The gene repressor complex NuRD interacts with the histone variant H3.3 at promoters of active genes.

The histone variant H3.3 is deposited across active genes, regulatory regions, and telomeres. It remains unclear how H3.

Variation of DNA Methylome of Zebrafish Cells under Cold Pressure.

DNA methylation is an essential epigenetic mechanism involved in multiple biological processes. However, the relationship between DNA methylation and cold acclimation remains poorly understood. In this study, Methylated DNA Immunoprecipitation Sequencing (MeDIP-seq) was performed to reveal a genome-wide methylation profile of zebrafish (Danio rerio) embryonic fibroblast cells (ZF4) and its variation under cold pressure.

Evolutionary suppression of erythropoiesis via the modulation of TGF-β signalling in an Antarctic icefish.

The Antarctic icefish, a family (Channichthyidae) of teleosts within the perciform suborder Notothenioidei, are the only known vertebrates without oxygen-transporting haemoglobins and that are largely devoid of circulating erythrocytes. To elucidate the evo-devo mechanisms underpinning the suppressed erythropoiesis in the icefish, we conducted comparative studies on the transcriptomes and microRNAomes of the primary haematopoietic tissues between an icefish (Chionodraco hamatus) and two red-blooded notothenioids (Trematomus bernacchii and Gymnodraco acuticeps). We identified substantial remodelling of the haematopoietic programs in the icefish through which erythropoiesis is selectively suppressed.

Pash 3.0: A versatile software package for read mapping and integrative analysis of genomic and epigenomic variation using massively parallel DNA sequencing.

Background: Massively parallel sequencing readouts of epigenomic assays are enabling integrative genome-wide analyses of genomic and epigenomic variation. Pash 3.0 performs sequence comparison and read mapping and can be employed as a module within diverse configurable analysis pipelines, including ChIP-Seq and methylome mapping by whole-genome bisulfite sequencing.

A gene family-based method for interspecies comparisons of sequencing-based transcriptomes and its use in environmental adaptation analysis.

We describe a new method for sequencing-based cross-species transcriptome comparisons and define a new metric for evaluating gene expression across species using protein-coding families as units of comparison. Using this measure transcriptomes from different species were evaluated by mapping them to gene families and integrating the mapping results with expression data. Statistical tests were applied to the transcriptome evaluation results to identify differentially expressed families.

Characterization of microRNAs in cephalochordates reveals a correlation between microRNA repertoire homology and morphological similarity in chordate evolution.

Cephalochordates, urochordates, and vertebrates comprise the three extant groups of chordates. Although higher morphological and developmental similarity exists between cephalochordates and vertebrates, molecular phylogeny studies have instead suggested that the morphologically simplified urochordates are the closest relatives to vertebrates. MicroRNAs (miRNAs) are regarded as the major factors driving the increase of morphological complexity in early vertebrate evolution, and are extensively characterized in vertebrates and in a few species of urochordates.

Transcriptomic and genomic evolution under constant cold in Antarctic notothenioid fish.

The antifreeze glycoprotein-fortified Antarctic notothenioid fishes comprise the predominant fish suborder in the isolated frigid Southern Ocean. Their ecological success undoubtedly entailed evolutionary acquisition of a full suite of cold-stable functions besides antifreeze protection. Prior studies of adaptive changes in these teleost fishes generally examined a single genotype or phenotype.

Adaptive evolution of hepcidin genes in antarctic notothenioid fishes.

Hepcidin is a small bioactive peptide with dual roles as an antimicrobial peptide and as the principal hormonal regulator of iron homeostasis in human and mouse. Hepcidin homologs of very similar structures are found in lower vertebrates, all comprise approximately 20-25 amino acids with 8 highly conserved cysteines forming 4 intramolecular disulfide bonds, giving hepcidin a hairpin structure. Hepcidins are particularly diverse in teleost fishes, which may be related to the diversity of aquatic environments with varying degree of pathogen challenge, oxygenation, and iron concentration, factors known to alter hepcidin expression in mammals.

A hybrid Bayesian network learning method for constructing gene networks.

A Bayesian network (BN) is a knowledge representation formalism that has proven to be a promising tool for analyzing gene expression data. Several problems still restrict its successful applications. Typical gene expression databases contain measurements for thousands of genes and no more than several hundred samples, but most existing BNs learning algorithms do not scale more than a few hundred variables.

Trehalose as a good candidate for enriching full-length cDNAs in cDNA library construction.

It has been reported that the disaccharide trehalose is capable of increasing the thermostability and thermoactivity of reverse transcriptase, and therefore improving the length of cDNA synthesis. However, no test has been done on how the disaccharide trehalose performs in the context of the entire cDNA synthesis processes, or whether it can seamlessly integrate into the commercially available cDNA synthesis kit. In this report, we optimized a protocol to incorporate trehalose in the Stratagene's cDNA library construction kit in order to demonstrate great improvement in cDNA's length (average length of 1.

GO-Diff: mining functional differentiation between EST-based transcriptomes.

Background: Large-scale sequencing efforts produced millions of Expressed Sequence Tags (ESTs) collectively representing differentiated biochemical and functional states. Analysis of these EST libraries reveals differential gene expressions, and therefore EST data sets constitute valuable resources for comparative transcriptomics. To translate differentially expressed genes into a better understanding of the underlying biological phenomena, existing microarray analysis approaches usually involve the integration of gene expression with Gene Ontology (GO) databases to derive comparable functional profiles.