Alternative splicing produces various mRNAs, and thereby various protein products, from one gene, impacting a wide range of cellular activities. However, accurate reconstruction and quantification of full-length transcripts using short-reads is limited, due to their length. Long-reads sequencing technologies may provide a solution by sequencing full-length transcripts.
View Article and Find Full Text PDFAdvances in whole genome amplification (WGA) techniques enable understanding of the genomic sequence at a single cell level. Demand for single cell dedicated WGA kits (scWGA) has led to the development of several commercial kit. To this point, no robust comparison of all available kits was performed.
View Article and Find Full Text PDFLong noncoding RNAs (lncRNAs) have been shown to play important roles in gene regulatory networks acting in early development. There has been rapid turnover of lncRNA loci during vertebrate evolution, with few human lncRNAs conserved beyond mammals. The sequences of these rare deeply conserved lncRNAs are typically not similar to each other.
View Article and Find Full Text PDFRecent years have seen a dramatic improvement in protein-design methodology. Nevertheless, most methods demand expert intervention, limiting their widespread adoption. By contrast, the PROSS algorithm for improving protein stability and heterologous expression levels has been successfully applied to a range of challenging enzymes and binding proteins.
View Article and Find Full Text PDFMotor neuron-specific microRNA-218 (miR-218) has recently received attention because of its roles in mouse development. However, miR-218 relevance to human motor neuron disease was not yet explored. Here, we demonstrate by neuropathology that miR-218 is abundant in healthy human motor neurons.
View Article and Find Full Text PDFDeregulated activity of LArge Tumor Suppressor (LATS) tumor suppressors has broad implications on cellular and tissue homeostasis. We examined the consequences of down-regulation of either LATS1 or LATS2 in breast cancer. Consistent with their proposed tumor suppressive roles, expression of both paralogs was significantly down-regulated in human breast cancer, and loss of either paralog accelerated mammary tumorigenesis in mice.
View Article and Find Full Text PDFOver the last decade, we have developed a molecular-controlled semiconductor resistor (MOCSER) device that is highly sensitive to variations in its surface potentials. This device was applied as a molecular sensor both in the gas phase and in solutions. The device is based on an AlGaAs/GaAs structure.
View Article and Find Full Text PDFDNA methylation is a key regulator of embryonic stem cell (ESC) biology, dynamically changing between naïve, primed, and differentiated states. The p53 tumor suppressor is a pivotal guardian of genomic stability, but its contributions to epigenetic regulation and stem cell biology are less explored. We report that, in naïve mouse ESCs (mESCs), p53 restricts the expression of the de novo DNA methyltransferases Dnmt3a and Dnmt3b while up-regulating Tet1 and Tet2, which promote DNA demethylation.
View Article and Find Full Text PDFMultiple transcriptional and epigenetic changes drive differentiation of embryonic stem cells (ESCs). This study unveils an additional level of gene expression regulation involving noncanonical, cap-independent translation of a select group of mRNAs. This is driven by death-associated protein 5 (DAP5/eIF4G2/NAT1), a translation initiation factor mediating IRES-dependent translation.
View Article and Find Full Text PDFOne of the key applications of next-generation sequencing (NGS) technologies is RNA-Seq for transcriptome genome-wide analysis. Although multiple studies have evaluated and benchmarked RNA-Seq tools dedicated to gene level analysis, few studies have assessed their effectiveness on the transcript-isoform level. Alternative splicing is a naturally occurring phenomenon in eukaryotes, significantly increasing the biodiversity of proteins that can be encoded by the genome.
View Article and Find Full Text PDFDNA-damage tolerance (DDT) via translesion DNA synthesis (TLS) or homology-dependent repair (HDR) functions to bypass DNA lesions encountered during replication, and is critical for maintaining genome stability. Here, we present piggyBlock, a new chromosomal assay that, using piggyBac transposition of DNA containing a known lesion, measures the division of labor between the two DDT pathways. We show that in the absence of DNA damage response, tolerance of the most common sunlight-induced DNA lesion, TT-CPD, is achieved by TLS in mouse embryo fibroblasts.
