Cairo University 3 articles published in JoVE Genetics Use of Freeze-thawed Embryos for High-efficiency Production of Genetically Modified Mice Hirofumi Nishizono*1,2,3, Mohamed Darwish*4,5, Hideki Uosaki6,7, Nanami Masuyama8,9,10, Motoaki Seki8,11, Hiroyuki Abe3, Nozomu Yachie8,9,10,12,13, Ryohei Yasuda1 1Max Planck Florida Institute for Neuroscience, 2Life Science Research Center, University of Toyama, 3Department of Biochemical Engineering, Graduate School of Science and Engineering, Yamagata University, 4Graduate School of Innovative Life Science, University of Toyama, 5Department of Biochemistry, Faculty of Pharmacy, Cairo University, 6Division of Regenerative Medicine, Center for Molecular Medicine, Jichi Medical University, 7Division of Stem Cell Research and Drug Development, Center for Development of Advanced Medical Technology, Jichi Medical University, 8Synthetic Biology Division, Research Center for Advanced Science and Technology, University of Tokyo, 9Institute for Advanced Biosciences, Keio University, 10Graduate School of Media and Governance, Keio University, 11Department of Molecular Oncology, Graduate School of Medicine, Chiba University, 12Department of Biological Sciences, School of Science, University of Tokyo, 13College of Arts and Sciences, University of Tokyo Here, we present a modified method for cryopreservation of one-cell embryos as well as a protocol that couples the use of freeze-thawed embryos and electroporation for the efficient generation of genetically modified mice. Genetics Microinjection of CRISPR/Cas9 Protein into Channel Catfish, Ictalurus punctatus, Embryos for Gene Editing Ahmed Elaswad*1,2, Karim Khalil*1,3, David Cline1, Patrick Page-McCaw4, Wenbiao Chen4, Maximilian Michel5, Roger Cone5, Rex Dunham1 1School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, 2Department of Animal Wealth Development, Faculty of Veterinary Medicine, Suez Canal University, 3Anatomy and Embryology Department, Faculty of Veterinary Medicine, Cairo University, 4Department of Molecular Physiology and Biophysics, Vanderbilt University, 5Life Science Institute, University of Michigan A simple and efficient microinjection protocol for gene editing in channel catfish embryos using the CRISPR/Cas9 system is presented. In this protocol, guide RNAs and Cas9 protein were microinjected into the yolk of one-cell embryos. This protocol has been validated by knocking out two channel catfish immune-related genes. Biochemistry A Simple Fractionated Extraction Method for the Comprehensive Analysis of Metabolites, Lipids, and Proteins from a Single Sample Mohamed Salem1,2, Michal Bernach1, Krzysztof Bajdzienko1, Patrick Giavalisco1 1Max Planck Institute of Molecular Plant Physiology, Golm, Germany, 2Department of Pharmacognosy, Faculty of Pharmacy, Cairo University A protocol for comprehensive extraction of lipids, metabolites and proteins from biological tissues using one sample is presented.