scholarly journals Characterization of the radiation desiccation response regulon of the radioresistant bacterium Deinococcus radiodurans by integrative genomic analyses.

2021 ◽  
Author(s):  
Nicolas Eugenie ◽  
Yvan Zivanovic ◽  
Gaelle Lelandais ◽  
Genevieve Coste ◽  
Claire Bouthier de la Tour ◽  
...  
Keyword(s):  
Deinococcus Radiodurans ◽  
Normal Growth ◽  
Growth Conditions ◽  
Rna Seq ◽  
Genome Wide ◽  
A Genome ◽  
Genomic Analyses ◽  
Number Of Genes ◽  
Wide Scale

Numerous genes are overexpressed in the radioresistant bacterium Deinococcus radiodurans after exposure to radiation or prolonged desiccation. The DdrO and IrrE proteins play a major role in regulating the expression of approximately predicted twenty of these genes. The transcriptional repressor DdrO blocks the expression of these genes under normal growth conditions. After exposure to genotoxic agents, the IrrE metalloprotease cleaves DdrO and relieves gene repression. Bioinformatic analyzes showed that this mechanism seems to be conserved in several species of Deinococcus, but many questions remain as such the number of genes regulated by DdrO. Here, by RNA-seq and CHiP-seq assays performed at a genome-wide scale coupled with bioinformatic analyses, we show that, the DdrO regulon in D. radiodurans includes many other genes than those previously described. These results thus pave the way to better understand the radioresistance mechanisms encoded by this bacterium.

scholarly journals Characterization of the Radiation Desiccation Response Regulon of the Radioresistant Bacterium Deinococcus radiodurans by Integrative Genomic Analyses

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2536
Author(s):  
Nicolas Eugénie ◽  
Yvan Zivanovic ◽  
Gaelle Lelandais ◽  
Geneviève Coste ◽  
Claire Bouthier de la Tour ◽  
...  
Keyword(s):  
Deinococcus Radiodurans ◽  
Transcriptional Repressor ◽  
Normal Growth ◽  
Growth Conditions ◽  
Rna Seq ◽  
Dna And Rna ◽  
Genomic Analyses ◽  
Number Of Genes ◽  
Genome Level

Numerous genes are overexpressed in the radioresistant bacterium Deinococcus radiodurans after exposure to radiation or prolonged desiccation. It was shown that the DdrO and IrrE proteins play a major role in regulating the expression of approximately twenty genes. The transcriptional repressor DdrO blocks the expression of these genes under normal growth conditions. After exposure to genotoxic agents, the IrrE metalloprotease cleaves DdrO and relieves gene repression. At present, many questions remain, such as the number of genes regulated by DdrO. Here, we present the first ChIP-seq analysis performed at the genome level in Deinococcus species coupled with RNA-seq, which was achieved in the presence or not of DdrO. We also resequenced our laboratory stock strain of D. radiodurans R1 ATCC 13939 to obtain an accurate reference for read alignments and gene expression quantifications. We highlighted genes that are directly under the control of this transcriptional repressor and showed that the DdrO regulon in D. radiodurans includes numerous other genes than those previously described, including DNA and RNA metabolism proteins. These results thus pave the way to better understand the radioresistance pathways encoded by this bacterium and to compare the stress-induced responses mediated by this pair of proteins in diverse bacteria.

Computational methods for annotation of plant regulatory non-coding RNAs using RNA-seq

2020 ◽  
Author(s):  
A T Vivek ◽  
Shailesh Kumar
Keyword(s):  
Computational Methods ◽  
High Throughput ◽  
Rna Seq ◽  
Physiological Mechanisms ◽  
Software Packages ◽  
Genome Wide ◽  
A Genome ◽  
Wide Scale ◽  
Plant Transcriptome ◽  
Non Coding Rnas

Abstract Plant transcriptome encompasses numerous endogenous, regulatory non-coding RNAs (ncRNAs) that play a major biological role in regulating key physiological mechanisms. While studies have shown that ncRNAs are extremely diverse and ubiquitous, the functions of the vast majority of ncRNAs are still unknown. With ever-increasing ncRNAs under study, it is essential to identify, categorize and annotate these ncRNAs on a genome-wide scale. The use of high-throughput RNA sequencing (RNA-seq) technologies provides a broader picture of the non-coding component of transcriptome, enabling the comprehensive identification and annotation of all major ncRNAs across samples. However, the detection of known and emerging class of ncRNAs from RNA-seq data demands complex computational methods owing to their unique as well as similar characteristics. Here, we discuss major plant endogenous, regulatory ncRNAs in an RNA sample followed by computational strategies applied to discover each class of ncRNAs using RNA-seq. We also provide a collection of relevant software packages and databases to present a comprehensive bioinformatics toolbox for plant ncRNA researchers. We assume that the discussions in this review will provide a rationale for the discovery of all major categories of plant ncRNAs.