View Article and Find Full Text PDFStable maintenance of gene regulatory programs is essential for normal function in multicellular organisms. Epigenetic mechanisms, and DNA methylation in particular, are hypothesized to facilitate such maintenance by creating cellular memory that can be written during embryonic development and then guide cell-type-specific gene expression. Here we develop new methods for quantitative inference of DNA methylation turnover rates, and show that human embryonic stem cells preserve their epigenetic state by balancing antagonistic processes that add and remove methylation marks rather than by copying epigenetic information from mother to daughter cells.
View Article and Find Full Text PDFCell Death Differ
April 2014
Differentiation is a highly controlled process essential for embryonic and adult development. Moreover, disruption of proper differentiation is often associated with human diseases, including cancer. We analyzed the involvement of the tumor-suppressor Lats2 in mouse embryonic stem cell (mESC) pluripotency and differentiation, and report that mESCs lacking Lats2 are unable to sustain stemness and are not able to initiate and coordinate developmental transcriptional programs.
View Article and Find Full Text PDFBackground: Surface-expressed Na+/K+-ATPase (NaK) has been suggested to function as a non-canonical cardiotonic steroid-binding receptor that activates multiple signaling cascades, especially in cancer cells. By contrast, the current study establishes a clear correlation between the IC50in vitro growth inhibitory concentration in human cancer cells and the Ki for the inhibition of activity of purified human α1β1 NaK.
Methods: The in vitro growth inhibitory effects of seven cardiac glycosides including five cardenolides (ouabain, digoxin, digitoxin, gitoxin, uzarigenin-rhamnoside, and their respective aglycone forms) and two bufadienolides (gamabufotalin-rhamnoside and hellebrin, and their respective aglycone forms) were determined by means of the MTT colorimetric assay and hellebrigenin-induced cytotoxic effects were visualized by means of quantitative videomicroscopy.
TAF4b is a cell type-specific subunit of the general transcription factor TFIID. Here, we show that TAF4b is highly expressed in embryonic stem cells (ESC) and is down-regulated upon differentiation. To examine the role of TAF4b in ESC, we applied a knockdown (KD) approach.
View Article and Find Full Text PDFNeurosphere cells (NSc) derived from embryonic stem cells have characteristics of neural stem cells and can differentiate into oligodendrocyte precursors. Culture of NSc with IL6RIL6 chimera (soluble interleukin-6 receptor fused to interleukin-6) enhances their differentiation into oligodendrocytes with longer and more numerous branches and with peripheral accumulation of myelin basic protein (MBP) in myelin membranes indicating maturation. Gene expression profiling reveals that one of the proteins strongly induced by IL6RIL6 is a regulator of microtubule dynamics, stathmin-like 2 (SCG10/Stmn2), and gene silencing shows that Stmn2 plays an important role in the development of the mature oligodendrocyte morphology.
View Article and Find Full Text PDFNF-kappaB induces the expression of genes involved in immune response, apoptosis, inflammation, and the cell cycle. Certain NF-kappaB-responsive genes are activated rapidly after the cell is stimulated by cytokines and other extracellular signals. However, the mechanism by which these genes are activated is not entirely understood.
View Article and Find Full Text PDFInduction of murine glutathione-S-transferase (GST) Ya gene expression by a variety of chemical agents is mediated by a regulatory element, EpRE, composed of an Ets and two adjacent activator protein-1 (AP-1)-like sites and activated by the Fos/Jun heterodimeric complex (AP-1). The mechanism of this induction was examined in the present study. We find that the regulation of EpRE-mediated GST Ya gene expression by 3-methylcholanthrene, tert-butylhydroquinone and beta-naphthoflavone is associated with an induction of AP-1 DNA-binding activity and that the AP-1 complex induced in hepatoma cells by these chemicals contains members of the Fos and Jun protein families.
View Article and Find Full Text PDFRecept Signal Transduct
August 1998
3-methylcholanthrene (MC), a potent promutagen and procarcinogen, is also an inducer of mammalian CYPIAI (cytochrome P1-450) gene. The CYPIAI enzyme is responsible for the detoxification of MC and its oxidation into reactive epoxide intermediates. Through its epoxide metabolites, MC functions also as an inducer of drug-metabolizing enzyme glutathione S-transferase (GST) gene expression.
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