University of Toronto, Mississauga 4 articles published in JoVE Neuroscience Quantification of Visual Feature Selectivity of the Optokinetic Reflex in Mice Jiashu Liu1,2, Bao-hua Liu1,2 1Department of Biology, University of Toronto Mississauga, 2Department of Cell and Systems Biology, University of Toronto Here, we describe a standard protocol for quantifying the optokinetic reflex. It combines virtual drum stimulation and video-oculography, and thus allows precise evaluation of the feature selectivity of the behavior and its adaptive plasticity. Bioengineering Methods for Electroporation and Transformation Confirmation in Limosilactobacillus reuteri DSM20016 Alexander Duggan1, David McMillen1 1University of Toronto Mississauga Here, we present protocols for working with Limosilactobacillus reuteri DSM20016, detailing growth, plasmid transformation, colony PCR, fluorescent reporter protein measurement, and limited plasmid mini-prep, as well as common issues and troubleshooting. These protocols allow the measurement of reporter proteins in DSM20016, or confirmation via colony PCR if no reporter is involved. Genetics High-Resolution Mapping of Protein-DNA Interactions in Mouse Stem Cell-Derived Neurons using Chromatin Immunoprecipitation-Exonuclease (ChIP-Exo) Kaitlin N. Montanera1,2, Ho Sung Rhee1,2 1Department of Cell and Systems Biology, University of Toronto, 2Department of Biology, University of Toronto Precise determination of protein-binding locations across the genome is important for understanding gene regulation. Here we describe a genomic mapping method that treats chromatin-immunoprecipitated DNA with exonuclease digestion (ChIP-exo) followed by high-throughput sequencing. This method detects protein-DNA interactions with near base-pair mapping resolution and high signal-to-noise ratio in mammalian neurons. Cancer Research Differentiation of Mouse Breast Epithelial HC11 and EpH4 Cells Mulu Geletu*1,2, Victoria Hoskin*1, Blerta Starova*1,3, Maximilian Niit1,4, Hanad Adan1, Bruce Elliott1, Patrick Gunning2, Leda Raptis1 1 We describe techniques for differentiation induction of two breast epithelial lines, HC11 and EpH4. While both require fetal calf serum, insulin, and prolactin to produce milk proteins, EpH4 cells can fully differentiate into mammospheres in three-dimensional culture. These complementary models are useful for signal transduction studies of differentiation and neoplasia.