scholarly journals Identification and characterization of circular RNAs in Ganoderma lucidum

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Junjie Shao ◽  
Liqiang Wang ◽  
Xinyue Liu ◽  
Meng Yang ◽  
Haimei Chen ◽  
...  
Keyword(s):  
Ganoderma Lucidum ◽  
Developmental Stages ◽  
Expression Profiles ◽  
Circular Rnas ◽  
Rna Seq ◽  
Polysaccharide Biosynthesis ◽  
Genome Wide ◽  
A Genome ◽  
Positive Correlations

Abstract Circular RNAs (circRNAs) play important roles in animals, plants, and fungi. However, no circRNAs have been reported in Ganoderma lucidum. Here, we carried out a genome-wide identification of the circRNAs in G.lucidum using RNA-Seq data, and analyzed their features. In total, 250 and 2193 circRNAs were identified from strand-specific RNA-seq data generated from the polyA(−) and polyA(−)/RNase R-treated libraries, respectively. Six of 131 (4.58%) predicted circRNAs were experimentally confirmed. Across three developmental stages, 731 exonic circRNAs (back spliced read counts ≥ 5) and their parent genes were further analyzed. CircRNAs were preferred originating from exons with flanking introns, and the lengths of the flanking intron were longer than those of the control introns. A total of 200 circRNAs were differentially expressed across the three developmental stages of G. lucidum. The expression profiles of 119 (16.3%) exonic circRNAs and their parent genes showed significant positive correlations (r ≥ 0.9, q < 0.01), whereas 226 (30.9%) exonic circRNAs and their parent genes exhibited significant negative correlations (r ≤ −0.9, q < 0.01), in which 53 parent genes are potentially involved in the transcriptional regulation, polysaccharide biosynthesis etc. Our results indicated that circRNAs are present in G. lucidum, with potentially important regulatory roles.

Abnormal demethylation and ectopic expression of leukotriene receptors genes LTB4R/LTB4R2 in breast cancer

2021 ◽  
pp. 21-30
Author(s):  
А.И. Калинкин ◽  
В.О. Сигин ◽  
М.В. Немцова ◽  
Е.Б. Кузнецова ◽  
Т.В. Кекеева ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Overall Survival ◽  
Bisulfite Sequencing ◽  
Cpg Island ◽  
Breast Tumors ◽  
Rna Seq ◽  
Genome Wide ◽  
A Genome ◽  
Leukotriene Receptor

