University College London (UCL)

6 ARTICLES PUBLISHED IN JoVE

Biology

Direct Protein Delivery to Mammalian Cells Using Cell-permeable Cys₂-His₂ Zinc-finger Domains

¹Departments of Chemistry and Cell and Molecular Biology, The Scripps Research Institute, ²Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University

Zinc-finger domains are intrinsically cell-permeable and capable of mediating protein delivery into a broad range of mammalian cell types. Here, a detailed step-by-step protocol for implementing zinc-finger technology for intracellular protein delivery is presented.

Neuroscience

Optogenetic Functional MRI

Peter Lin¹, Zhongnan Fang², Jia Liu¹, Jin Hyung Lee^1,2

¹Neurology and Neurological Sciences, Stanford University, ²Electrical Engineering, Neurology and Neurological Sciences, Stanford University

This protocol describes the steps and data analysis required to successfully perform optogenetic functional magnetic resonance imaging (ofMRI). ofMRI is a novel technique that combines high-field fMRI readout with optogenetic stimulation, allowing for cell type-specific mapping of functional neural circuits and their dynamics across the whole living brain.

Engineering

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

Colin R. Crick^*1, Sacha Noimark^*2,3, William J. Peveler^*3, Joseph C. Bear³, Aleksandar P. Ivanov¹, Joshua B. Edel¹, Ivan P. Parkin³

¹Department of Chemistry, Imperial College London, ²Department of Medical Physics and Biomedical Engineering, University College London, ³Department of Chemistry, University College London

Here we present a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of cadmium selenide quantum dots can be accurately visualized through cross-sectional fluorescence imaging.

Bioengineering

Biomechanical Characterization of Human Soft Tissues Using Indentation and Tensile Testing

Michelle Griffin¹, Yaami Premakumar², Alexander Seifalian¹, Peter Edward Butler^1,3, Matthew Szarko²

¹Division of Surgery & Interventional Science, University College London (UCL), ²Anatomy Department, St Georges University, ³Plastic & Reconstructive Surgery Department, Royal Free Hospital

Tissue biomechanics is important for maintaining cell shape and function and for determining phenotype. This report demonstrates non-destructive mechanical protocols for characterizing elastic and viscoelastic properties of human soft tissues, which can be directly applied to tissue-engineered substrates to allow a close matching of engineered materials to native tissue.

Chemistry

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

Weng-I Katherine Chio¹, Gemma Davison¹, Tabitha Jones¹, Jia Liu¹, Ivan P. Parkin¹, Tung-Chun Lee^1,2

¹Department of Chemistry, University College London (UCL), ²Institute for Materials Discovery, University College London (UCL)

A host-guest complex of cucurbit[7]uril and uric acid was formed in an aqueous solution before adding a small amount into Au NP solution for quantitative surface-enhanced Raman spectroscopy (SERS) sensing using a modular spectrometer.

Biochemistry

Purification of Endogenous Drosophila Transient Receptor Potential Channels

Jia Liu^*1, Yuyang Liu^*1, Weidi Chen¹, Yuzhen Ding¹, Xiaoru Lan¹, Wei Liu¹

¹Shenzhen Key Laboratory for Neuronal Structural Biology, Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center

Based on the assembling mechanism of the INAD protein complex, in this protocol, a modified affinity purification plus competition strategy was developed to purify the endogenous Drosophila TRP channel.