Phosphate (Pi) deficiency triggers the differential expression of a large set of genes, which communally adapt the plant to low Pi bioavailability. To infer functional modules in early transcriptional responses to Pi deficiency, we conducted time-course microarray experiments and subsequent coexpression-based clustering of Pi-responsive genes by pairwise comparison of genes against a customized database. Three major clusters, enriched in genes putatively functioning in transcriptional regulation, root hair formation, and developmental adaptations, were predicted from this analysis. Validation of gene expression by quantitative reverse transcription-PCR revealed that transcripts from randomly selected genes were robustly induced within the first hour after transfer to Pi-deplete medium. Pectin-related processes were among the earliest and most robust responses to Pi deficiency, indicating that cell wall alterations are critical in the early transcriptional response to Pi deficiency. Phenotypical analysis of homozygous mutants defective in the expression of genes from the root hair cluster revealed eight novel genes involved in Pi deficiency-induced root hair elongation. The plants responded rapidly to Pi deficiency by the induction of a subset of transcription factors, followed by a repression of genes involved in cell wall alterations. The combined results provide a novel, integrated view at a systems level of the root responses that acclimate Arabidopsis (Arabidopsis thaliana) to suboptimal Pi levels.

Bismuth quadruple therapy for H. pylori eradication can lead to short-term dysbiosis of gut microbiota. The increase in Proteobacteria in gut microbiota may attribute to the development of adverse effects during bismuth quadruple therapy.

Background and Aims:Anti-Helicobacter pylori therapy may lead to the growth of pathogenic or antibiotic-resistant bacteria in the gut. The study aimed to investigate the shortterm and long-term impacts of H. pylori eradication with reverse hybrid therapy on the components and macrolide resistance of the gut microbiota. Methods: Helicobacter pylori-related gastritis patients were administered a 14-day reverse hybrid therapy. Fecal samples were collected before treatment and at the end of week 2, week 8, and week 48. The V3-V4 region of the bacterial 16S rRNA gene in fecal specimens was amplified by polymerase chain reaction and sequenced on Illumina MiSeq platform. Additionally, amplification of erm(B) gene (encoding erythromycin resistance methylase) was performed. Results: Reverse hybrid therapy resulted in decreased relative abundances of Firmicutes (from 62.0% to 30.7%; P < 0.001) and Actinobacteria (from 3.4% to 0.6%; 0.032) at the end of therapy. In contrast, the relative abundance of Proteobacteria increased from 10.2% to 49.1% (0.002). These microbiota alterations did not persist but returned to the initial levels at week 8 and week 48. The amount of erm(B) gene in fecal specimens was comparable with the pretreatment level at week 2 but increased at week 8 (0.025) and then returned to the pretreatment level by week 48. Conclusions: Helicobacter pylori eradication with reverse hybrid therapy can lead to short-term gut dysbiosis. The amount of erm(B) gene in the stool increased transiently after treatment and returned to the pretreatment level at 1-year post-treatment.

Background: MicroRNAs (miRNAs) function in many physiological processes, and their discovery is beneficial for further studying their physiological functions. However, many of the miRNAs predicted from genomic sequences have not been experimentally validated to be authentic expressed RNA transcripts, thereby decreasing the reliability of miRNA discovery. To overcome this problem, we examined expressed transcripts -ESTs and intronic sequences -to identify novel miRNAs as well as their target genes.

Many reports have implicated that microRNAs involve in cancer development and progression, such as miR-155 in breast cancers and miR-196 in gastric cancers. Furthermore, microRNAs are more stable than typical protein-coding gene mRNAs in varieties of clinical samples including body fluids. This suggests that they are potentially valuable biomarkers for cancer monitoring. In this study, we have used urine samples of gastric cancer patients to demonstrate the feasibility of urine microRNAs for gastric cancer detection. Urine samples of gastric cancer patients were extracted for total RNA, which were examined for the expression of miR-21-5p using quantitative stem-loop PCR. Our results demonstrated that miR-21-5p could be detected in small amounts of urine samples with good stability, and the expression levels of miR-21-5p were reduced following surgical removal of gastric cancer tissues. These results implicate that urine miR-21-5p could be utilized as a novel non-invasive biomarker of gastric cancer detection and monitoring.