Введение. Выявление и всесторонняя характеристика новых молекулярных маркеров злокачественных опухолей остаётся актуальной задачей онкологии. Ранее по результатам проведенного авторами широкогеномного скрининга дифференциального метилирования ДНК нормальных и опухолевых тканей молочной железы (МЖ) было выявлено аномальное деметилирование CpG-островка генов LTB4R/LTB4R2 в опухолях относительно нормы. Цель. Настоящее исследование посвящено молекулярной и клинической характеристике аномального деметилирования этого CpG-островка и экспрессии генов LTB4R/LTB4R2 при раке молочной железы (РМЖ). Методы. Для разведочного анализа использовали полученные авторами ранее результаты широкогеномного бисульфитного секвенирования Xmal-RRBS 110 образцов РМЖ и 6 образцов нормальной МЖ. В этой выборке был проведен сравнительный анализ уровней метилирования CpG-динуклеотидов в нормальной и опухолевой ткани 10 образцов трижды негативного (ТН) РМЖ с аномальным деметилированием LTB4R/LTB4R2 и 6 образцов нормальной МЖ с использованием критерия Манна-Уитни. Для подтверждения аномального деметилирования в образцах ТН РМЖ было использовано бисульфитное секвенирование по Сэнгеру. Для изучения корреляции между уровнями метилирования и экспрессии и для оценки прогностической значимости экспрессии генов LTB4R/LTB4R2 использовали данные 3 уровня по измерению метилирования с чипов Illumina HumanMethylation 450K, экспрессии RNA-seq, а также клинические характеристики 731 образцов из проекта TCGA-BRCA. Отличия между кривыми Каплана-Мейера сравнивали с использованием логранкового критерия. Результаты. Определено, что аномальное деметилирование CpG-островка генов LTB4R/LTB4R2 характерно для эпигеномного подтипа умеренно метилированных образцов ТН РМЖ. Определены дифференциально метилированные CpG-динуклеотиды CpG-островка генов LTB4R/LTB4R2; их дифференциальное метилирование подтверждено бисульфитным секвенированием по Сэнгеру. Установлена отрицательная корреляция между уровнем их метилирования и экспрессией генов LTB4R и LTB4R2. Показано, что общая выживаемость достоверно снижена в группе ТН РМЖ с высокой экспрессией LTB4R, а также в группе нормально-подобных опухолей МЖ с низкой экспрессией LTB4R и в группе LumB опухолей МЖ с низкой экспрессией LTB4R2. Различия показателей выживаемости позволяют рассматривать уровни экспрессии LTB4R/LTB4R2 как прогностический маркер при РМЖ, однако следует учитывать, что прогноз зависит от молекулярного подтипа опухоли. Это относится также к использованию уровней экспрессии LTB4R/LTB4R2 в качестве потенциального предиктивного маркера чувствительности таких опухолей к ингибиторам лейкотриеновых рецепторов при проведении клинических испытаний. Background. The identification and comprehensive characterization of new molecular markers of malignant tumors remains an urgent task of oncology. Earlier, according to the results of a genome-wide screening of differential DNA methylation of normal and tumor breast tissues, abnormal demethylation of the CpG island of LTB4R/LTB4R2 genes in tumors relative to norm was revealed. Aim. The present study focuses on the molecular and clinical characterization of abnormal demethylation of this CpG island and expression of the LTB4R/LTB4R2 genes in breast cancer (BC). Methods. For exploratory analysis, we used the previously obtained results of genome wide bisulfite sequencing of breast cancer (BC) and normal mammary gland samples. From this set, 10 samples of triple-negative (TN) breast cancer with abnormal LTB4R/LTB4R2 demethylation and 6 normal breast samples were selected, for which a comparative analysis of CpG methylation levels in cancer vs norm using the Mann-Whitney test was performed. Sanger bisulfite sequencing was used to confirm abnormal demethylation in TN BC samples. The analysis of the obtained electrophoregrams was carried out using the SeqBase software developed by the authors. To validate and assess the level of predictive significance of LTB4R/LTB4R2 gene expression, level 3 data were used to measure methylation from Illumina HumanMethylation 450K arrays, RNA-seq expression, as well as clinical characteristics for 731 samples from the TCGA-BRCA project. Kaplan-Meier curves were compared using a logrank test. Results. Abnormal demethylation of LTB4R/LTB4R2 genes in breast tumors was confirmed by Sanger sequencing. Among samples from the TCGA-BRCA project, a group of TN BC samples with low methylation of LTB4R/LTB4R2 genes was identified. Overall survival was significantly reduced in the TN breast cancer group with high LTB4R expression, as well as in the group of normal-like breast tumors with low LTB4R expression, and in the LumB group overall survival was significantly reduced when tumors demonstrated low LTB4R2 expression. Conclusions. Fine mapping of abnormal demethylation in individual CpG dinucleotides of the LTB4R/LTB4R2 genes will make it possible to design an effective PCR system that may potentially be used to define patients with TN breast cancer that would benefit from leukotriene receptor therapeutic inhibition. Different expression levels of LTB4R/LTB4R2 allow their use as a prognostic marker for breast cancer, but the prognosis directly depends on the molecular subtype of a tumor. This also applies to the use of different levels of LTB4R/LTB4R2 expression as a predictive marker of the sensitivity of such tumors to leukotriene receptor inhibitors in case they enter clinical trials.

scholarly journals Visualizing the periodic Ribo-seq reads with RiboPlotR

2019 ◽  
Author(s):  
Hsin-Yen Larry Wu ◽  
Polly Yingshan Hsu
Keyword(s):  
Mrna Translation ◽  
Open Reading Frames ◽  
Untranslated Regions ◽  
Rna Seq ◽  
Genome Wide ◽  
A Genome ◽  
Wide Scale ◽  
Non Coding Rnas ◽  
Reading Frames ◽  
Small Open Reading Frames

ABSTRACTBackgroundRibo-seq has revolutionized the study of mRNA translation in a genome-wide scale. High-quality Ribo-seq data display strong 3-nucleotide (nt) periodicity, which corresponds to translating ribosomes decipher three nucleotides each time. While the 3-nt periodicity has been widely used to study novel translation events and identify small open reading frames on presumed non-coding RNAs, tools which allow the visualization of those events remain underdeveloped.FindingsRiboPlotR is a visualization package written in R that presents both RNA-seq coverage and Ribo-seq reads for all annotated transcript isoforms in a context of a given gene. In particular, RiboPlotR plots Ribo-seq reads mapped in three reading frames using three colors for one isoform model at a time. Moreover, RiboPlotR shows Ribo-seq reads on upstream ORFs, 5’ and 3’ untranslated regions and introns, which is critical for observing new translation events and potential regulatory mechanisms.ConclusionsRiboPlotR is freely available (https://github.com/hsinyenwu/RiboPlotR) and allows the visualization of the translating features in Ribo-seq data.

