout that directly reflects the research question helps distinguish genes affecting the intended cancer phenotype from genes producing unrelated cellular changes.
A strong phenotype does not automatically prove that the intended gene caused the effect. Sequence-dependent off-target activity can alter cellular behavior independently of the nominated target, and assay conditions may influence whether a dependency or drug-response effect appears. Consequently, hit interpretation requires testing independent reagents directed at the same gene and examining whether the phenotype is reproducible.
Researchers expose cells to a collection of siRNA or shRNA reagents, apply a selection or imaging-based assay, and connect observed phenotypes to the targeted genes. Depending on the design, the readout may reflect survival, proliferation, or response to a drug. Candidate hits then move into validation experiments rather than being treated as confirmed findings immediately.
The approach is useful when researchers need to discover genes that cancer cells depend on or that influence response to treatment. Comparing phenotypes under relevant growth or drug conditions can reveal tumor dependencies, resistance mechanisms, and candidate therapeutic targets. These findings can guide follow-up studies aimed at determining whether a gene has a specific and actionable role.
Validation should use independent RNAi reagents targeting the same candidate gene to determine whether the phenotype persists across distinct sequences. Rescue experiments provide a complementary test by asking whether restoring the relevant gene reverses the observed effect. Agreement between these approaches strengthens confidence that the screen identified a specific gene-dependent phenotype rather than an off-target response.