The dynamics of histone methylation have emerged as an important issue since the identification of histone demethylases. We studied the regulatory function of Rph1/KDM4 (lysine demethylase), a histone H3K36 demethylase, on transcription in Saccharomyces cerevisiae. Overexpression of Rph1 reduced the expression of PHR1 and increased UV sensitivity. The catalytically deficient mutant (H235A) of Rph1 diminished the repressive transcriptional effect on PHR1 expression, which indicates that histone demethylase activity contributes to transcriptional repression. Chromatin immunoprecipitation analysis demonstrated that Rph1 was associated at the upstream repression sequence of PHR1 through zinc-finger domains and was dissociated after UV irradiation. Notably, overexpression of Rph1 and H3K36A mutant reduced histone acetylation at the URS, which implies a crosstalk between histone demethylation and acetylation at the PHR1 promoter. In addition, the crucial checkpoint protein Rad53 acted as an upstream regulator of Rph1 and dominated the phosphorylation of Rph1 that was required for efficient PHR1 expression and the dissociation of Rph1. The release of Rph1 from chromatin also required the phosphorylation at S652. Our study demonstrates that the histone demethylase Rph1 is associated with a specific chromatin locus and modulates histone modifications to repress a DNA damage responsive gene under control of damage checkpoint signaling.

The completion of human genome sequences and the advancement of next-generation sequencing technologies have engendered a clear understanding of all human genes. Overlapping genes are usually observed in compact genomes, such as those of bacteria and viruses. Notably, overlapping protein-coding genes do exist in human genome sequences. Accordingly, we used the current Ensembl gene annotations to identify overlapping human protein-coding genes. We analysed 19,200 well-annotated protein-coding genes and determined that 4,951 protein-coding genes overlapped with their adjacent genes. Approximately a quarter of all human protein-coding genes were overlapping genes. We observed different clusters of overlapping protein-coding genes, ranging from two genes (paired overlapping genes) to 22 genes. We also divided the paired overlapping protein-coding gene groups into four subtypes. We found that the divergent overlapping gene subtype had a stronger expression association than did the subtypes of 5ʹ-tandem overlapping and 3ʹ-tandem overlapping genes. The majority of paired overlapping genes exhibited comparable coincidental tissue expression profiles; however, a few overlapping gene pairs displayed distinctive tissue expression association patterns. In summary, we have carefully examined the genomic features and distributions about human overlapping protein-coding genes and found coincidental expression in tissues for most overlapping protein-coding genes.

With considerable accumulation of RNA-Seq transcriptome data, we have extended our understanding about protein-coding gene transcript compositions. However, alternatively compounded patterns of human protein-coding gene transcripts would complicate gene expression data processing and interpretation. It is essential to exhaustively interrogate complex mRNA isoforms of protein-coding genes with an unified data resource. In order to investigate representative mRNA transcript isoforms to be utilized as transcriptome analysis references, we utilized GTEx data to establish a top-ranked transcript isoform expression data resource for human protein-coding genes. Distinctive tissue specific expression profiles and modulations could be observed for individual top-ranked transcripts of protein-coding genes. Protein-coding transcripts or genes do occupy much higher expression fraction in transcriptome data. In addition, top-ranked transcripts are the dominantly expressed ones in various normal tissues. Intriguingly, some of the top-ranked transcripts are noncoding splicing isoforms, which imply diverse gene regulation mechanisms. Comprehensive investigation on the tissue expression patterns of top-ranked transcript isoforms is crucial. Thus, we established a web tool to examine top-ranked transcript isoforms in various human normal tissue types, which provides concise transcript information and easy-to-use graphical user interfaces. Investigation of top-ranked transcript isoforms would contribute understanding on the functional significance of distinctive alternatively spliced transcript isoforms.