How the Cre-LoxP System Works | A Guide to Mouse Genetics Tools

In this video, we dive deep into the Cre-LoxP recombinase system, one of the most powerful tools in mouse genetics. 🧬 We break down: ✅ How Cre recombinase works ✅ The concept of floxed alleles and DNA recombination ✅ The different types of Cre lines—tissue-specific and inducible Cre systems ✅ How to generate null animals for knockout studies ✅ Useful resources for finding floxed alleles and Cre lines By the end of this video, you'll have a clear understanding of how Cre recombinase helps researchers dissect gene function in specific tissues and at specific time points—an essential approach for modern biomedical research. Resources mentioned: 🖥 Mouse Genome Informatics (MGI): https://www.informatics.jax.org/ 🖥 Jackson Laboratory (JAX): https://www.jax.org/ If you found this helpful, consider subscribing to the channel for more content on mouse genetics and colony management! 📌 Chapters (with Key Concept Highlights): Intro — What Are Recombinase Systems? Overview of recombinase systems in mouse genetics Focus on the Cre-LoxP system How the Cre-LoxP System Works Cre recombinase and LoxP sites Mechanism of gene deletion or flipping Introduction to floxed alleles and directionality Mention of Flp recombinase and Rainbow Mice Tissue-Specific Cre Recombinases Restricting Cre expression spatially How promoters drive tissue-specific expression Random insertion vs. targeted knock-in (KI) approaches Importance of heterozygosity in random transgenic lines Inducible Cre Systems (ERT2-Cre) Temporal control of recombination ERT2-Cre fusion proteins and how they work Combining tissue-specific and inducible systems Rosa26 locus overview Generating Null Animals (Full Knockouts) Importance of full gene knockout Breeding strategies and chimera generation Germline Cre recombinases (CMV-Cre, embryonic expression) Best Resources for Cre and Floxed Alleles Mouse Genome Informatics (MGI) Jackson Laboratory (JAX) resources Outro — Wrapping Up the Cre-LoxP System Recap of key concepts Encouragement to explore more mouse genetics content Chapters 00:00 Intro 00:39 Cre-LoxP basics 01:30 Cre-induced deletions 03:23 Flipping 05:00 Different Lox types 09:20 Transgenic Cres 10:38 Knock-In Cres 12:48 Rosa26 12:23 ERT2-Cre 14:52 Tamoxifen 16:44 Generating Null alleles 18:32 Germ line Cres 20:20 MGI website 20:42 Jax website 21:23 Recap 21:35 Outro 21:46 Other resources