scholarly journals Regulation of global transcription inE. coliby Rsd and 6S RNA

2016 ◽  
Author(s):  
Avantika Lal ◽  
Sandeep Krishna ◽  
Aswin Sai Narain Seshasayee
Keyword(s):  
Rna Polymerase ◽  
Sigma Factor ◽  
Global Gene Expression ◽  
Rna Seq ◽  
Genome Wide ◽  
A Genome ◽  
6S Rna ◽  
Wide Scale ◽  
Five Phases ◽  
First Time

ABSTRACTInEscherichia coli, the sigma factor σ70directs RNA polymerase to transcribe growth-related genes, while σ38directs transcription of stress response genes during stationary phase. Two molecules hypothesized to regulate RNA polymerase are the protein Rsd, which binds to σ70, and the non-coding 6S RNA which binds to the RNA polymerase- σ70holoenzyme. Despite multiple studies, the functions of Rsd and 6S RNA remain controversial. Here we use RNA-Seq in five phases of growth to elucidate their function on a genome-wide scale. We show for the first time that Rsd and 6S RNA facilitate σ38activity throughout bacterial growth, while 6S RNA also regulates widely different genes depending upon growth phase. We discover novel interactions between 6S RNA and Rsd and show widespread expression changes in a strain lacking both regulators. Finally, we present a mathematical model of transcription which highlights the crosstalk between Rsd and 6S RNA as a crucial factor in controlling sigma factor competition and global gene expression.

scholarly journals Altered Mediator dynamics during heat shock in budding yeast

2020 ◽  
Author(s):  
Debasish Sarkar ◽  
Z. Iris Zhu ◽  
Emily Paul ◽  
David Landsman ◽  
Randall H. Morse
Keyword(s):  
Heat Shock ◽  
Rna Polymerase Ii ◽  
Growth Conditions ◽  
Proximal Promoter ◽  
Promoter Regions ◽  
Pol Ii ◽  
Genome Wide ◽  
A Genome ◽  
Similar Dependence ◽  
Wide Scale

AbstractThe Mediator complex is central to transcription by RNA polymerase II (Pol II) in eukaryotes. In yeast, Mediator is recruited by activators via its tail module and then facilitates assembly of the pre-initiation complex (PIC), including Pol II, setting the stage for productive transcription. Mediator occupies proximal promoter regions only transiently prior to Pol II escape; interruption of the transcription cycle by inactivation or depletion of Kin28 inhibits Pol II escape and stabilizes Mediator occupancy at promoters. However, whether Mediator occupancy and dynamics differ for gene cohorts induced by stress or alternative growth conditions has not been examined on a genome-wide scale. Here we investigate Mediator occupancy following heat shock or CdCl2 induction, with or without depletion of Kin28. We find that Pol II occupancy exhibits similar dependence on Mediator under normal and heat shock conditions; however, Mediator occupancy does not increase upon Kin28 depletion at most genes active during heat shock, indicating altered dynamics. Furthermore, Mediator occupancy persists at genes repressed by heat shock or CdCl2 induction and exhibits peaks upstream of the proximal promoter whether or not Kin28 is depleted, suggesting that Mediator is recruited by activators but is unable to engage PIC components at these repressed targets. Finally, we show a reduced dependence on PIC components for Mediator occupancy at promoters after heat shock, further supporting an altered dynamics or stronger engagement with activators under these conditions.

scholarly journals Genome-Wide Identification and Characterization of Hsf and Hsp Gene Families and Gene Expression Analysis under Heat Stress in Eggplant (Solanum melongema L.)

