Cre-based Systems
Cre-based Systems - Related Videos
03:12
CreER-LoxP System-Based Target Gene Inactivation: A Tamoxifen-Inducible Cre Recombinase System for Target Gene Knockout in a Mouse Model
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2025
This video describes a procedure for target gene knockout using a tamoxifen-inducible Cre-recombinase system following intraperitoneal injection of tamoxifen in a mouse model.
02:45
Assessment of Viral Fusion Inhibitors Using a Cre-Inducible Fluorescent Reporter
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2026
Source: Esposito, A. M.,et al. High-throughput Cre-Lox Activated Viral Membrane Fusion Assay to Identify Inhibitors of HIV-1 Viral Membrane Fusion. J. Vis. Exp. (2018)This video demonstrates a co-culture fluorescent assay to monitor cell-to-cell viral transmission. The assay uses a red-to-green reporter cassette to visualize viral membrane fusion and evaluate the efficacy of test compounds in blocking viral entry.
08:19
Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster
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Cited by 13 •
2011
Phenotypic variation for traits can result from mutations in cis-regulatory element (CRE) sequences that control gene expression patterns. Methods derived for use in Drosophila melanogaster can quantitatively compare the levels of spatial and temporal patterns of gene expression mediated by modified or naturally occurring CRE variants.
10:29
Inducing Cre-lox Recombination in Mouse Cerebral Cortex Through In Utero Electroporation
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Cited by 6 •
2017
Cell-autonomous functions of genes in the brain can be studied by inducing loss or gain of function in sparse populations of cells. Here, we describe in utero electroporation to deliver Cre recombinase into sparse populations of developing cortical neurons with floxed genes to cause loss of function in vivo.
01:59
Cre-LoxP Mediated Induction of Cerebral Cavernous Malformations in a Mouse Model
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2025
In this video, a genetically modified mouse pup carrying the Ccm2 gene flanked by loxP sites and Cre recombinase fused to an estrogen receptor is used to induce cerebral cavernous malformations (CCMs). The administration of 4-hydroxytamoxifen activates Cre in endothelial cells, leading to the deletion of Ccm2 and the formation of CCMs in the brain.
FAQs
The placement and orientation of loxP sites determine the kind of DNA rearrangement produced after Cre acts. Depending on that arrangement, the targeted sequence can be excised, inverted, or undergo another rearrangement. This makes loxP-site design central to experimental interpretation: the same recombinase can support different genetic outcomes, allowing investigators to tailor a system to the question being tested.
Spatial control limits Cre activity to a defined tissue or cell population, while temporal control restricts activity to a chosen developmental stage. Combining these dimensions helps distinguish where and when a gene or reporter produces an effect. In developmental studies, that separation is important because gene function, cell fate decisions, and tissue organization can change as tissues form.
Conditional deletion tests what happens when a gene is removed from selected cells, providing evidence about that gene’s role during development. Reporter activation instead identifies cells in which the system has acted, allowing researchers to follow their distribution or lineage as tissues form. Using both approaches can connect gene function with the behavior and fate of relevant cell populations.
Researchers first place loxP sites around the DNA sequence whose behavior they want to control. They then use a Cre source with tissue-specific or inducible expression, depending on the required location and developmental timing. After recombination, they examine the resulting gene change, reporter activity, or cell distribution to connect the engineered event with tissue development.
These systems are especially useful when researchers need to relate a genetic change to a defined cell population or developmental stage. They can conditionally remove a gene during tissue formation, activate a reporter in selected cells, or follow those cells as development proceeds. Such applications help investigate gene function, cell fate decisions, and mechanisms of tissue organization.
A change after conditional gene deletion can provide evidence about gene function in selected cells, whereas reporter activation can identify and track those cells as tissues form. Together, these readouts connect a targeted genetic manipulation with developmental outcomes such as cell fate decisions and tissue organization. The approach therefore links molecular events to changes occurring within defined populations over time.