Adeno-associated viral vectors (AAV) are frequently used by neuroscientists to deliver tools, such as biosensors and optogenetic and chemogenetic actuators, . Despite its widespread use, AAV vector characterization and quality control can vary between labs and viral vector cores leading to variable results and irreproducibility. This protocol describes some of the characterization and quality control assays necessary to confirm an AAV vector's titer, genomic identity, serotype and purity.
View Article and Find Full Text PDFThe ability to precisely control transgene expression is essential for basic research and clinical applications. Adeno-associated viruses (AAVs) are non-pathogenic and can be used to drive stable expression in virtually any tissue, cell type, or species, but their limited genomic payload results in a trade-off between the transgenes that can be incorporated and the complexity of the regulatory elements controlling their expression. Resolving these competing imperatives in complex experiments inevitably results in compromises.
View Article and Find Full Text PDFRecombinant adeno-associated virus (rAAV) vectors are increasingly popular gene delivery tools in biological systems. They are safe and lead to high-level, long-term transgene expression. rAAV are available in multiple serotypes, natural or engineered, which enable targeting to a wide array of tissues and cell types.
View Article and Find Full Text PDFCell-type-specific expression of molecular tools and sensors is critical to construct circuit diagrams and to investigate the activity and function of neurons within the nervous system. Strategies for targeted manipulation include combinations of classical genetic tools such as Cre/loxP and Flp/FRT, use of cis-regulatory elements, targeted knock-in transgenic mice, and gene delivery by AAV and other viral vectors. The combination of these complex technologies with the goal of precise neuronal targeting is a challenge in the lab.
View Article and Find Full Text PDFCurr Protoc Mol Biol
July 2016
CRISPR/Cas9 technology is ideally suited for genome-wide screening applications due to the ease of generating guide RNAs (gRNAs) and the versatility of Cas9 or Cas9 derivatives to knockout, repress, or activate expression of target genes. Several pooled lentiviral CRISPR libraries have been developed and are now publicly available, but while using CRISPR/Cas9 for genetic experiments has become widely adopted, genome-wide screening experiments remain technically challenging. This review covers the basics of CRISPR/Cas9, describes several publicly available CRISPR libraries, and provides a general protocol for conducting genome-wide screening experiments using CRISPR/Cas9.
View Article and Find Full Text PDFThe recent Zika virus outbreak highlights the need for low-cost diagnostics that can be rapidly developed for distribution and use in pandemic regions. Here, we report a pipeline for the rapid design, assembly, and validation of cell-free, paper-based sensors for the detection of the Zika virus RNA genome. By linking isothermal RNA amplification to toehold switch RNA sensors, we detect clinically relevant concentrations of Zika virus sequences and demonstrate specificity against closely related Dengue virus sequences.
View Article and Find Full Text PDFPeroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) is a transcriptional coactivator involved in several aspects of energy metabolism. It is induced or activated under different stimuli in a highly tissue-specific manner and subsequently partners with certain transcription factors in those tissues to execute various biological programs. In the fasted liver, PGC-1alpha is induced and interacts with hepatocyte nuclear factor 4alpha (HNF4alpha) and other transcription factors to activate gluconeogenesis and increase hepatic glucose output.
View Article and Find Full Text PDFPGC-1alpha is a coactivator of nuclear receptors and other transcription factors that regulates several metabolic processes, including mitochondrial biogenesis and respiration, hepatic gluconeogenesis, and muscle fiber-type switching. We show here that, while hepatocytes lacking PGC-1alpha are defective in the program of hormone-stimulated gluconeogenesis, the mice have constitutively activated gluconeogenic gene expression that is completely insensitive to normal feeding controls. C/EBPbeta is elevated in the livers of these mice and activates the gluconeogenic genes in a PGC-1alpha-independent manner.
View Article and Find Full Text PDFThe transcriptional coactivator PPAR gamma coactivator 1 alpha (PGC-1alpha) is a key regulator of metabolic processes such as mitochondrial biogenesis and respiration in muscle and gluconeogenesis in liver. Reduced levels of PGC-1alpha in humans have been associated with type II diabetes. PGC-1alpha contains a negative regulatory domain that attenuates its transcriptional activity.
View Article and Find Full Text PDFThe liver plays several critical roles in the metabolic adaptation to fasting. We have shown previously that the transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) is induced in fasted or diabetic liver and activates the entire program of gluconeogenesis. PGC-1alpha interacts with several nuclear receptors known to bind gluconeogenic promoters including the glucocorticoid receptor, hepatocyte nuclear factor 4alpha (HNF4alpha), and the peroxisome proliferator-activated receptors.
View Article and Find Full Text PDF