Salk Institute for Biological Studies 2 articles published in JoVE Biochemistry Single-Particle Cryo-EM Data Collection with Stage Tilt using Leginon Sriram Aiyer1, Timothy S. Strutzenberg1, Marianne E. Bowman2, Joseph P. Noel2,3, Dmitry Lyumkis1,4,5 1Laboratory of Genetics, The Salk Institute for Biological Studies, 2Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, 3Department of Chemistry and Biochemistry, University of California San Diego, 4Graduate School of Biological Sciences, Section of Molecular Biology, University of California San Diego, 5Department of Integrative Structural and Computational Biology, The Scripps Research Institute The present protocol describes a generalized and easy-to-implement scheme for tilted single-particle data collection in cryo-EM experiments. Such a procedure is especially useful for obtaining a high-quality EM map for samples suffering from preferential orientation bias due to adherence to the air-water interface. Neuroscience Optical Control of a Neuronal Protein Using a Genetically Encoded Unnatural Amino Acid in Neurons Ji-Yong Kang1, Daichi Kawaguchi2, Lei Wang3 1Department of Neuroscience, School of Medicine, Tufts University, 2Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 3Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California, San Francisco Here, a procedure to selectively activate a neuronal protein with a short pulse of light by genetically encoding a photo-reactive unnatural amino acid into a target neuronal protein expressed in neurons in culture or in vivo is presented.