Horticulturae ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 149
Author(s):  
Chao Gong ◽  
Qiangqiang Pang ◽  
Zhiliang Li ◽  
Zhenxing Li ◽  
Riyuan Chen ◽  
...  
Keyword(s):  
Heat Stress ◽  
Gene Families ◽  
High Temperature Stress ◽  
Pcr Analysis ◽  
Rna Seq ◽  
Genome Wide ◽  
Motif Composition ◽  
Hsp Genes ◽  
Identification And Characterization

Under high temperature stress, a large number of proteins in plant cells will be denatured and inactivated. Meanwhile Hsfs and Hsps will be quickly induced to remove denatured proteins, so as to avoid programmed cell death, thus enhancing the thermotolerance of plants. Here, a comprehensive identification and analysis of the Hsf and Hsp gene families in eggplant under heat stress was performed. A total of 24 Hsf-like genes and 117 Hsp-like genes were identified from the eggplant genome using the interolog from Arabidopsis. The gene structure and motif composition of Hsf and Hsp genes were relatively conserved in each subfamily in eggplant. RNA-seq data and qRT-PCR analysis showed that the expressions of most eggplant Hsf and Hsp genes were increased upon exposure to heat stress, especially in thermotolerant line. The comprehensive analysis indicated that different sets of SmHsps genes were involved downstream of particular SmHsfs genes. These results provided a basis for revealing the roles of SmHsps and SmHsp for thermotolerance in eggplant, which may potentially be useful for understanding the thermotolerance mechanism involving SmHsps and SmHsp in eggplant.

scholarly journals F-Box Genes in the Wheat Genome and Expression Profiling in Wheat at Different Developmental Stages

Genes ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1154
Author(s):  
Min Jeong Hong ◽  
Jin-Baek Kim ◽  
Yong Weon Seo ◽  
Dae Yeon Kim
Keyword(s):  
Developmental Stages ◽  
Brachypodium Distachyon ◽  
Triticum Aestivum L ◽  
Wheat Genome ◽  
Post Translational Modification ◽  
Genome Wide ◽  
A Genome ◽  
High Sequence Homology ◽  
Wide Scale

Genes of the F-box family play specific roles in protein degradation by post-translational modification in several biological processes, including flowering, the regulation of circadian rhythms, photomorphogenesis, seed development, leaf senescence, and hormone signaling. F-box genes have not been previously investigated on a genome-wide scale; however, the establishment of the wheat (Triticum aestivum L.) reference genome sequence enabled a genome-based examination of the F-box genes to be conducted in the present study. In total, 1796 F-box genes were detected in the wheat genome and classified into various subgroups based on their functional C-terminal domain. The F-box genes were distributed among 21 chromosomes and most showed high sequence homology with F-box genes located on the homoeologous chromosomes because of allohexaploidy in the wheat genome. Additionally, a synteny analysis of wheat F-box genes was conducted in rice and Brachypodium distachyon. Transcriptome analysis during various wheat developmental stages and expression analysis by quantitative real-time PCR revealed that some F-box genes were specifically expressed in the vegetative and/or seed developmental stages. A genome-based examination and classification of F-box genes provide an opportunity to elucidate the biological functions of F-box genes in wheat.

scholarly journals Genome-wide mapping of unexplored essential regions in the Saccharomyces cerevisiae genome: evidence for hidden synthetic lethal combinations in a genetic interaction network

2014 ◽  
Vol 42 (15) ◽  
pp. 9838-9853 ◽  
Author(s):  
Saeed Kaboli ◽  
Takuya Yamakawa ◽  
Keisuke Sunada ◽  
Tao Takagaki ◽  
Yu Sasano ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Genetic Interaction ◽  
Interaction Network ◽  
Essential Genes ◽  
Genetic Interactions ◽  
Lethal Gene ◽  
Synthetic Lethal ◽  
Genome Wide ◽  
A Genome ◽  
Wide Scale

Abstract Despite systematic approaches to mapping networks of genetic interactions in Saccharomyces cerevisiae, exploration of genetic interactions on a genome-wide scale has been limited. The S. cerevisiae haploid genome has 110 regions that are longer than 10 kb but harbor only non-essential genes. Here, we attempted to delete these regions by PCR-mediated chromosomal deletion technology (PCD), which enables chromosomal segments to be deleted by a one-step transformation. Thirty-three of the 110 regions could be deleted, but the remaining 77 regions could not. To determine whether the 77 undeletable regions are essential, we successfully converted 67 of them to mini-chromosomes marked with URA3 using PCR-mediated chromosome splitting technology and conducted a mitotic loss assay of the mini-chromosomes. Fifty-six of the 67 regions were found to be essential for cell growth, and 49 of these carried co-lethal gene pair(s) that were not previously been detected by synthetic genetic array analysis. This result implies that regions harboring only non-essential genes contain unidentified synthetic lethal combinations at an unexpectedly high frequency, revealing a novel landscape of genetic interactions in the S. cerevisiae genome. Furthermore, this study indicates that segmental deletion might be exploited for not only revealing genome function but also breeding stress-tolerant strains.

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