Cre-loxp Recombination
Cre-loxp Recombination - Related Videos
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.
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.
05:19
Segmental Adeno-Cre Infection: A Technique to Generate Isolated Colorectal Cancer using Genetically Engineered Mouse Models
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2023
This video describes the generation of a colorectal mouse model by segmental adeno-cre infection. The infected colon segment leads to tumorigenesis within this segment of the mucosa, resulting in adenomas ultimately progressing to invasive and metastatic carcinoma. This model is an attractive platform for studies of cancer biology and preclinical therapeutic trials.
08:13
A Cre-Lox P Recombination Approach for the Detection of Cell Fusion In Vivo
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Cited by 11 •
2012
A method to track cell fusion in living organisms over time is described. The approach utilizes Cre-LoxP recombination to induce luciferase expression upon cell fusion. The luminescent signal generated can be detected in living organisms using biophotonic imaging systems with a sensitivity of detection of ˜1,000 cells in peripheral tissues.
FAQs
The relative orientation of paired loxP sites determines whether the intervening DNA is excised or inverted. Sites arranged in one orientation support removal of the sequence between them, whereas the opposite orientation supports reversal of that segment. This design principle allows researchers to choose whether an experiment deletes a genetic element or changes its orientation.
Cre recombinase provides the catalytic activity that recognizes paired loxP sites and drives DNA rearrangement between them. Because the reaction depends on the presence and arrangement of these specific sites, researchers can place recombination control within a selected genetic design. The resulting rearrangement changes the target sequence without requiring nonspecific genome-wide modification.
When loxP sites occur on separate DNA molecules, Cre-mediated recombination can support integration rather than only rearranging a sequence within one molecule. This expands the system beyond deletion or inversion and makes it useful for engineering genetic constructs. The arrangement of the target sites therefore influences both the type of rearrangement and the broader design of the experiment.
Researchers can organize the system so that recombination occurs in selected tissues or at a chosen time, allowing genetic changes to be studied with greater experimental precision. This control is especially important when a gene has different effects across cell types or developmental stages. It enables conditional rather than universally applied genetic changes in model organisms and engineered cells.
A conditional knockout design places loxP sites around the genetic sequence selected for later removal. Cre recombinase is then introduced or activated under conditions that restrict recombination to the intended tissue or time point. Once the paired sites recombine, the intervening sequence is excised, allowing researchers to examine gene function in a controlled biological context.
The system supports several outcomes besides conditional knockouts, including transgene activation, cell-lineage tracing, and construction of programmable genetic circuits. These applications use controlled DNA rearrangement to connect a genetic event with a measurable change in gene activity or cellular history. Consequently, the approach contributes to studies of gene function, cell behavior, model organisms, and synthetic biology.