Next-generation sequencing technologies have revolutionarily advanced sequence-based research with the advantages of high-throughput, high-sensitivity, and high-speed. RNA-seq is now being used widely for uncovering multiple facets of transcriptome to facilitate the biological applications. However, the large-scale data analyses associated with RNA-seq harbors challenges. In this study, we present a detailed overview of the applications of this technology and the challenges that need to be addressed, including data preprocessing, differential gene expression analysis, alternative splicing analysis, variants detection and allele-specific expression, pathway analysis, co-expression network analysis, and applications combining various experimental procedures beyond the achievements that have been made. Specifically, we discuss essential principles of computational methods that are required to meet the key challenges of the RNA-seq data analyses, development of various bioinformatics tools, challenges associated with the RNA-seq applications, and examples that represent the advances made so far in the characterization of the transcriptome.

Cytosine methylation is critical in mammalian development and plays a role in diverse biologic processes such as genomic imprinting, X chromosome inactivation, and silencing of repeat elements. Several factors regulate DNA methylation in early embryogenesis, but their precise role in the establishment of DNA methylation at a given site remains unclear. We have generated a comprehensive methylation map in fibroblasts derived from the murine DNA methylation mutant Hells -/-(helicase, lymphoid specific, also known as LSH). It has been previously shown that HELLS can influence de novo methylation of retroviral sequences and endogenous genes. Here, we describe that HELLS controls cytosine methylation in a nuclear compartment that is in part defined by lamin B1 attachment regions. Despite widespread loss of cytosine methylation at regulatory sequences, including promoter regions of protein-coding genes and noncoding RNA genes, overall relative transcript abundance levels in the absence of HELLS are similar to those in wild-type cells. A subset of promoter regions shows increases of the histone modification H3K27me3, suggesting redundancy of epigenetic silencing mechanisms. Furthermore, HELLS modulates CG methylation at all classes of repeat elements and is critical for repression of a subset of repeat elements. Overall, we provide a detailed analysis of gene expression changes in relation to DNA methylation alterations, which contributes to our understanding of the biological role of cytosine methylation.

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Supervisor–subordinate relations, guanxi , impression management, China,

Several studies have described phenotypic changes in the offspring of mice exposed to a variety of environmental factors, including diet, toxins, and stress; however, the molecular pathways involved in these changes remain unclear. Using a high fat diet (HFD)-induced obesity mouse model, we examined liver gene expression in male offspring and analyzed chromatin of paternal spermatozoa. We found that the hepatic mRNA level of 7 genes (out of 20 evaluated) was significantly altered in HFD male offspring compared to control mice, suggesting that phenotypic changes in the offspring depend on parental diet. We examined 7 imprinted loci in spermatozoa DNA from HFD-treated and control fathers by bisulfite sequencing, but did not detect changes in DNA methylation associated with HFD. Using chromatin immunoprecipitation followed by high-throughput sequencing, we found differential histone H3-occupancy at genes involved in the regulation of embryogenesis and differential H3K4me1-enrichment at transcription regulatory genes in HFD fathers vs. control mice. These results suggest that dietary exposure can modulate histone composition at regulatory genes implicated in developmental processes.

Lsh, a chromatin remodeling protein of the SNF2 family, is critical for normal heterochromatin structure. In particular, DNA methylation at repeat elements, a hallmark of heterochromatin, is greatly reduced in Lsh−/− (KO) cells. Here, we examined the presumed nucleosome remodeling activity of Lsh on chromatin in the context of DNA methylation. We found that dynamic CG methylation was dependent on Lsh in embryonic stem cells. Moreover, we demonstrate that ATP function is critical for de novo methylation at repeat sequences. The ATP binding site of Lsh is in part required to promote stable association of the DNA methyltransferase 3b with the repeat locus. By performing nucleosome occupancy assays, we found distinct nucleosome occupancy in KO ES cells compared to WT ES cells after differentiation. Nucleosome density was restored to wild-type level by re-expressing wild-type Lsh but not the ATP mutant in KO ES cells. Our results suggest that ATP-dependent nucleosome remodeling is the primary molecular function of Lsh, which may promote de novo methylation in differentiating ES cells.

Purpose-This paper explores whether the Western concept of servant leadership holds the same meaning in the public sector of the cross-cultural context of China and identify whether there is an alternative term in the Chinese language that closely relates to the concept of servant leadership Design/methodology/approach-An inductive approach is adopted based on critical incident technique, using open-ended survey to collect the data. Findings-We found that the concept of servant leadership holds parallel meaning in China, to that of the West and that we can describe the Chinese concept of servant leadership precisely as public servant leadership in the public sector and servant leadership in the non-public sector. We also report that when asked to characterize Chinese servant leadership in the public sector, the study respondents consider six types of servant leadership similar to the West but also three types of Chinese extended servant leadership. Originality/value-The paper is a first attempt to examine servant leadership in the public sector in China. It not only reports various forms of Chinese servant leadership orientation, but also compares and contrasts various servant leadership forms between China and the West, highlighting research gaps for future research within the context of the People's Republic of China (PRC) and the West.

Brain "inflammaging," a low-grade and chronic inflammation, is a major hallmark for aging-related neurodegenerative diseases. Here, by profiling H3K27ac and gene expression patterns in human and mouse brains, we found that age-related up-regulated (Age-Up) and down-regulated (Age-Down) genes have distinct H3K27ac patterns. Although both groups show promoter H3K27ac, the Age-Up genes, enriched for inflammation-related functions, are additionally marked by broad H3K27ac distribution over their gene bodies, which is progressively reduced during aging. Age-related gene expression changes can be predicted by gene-body H3K27ac level. Contrary to the presumed transcription activation function of promoter H3K27ac, we found that broad gene-body hyper H3K27ac suppresses overexpression of inflammaging genes. Altogether, our findings revealed opposite regulations by H3K27ac of Age-Up and Age-Down genes and a mode of broad gene-body H3K27ac in repressing transcription.