Search results for "genomic"
showing 10 items of 1737 documents
The All-Rounder Sodalis: A New Bacteriome-Associated Endosymbiont of the Lygaeoid Bug Henestaris halophilus (Heteroptera: Henestarinae) and a Critica…
2017
International audience; Hemipteran insects are well-known in their ability to establish symbiotic relationships with bacteria. Among them, heteropteran insects present an array of symbiotic systems, ranging from the most common gut crypt symbiosis to the more restricted bacteriome-associated endosymbiosis, which have only been detected in members of the superfamily Lygaeoidea and the family Cimicidae so far. Genomic data of heteropteran endosymbionts are scarce and have merely been analyzed from the Wolbachia endosymbiont in bed bug and a few gut crypt-associated symbionts in pentatomoid bugs. In this study, we present the first detailed genomic analysis of a bacteriome-associated endosymbi…
The rise and the fall of a Pseudomonas aeruginosa endemic lineage in a hospital
2021
The biological features that allow a pathogen to survive in the hospital environment are mostly unknown. The extinction of bacterial epidemics in hospitals is mostly attributed to changes in medical practice, including infection control, but the role of bacterial adaptation has never been documented. We analysed a collection of Pseudomonas aeruginosa isolates belonging to the Besançon Epidemic Strain (BES), responsible for a 12year nosocomial outbreak, using a genotype-to-phenotype approach. Bayesian analysis estimated the emergence of the clone in the hospital 5 years before its opening, during the creation of its water distribution network made of copper. BES survived better than the refe…
Origin of the metazoan bodyplan: characterization and functional testing of the promoter of the homeobox gene EmH-3 from the freshwater sponge Ephyda…
1998
Porifera [sponges] represent the lowest metazoan phylum, probably already existing prior to the 'Cambrian explosion'. Based on amino acid sequences deduced from cDNAs that code for structural proteins, the monophyly of Metazoa was established. Now we analyzed for the first time a promoter of a sponge gene for its activity in a heterologous cell system from higher Metazoa. The promoter of the homeobox gene EmH-3 was cloned and sequenced from a genomic library of the freshwater sponge Ephydatia muelleri. For the determination of functional promoter activity, transient transfection experiments in mouse NIH 3T3 cells were performed; the promoter was fused with the luciferase reporter gene. The …
Transformation of follicular lymphoma to diffuse large cell lymphoma is associated with a heterogeneous set of DNA copy number and gene expression al…
2002
AbstractGenomic aberrations in a series of paired biopsy samples from patients who presented initially with follicle center lymphoma (FCL) and subsequently transformed to diffuse large B-cell lymphoma (DLBCL) were measured by array comparative genomic hybridization (CGH). The consequences of these aberrations on gene expression were determined by comparison with expression analysis on these specimens using cDNA microarrays. A heterogeneous pattern of acquired genomic abnormalities was observed upon transformation, some of which were recurrent in small subsets of patients. Some of the genomic aberration acquired upon transformation, such as gain/amplification of 1q21-q24, 2p16 (REL/BCL11A ge…
Different genomic organization and expression of immunoglobulin light-chain isotypes in the rainbow trout.
2000
cDNA studies have distinguished two isotypes of the rainbow trout (Oncorhynchus mykiss) immunoglobulin (Ig) light chain (designated L1 and L2). This study characterized genomic clones of these isotypes. L1 genes are arranged in clusters with single copies of variable (V), joining (J), and constant (C) segments. The transcriptional orientation of the V genes is opposite to that of the J and C segments, indicating that the V genes must be rearranged by inversion. L2 is also organized in clusters, consisting of two or three V, one J, and one C exon, all in the same transcriptional orientation. L1 and L2 of rainbow trout are similar to the previously identified cod and catfish clusters. Repeat …
Expression profiling of uniparental mouse embryos is inefficient in identifying novel imprinted genes
2006
AbstractImprinted genes are expressed from only one allele in a parent-of-origin-specific manner. We here describe a systematic approach to identify novel imprinted genes using quantification of allele-specific expression by Pyrosequencing, a highly accurate method to detect allele-specific expression differences. Sixty-eight candidate imprinted transcripts mapping to known imprinted chromosomal regions were selected from a recent expression profiling study of uniparental mouse embryos and analyzed. Three novel imprinted transcripts encoding putative non-protein-coding RNAs were identified on the basis of parent-of-origin-specific monoallelic expression in E11.5 (C57BL/6 × Cast/Ei)F1 and in…
Metatranscriptomic Approach to Analyze the Functional Human Gut Microbiota
2011
The human gut is the natural habitat for a large and dynamic bacterial community that has a great relevance for health. Metagenomics is increasing our knowledge of gene content as well as of functional and genetic variability in this microbiome. However, little is known about the active bacteria and their function(s) in the gastrointestinal tract. We performed a metatranscriptomic study on ten healthy volunteers to elucidate the active members of the gut microbiome and their functionality under conditions of health. First, the microbial cDNAs obtained from each sample were sequenced using 454 technology. The analysis of 16S transcripts showed the phylogenetic structure of the active microbi…
Computational annotation of genes differentially expressed along olive fruit development
2009
Abstract Background Olea europaea L. is a traditional tree crop of the Mediterranean basin with a worldwide economical high impact. Differently from other fruit tree species, little is known about the physiological and molecular basis of the olive fruit development and a few sequences of genes and gene products are available for olive in public databases. This study deals with the identification of large sets of differentially expressed genes in developing olive fruits and the subsequent computational annotation by means of different software. Results mRNA from fruits of the cv. Leccino sampled at three different stages [i.e., initial fruit set (stage 1), completed pit hardening (stage 2) a…
Sequence and analysis of chromosome 3 of the plant Arabidopsis thaliana.
2000
Arabidopsis thaliana is an important model system for plant biologists. In 1996 an international collaboration (the Arabidopsis Genome Initiative) was formed to sequence the whole genome of Arabidopsis and in 1999 the sequence of the first two chromosomes was reported. The sequence of the last three chromosomes and an analysis of the whole genome are reported in this issue. Here we present the sequence of chromosome 3, organized into four sequence segments (contigs). The two largest (13.5 and 9.2 Mb) correspond to the top (long) and the bottom (short) arms of chromosome 3, and the two small contigs are located in the genetically defined centromere. This chromosome encodes 5,220 of the rough…
Not just BLAST nt: WGS database joins the party
2019
AbstractSince its introduction in 1990 and with over 50k citations, the NCBI BLAST family has been an essential tool of in silico molecular biology. The BLAST nt database, based on the traditional divisions of GenBank, has been the default and most comprehensive database for nucleotide BLAST searches and for taxonomic classification software in metagenomics. Here we argue that this is no longer the case. Currently, the NCBI WGS database contains one billion reads (almost five times more than GenBank), and with 4.4 trillion nucleotides, WGS has about 14 times more nucleotides than GenBank. This ratio is growing with time. We advocate a change in the database paradigm in taxonomic classificat…