Background Owing to the rapid advances in DNA sequencing technologies, whole genome from more and more species are becoming available at increasing pace. For whole-genome analysis, idiograms provide a very popular, intuitive and effective way to map and visualize the genome-wide information, such as GC content, gene and repeat density, DNA methylation distribution, genomic synteny, etc. However, most available software programs and web servers are available only for a few model species, such as human, mouse and fly, or have limited application scenarios. As more and more non-model species are sequenced with chromosome-level assembly being available, tools that can generate idiograms for a broad range of species and be capable of visualizing more data types are needed to help better understanding fundamental genome characteristics. Results The R package RIdeogram allows users to build high-quality idiograms of any species of interest. It can map continuous and discrete genome-wide data on the idiograms and visualize them in a heat map and track labels, respectively. Conclusion The visualization of genome-wide data mapping and comparison allow users to quickly establish a clear impression of the chromosomal distribution pattern, thus making RIdeogram a useful tool for any researchers working with omics.

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Glycolysis is critical for cancer stem cell reprogramming; however, the underlying regulatory mechanisms remain elusive. Here, we show that pyruvate dehydrogenase kinase 1 (PDK1) is enriched in breast cancer stem cells (BCSCs), whereas depletion of PDK1 remarkably diminishes ALDH+ subpopulations, decreases stemness-related transcriptional factor expression, and inhibits sphere-formation ability and tumor growth. Conversely, high levels of PDK1 enhance BCSC properties and are correlated with poor overall survival. In mouse xenograft tumor, PDK1 is accumulated in hypoxic regions and activates glycolysis to promote stem-like traits. Moreover, through screening hypoxia-related long non-coding RNAs (lncRNAs) in PDK1-positive tissue, we find that lncRNA H19 is responsible for glycolysis and BCSC maintenance. Furthermore, H19 knockdown decreases PDK1 expression in hypoxia, and ablation of PDK1 counteracts H19-mediated glycolysis and self-renewal ability in vitro and in vivo. Accordingly, H19 and PDK1 expression exhibits strong correlations in primary breast carcinomas. H19 acting as a competitive endogenous RNA sequesters miRNA let-7 to release Hypoxia-inducible factor 1α, leading to an increase in PDK1 expression. Lastly, aspirin markedly attenuates glycolysis and cancer stem-like characteristics by suppressing both H19 and PDK1. Thus, these novel findings demonstrate that the glycolysis gatekeeper PDK1 has a critical role in BCSC reprogramming and provides a potential therapeutic strategy for breast malignancy.

Salinity and alkalinity are the two main environmental factors that limit rice production. Better understanding of the mechanisms responsible for salinity and alkaline stress tolerance would allow researchers to modify rice to increase its resistance to salinity and alkaline stress. MicroRNAs (miRNAs) are ~21-nucleotide RNAs that are ubiquitous regulators of gene expression in eukaryotic organisms. Some miRNAs acts as an important endogenous regulator in plant responses to abiotic stressors. miR393 is a conservative miRNA family that occurs in a variety of different plants. The two members of the miR393 family found in rice are named osa-MIR393 and osa-MIR393b. We found that the osa-MIR393 expression level changed under salinity and alkaline stress, whereas that of osa-MIR393b did not. Target genes of osa-MIR393 were predicted, and some of these putative targets are abiotic related genes. Furthermore, we generated transgenic rice and Arabidopsis thaliana that over-expressed osa-MIR393, and the phenotype analysis showed that these transgenic plants were more sensitive to salt and alkali treatment compared to wild-type plants. These results illustrate that over-expression of osa-MIR393 can negatively regulate rice salt-alkali stress tolerance.

Salt and alkali stress are two of the main environmental factors limiting rice production. Thus, understanding the mechanisms of salinity and alkali stress tolerance is necessary to modify rice to increase its resistance to salinity and alkaline stress. MicroRNAs (miRNAs) are approximately 21-nucleotide RNAs that are ubiquitous regulators of gene expression in eukaryotic organisms. In plants, miRNAs constitute one of five classes of small RNAs that function primarily as negative regulators for gene expression at the posttranscriptional level. Several plant miRNAs, such as miR396, play vital roles in plant growth, development and resistance to stresses. In this study, we identified osa-MIR396c, which shows dramatic transcript change under salt and alkali stress conditions in Oryza sativa. We designed an experiment to detect miRNA-target interaction and demonstrated that several transcription factors related to growth, development, and stress tolerance are targeted by osa-MIR396c. Transgenic rice and Arabidopsis thaliana plants constitutively over-expressing osa-MIR396c showed reduced salt and alkali stress tolerance compared to that of wild-type plants. Overall, this study further established a link between salt and alkali stress and osa-MIR396c in rice.