Search results for "RNA extraction"

Transcriptional Differences between Diapausing and Non-Diapausing D. montana Females Reared under the Same Photoperiod and Temperature

2016

Background A wide range of insects living at higher latitudes enter diapause at the end of the warm season, which increases their chances of survival through harsh winter conditions. In this study we used RNA sequencing to identify genes involved in adult reproductive diapause in a northern fly species, Drosophila montana. Both diapausing and non-diapausing flies were reared under a critical day length and temperature, where about half of the emerging females enter diapause enabling us to eliminate the effects of varying environmental conditions on gene expression patterns of the two types of female flies. Results RNA sequencing revealed large differences between gene expression patterns of…

Removing Batch Effects from Longitudinal Gene Expression - Quantile Normalization Plus ComBat as Best Approach for Microarray Transcriptome Data

2016

International audience; Technical variation plays an important role in microarray-based gene expression studies, and batch effects explain a large proportion of this noise. It is therefore mandatory to eliminate technical variation while maintaining biological variability. Several strategies have been proposed for the removal of batch effects, although they have not been evaluated in large-scale longitudinal gene expression data. In this study, we aimed at identifying a suitable method for batch effect removal in a large study of microarray-based longitudinal gene expression. Monocytic gene expression was measured in 1092 participants of the Gutenberg Health Study at baseline and 5-year fol…

2016

RNA 2'-O-methylation is one of the ubiquitous nucleotide modifications found in many RNA types from Bacteria, Archaea and Eukarya. RNAs bearing 2'-O-methylations show increased resistance to degradation and enhanced stability in helices. While the exact role of each 2'-O-Me residue remained elusive, the catalytic protein Fibrillarin (Nop1 in yeast) responsible for 2'-O-methylation in eukaryotes, is associated with human pathologies. Therefore, there is an urgent need to precisely map and quantify hundreds of 2'-O-Me residues in RNA using high-throughput technologies. Here, we develop a reliable protocol using alkaline fragmentation of total RNA coupled to a commonly used ligation approach, …

Co-infection with iflaviruses influences the insecticidal properties of Spodoptera exigua multiple nucleopolyhedrovirus occlusion bodies: Implication…

2017

Biological insecticides based on Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) can efficiently control S. exigua larvae on field and greenhouse crops in many parts of the world. Spanish wild populations and laboratory colonies of S. exigua are infected by two iflaviruses (SeIV-1 and SeIV-2). Here we evaluated the effect of iflavirus co-infection on the insecticidal characteristics of SeMNPV occlusion bodies (OBs). Overall, iflavirus co-inoculation consistently reduced median lethal concentrations (LC50) for SeMNPV OBs compared to larvae infected with SeMNPV alone. However, the speed of kill of SeMNPV was similar in the presence or absence of the iflaviruses. A reduction of the we…

Optimised lyophilisation-based method for different biomolecule single-extractions from the same rat brain sample: Suitability for RNA and protein ex…

2019

Abstract Background Optimisation of tissue processing procedures in preclinical studies reduces the number of animals used and allows integrated multilevel study in the same sample. Multiple extraction of different biomolecules from the same sample has several limitations. New method Using brain samples from rats subjected to ischemic stroke, we combined lyophilisation of flash-frozen tissue, mechanical pulverisation and cryopreservation in a method to optimise tissue handling and preservation for independent RNA or protein single-extract methods, and subsequent RT-qPCR or Western blot analyses. Results Lyophilisation resulted in 70% tissue weight loss. RNA (OD260/280∼1.8) and protein yield…

Mechanical strain causes adaptive change in bronchial fibroblasts enhancing profibrotic and inflammatory responses

2016

Asthma is characterized by periodic episodes of bronchoconstriction and reversible airway obstruction; these symptoms are attributable to a number of factors including increased mass and reactivity of bronchial smooth muscle and extracellular matrix (ECM) in asthmatic airways. Literature has suggested changes in cell responses and signaling can be elicited via modulation of mechanical stress acting upon them, potentially affecting the microenvironment of the cell. In this study, we hypothesized that mechanical strain directly affects the (myo)fibroblast phenotype in asthma. Therefore, we characterized responses of bronchial fibroblasts, from 6 normal and 11 asthmatic non-smoking volunteers,…

A method to isolate cDNA-quality RNA from adult conifer needles and a psbA cDNA from Norway spruce

1996

Summary In order to investigate the expression of the psbA gene in damaged and undamaged Norway spruce trees ( Picea abies ) a cDNA clone encoding the D1 protein was isolated via RT-PCR. Applying a method developed by Schneiderbauer et al. (1991) with some modifications, we were able to obtain the required RNA from mature needles and successfully reverse transcribe it into cDNA. Sequence analysis of the cDNA clone revealed an open reading frame (ORF) encoding a 353 amino acid polypeptide that is highly homologous to the D1 protein sequences deduced from higher plant psbA genes. A 4 bp insertion, directly following the stop codon ochre (TAA), was found by comparison with two Pinus species, t…

Selective MicroRNA-Offset RNA Expression in Human Embryonic Stem Cells

2015

Small RNA molecules, including microRNAs (miRNAs), play critical roles in regulating pluri-potency, proliferation and differentiation of embryonic stem cells. miRNA-offset RNAs (moRNAs) are similar in length to miRNAs, align to miRNA precursor (pre-miRNA) loci and are therefore believed to derive from processing of the pre-miRNA hairpin sequence. Recent next generation sequencing (NGS) studies have reported the presence of moRNAs in human neurons and cancer cells and in several tissues in mouse, including pluripotent stem cells. In order to gain additional knowledge about human moRNAs and their putative development-related expression, we applied NGS of small RNAs in human embryonic stem cel…

Tumor- and cytokine-primed human natural killer cells exhibit distinct phenotypic and transcriptional signatures.

2019

An emerging cellular immunotherapy for cancer is based on the cytolytic activity of natural killer (NK) cells against a wide range of tumors. Although in vitro activation, or "priming," of NK cells by exposure to pro-inflammatory cytokines, such as interleukin (IL)-2, has been extensively studied, the biological consequences of NK cell activation in response to target cell interactions have not been thoroughly characterized. We investigated the consequences of co-incubation with K562, CTV-1, Daudi RPMI-8226, and MCF-7 tumor cell lines on the phenotype, cytokine expression profile, and transcriptome of human NK cells. We observe the downregulation of several activation receptors including CD…

Isolation of Zebrafish Gonads for RNA Isolation

2013

Piwi proteins and piRNAs are abundant in the gonads of various animal species. Gonads from different developmental stages provide us information regarding the function of piRNAs and the PIWI pathway during germline development. Here we describe methods for gonad and germ cell preparation from different developmental stages of zebrafish. We also describe how to use these gonads to purify and characterize piRNAs.