Articles by Justin Farlow in JoVE
Production and Targeting of Monovalent Quantum Dots Daeha Seo*1,2,3, Justin Farlow*4,5,6, Kade Southard1,4,7, Young-wook Jun1,7, Zev J. Gartner4,5,6,7 1Department of Otolaryngology, University of California, San Francisco, 2Department of Chemistry, University of California, Berkeley, 3Materials Science Division, Lawrence Berkeley National Laboratory, 4Department of Pharmaceutical Chemistry, University of California, San Francisco, 5Tetrad Graduate Program, University of California, San Francisco, 6Center for Systems and Synthetic Biology, University of California, San Francisco, 7Chemistry and Chemical Biology Graduate Program, University of California, San Francisco We provide detailed instructions for the preparation of monovalent targeted quantum dots (mQDs) from phosphorothioate DNA of defined length. DNA wrapping occurs in high yield, and therefore, products do not require purification. We demonstrate the use of the SNAP tag to target mQDs to cell-surface receptors for live-cell imaging applications.
Other articles by Justin Farlow on PubMed
Not All Quiet on the Noise Front Nature Chemical Biology. Oct, 2009 | Pubmed ID: 19763097 Phenotypic diversity exists even within isogenic populations of cells. Such nongenetic individuality may have wide implications for our understanding of many biological processes. The field of study concerned with the investigation of nongenetic individuality, also known as the 'biology of noise', is ripe with exciting scientific opportunities and challenges.
Programmed Cell-to-Cell Variability in Ras Activity Triggers Emergent Behaviors During Mammary Epithelial Morphogenesis Cell Reports. Oct, 2012 | Pubmed ID: 23041312 Variability in signaling pathway activation between neighboring epithelial cells can arise from local differences in the microenvironment, noisy gene expression, or acquired genetic changes. To investigate the consequences of this cell-to-cell variability in signaling pathway activation on coordinated multicellular processes such as morphogenesis, we use DNA-programmed assembly to construct three-dimensional MCF10A microtissues that are mosaic for low-level expression of activated H-Ras. We find two emergent behaviors in mosaic microtissues: cells with activated H-Ras are basally extruded or lead motile multicellular protrusions that direct the collective motility of their wild-type neighbors. Remarkably, these behaviors are not observed inÂ homogeneous microtissues in which all cells expressÂ the activated Ras protein, indicating that heterogeneity in Ras activity, rather than the total amount of Ras activity, is critical for these processes. Our results directly demonstrate that cell-to-cell variability in pathway activation within local populations of epithelial cells can drive emergent behaviors during epithelial morphogenesis.
Formation of Targeted Monovalent Quantum Dots by Steric Exclusion Nature Methods. Dec, 2013 | Pubmed ID: 24122039 Precise control over interfacial chemistry between nanoparticles and other materials remains a major challenge that limits broad application of nanotechnology in biology. To address this challenge, we used 'steric exclusion' to completely convert commercial quantum dots (QDs) into monovalent imaging probes by wrapping each QD with a functionalized oligonucleotide. We demonstrated the utility of these QDs as modular and nonperturbing imaging probes by tracking individual Notch receptors on live cells.