scholarly journals The multi-speed genome ofFusarium oxysporumreveals association of histone modifications with sequence divergence and footprints of past horizontal chromosome transfer events

2018 ◽  
Author(s):  
Like Fokkens ◽  
Shermineh Shahi ◽  
Lanelle R. Connolly ◽  
Remco Stam ◽  
Sarah M. Schmidt ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Histone Modifications ◽  
Fungal Infections ◽  
Sequence Similarity ◽  
Genome Structure ◽  
Histone H3 ◽  
Sequence Divergence ◽  
Chromosome Transfer ◽  
A Genome ◽  
Accessory Chromosomes

AbstractFusarium oxysporumis an economically important pathogen causing wilting or rotting disease symptoms in a large number of crops. It is proposed to have a structured, “two-speed” genome: i.e. regions containing genes involved in pathogenicity cluster with transposons on separate accessory chromosomes. This is hypothesized to enhance evolvability. Given the continuum of adaptation of all the genes encoded in a genome, however, one would expect a more complex genome structure. By comparing the genome of reference strain Fol4287 to those of 58 otherFusarium oxysporumstrains, we found that some Fol4287 accessory chromosomes are lineage-specific, while others occur in multiple lineages with very high sequence similarity - but only in strains that infect the same host as Fol4287. This indicates that horizontal chromosome transfer has been instrumental in past host-switches. Unexpectedly, we found that the sequence of the three smallest core chromosomes (Chr. 11, 12 and 13) is more divergent than that of the other core chromosomes. Moreover, these chromosomes are enriched in genes involved in metabolism and transport and genes that are differentially regulated during infection. Interestingly, these chromosomes are –like the accessory chromosomes– marked by histone H3 lysine 27 trimethylation (H3K27me3) and depleted in histone H3 lysine 4 dimethylation (H3K4me2). Detailed genomic analyses revealed a complex, “multi-speed genome” structure inFusarium oxysporum. We found a strong association of H3K27me3 with elevated levels of sequence divergence that is independent of the presence of repetitive elements. This provides new leads into how clustering of genes evolving at similar rates could increase evolvability.Author summaryFungi that cause disease on plants are an increasingly important threat to food security. New fungal diseases emerge regularly. The agricultural industry makes large investments to breed crops that are resistant to fungal infections, yet rapid adaptation enables fungal pathogens to overcome this resistance within a few years or decades. It has been proposed that genome ‘compartmentalization’ of plant pathogenic fungi, in which infection-related genes are clustered with transposable elements (or ‘jumping genes’) into separate, fast-evolving regions, enhances their adaptivity. Here, we aimed to shed light on the possible interplay between genome organization and adaptation. We measured differences in sequence divergence and dispensability between and within individual chromosomes of the important plant pathogenFusarium oxysporum. Based on these differences we defined four distinct chromosomal categories. We then mapped histone modifications and gene expression levels under different conditions for these four categories. We found a ‘division of labor’ between chromosomes, where some are ‘pathogenicity chromosomes’ - specialized towards infection of a specific host, while others are enriched in genes involved in more generic infection-related processes. Moreover, we confirmed that horizontal transfer of pathogenicity chromosomes likely plays an important role in gain of pathogenicity. Finally, we found that a specific histone modification is associated with increased sequence divergence.

scholarly journals Complete Genome sequence of a new variant of jujube mosaic-associated virus isolated from jujube (Ziziphus jujuba Mill.) grown at Aksu in Xinjiang of China

2021 ◽  
Author(s):  
Jianyu Bai ◽  
Baojun Liu ◽  
Guoxin Zhang ◽  
Aixing Gu ◽  
Danbo Song ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Sequence Similarity ◽  
Genome Structure ◽  
Rnase H ◽  
Amino Acid Sequence Similarity ◽  
Coding Region ◽  
A Genome ◽  
New Variant

Abstract This work reports the discovery and the complete genome sequence of a novel member of the genus Badnavirus in the family Caulimoviridae from a Chinese jujube tree of known variety which grown in Aksu, Xinjiang, China. The symptoms of jujube leaves infected by the virus showed mosaic and malformation, and round chlorotic spots on infected fruits. The genome of this virus is a circular double-stranded DNA, which has the length of 7086 nt and has a genome structure similar to the one reported for jujube mosaic-associated virus (JuMaV), with five open reading frames (ORFs). High nucleotide and amino acid sequence similarity were seen between JuMaV and the new virus, and the nucleotide (NT) difference of the genome was greater than 20% in the RT/ Rnase H coding region of ORF3. Consequently, the virus was identified a new variant of JuMaV, and propose the name as jujube mosaic-associated virus A (JuMaVA).

scholarly journals RRE-Finder: A Genome-Mining Tool for Class-Independent RiPP Discovery

2020 ◽  
Author(s):  
Alexander M. Kloosterman ◽  
Kyle E. Shelton ◽  
Gilles P. van Wezel ◽  
Marnix H. Medema ◽  
Douglas A. Mitchell
Keyword(s):  
Sequence Similarity ◽  
Genome Mining ◽  
Sequence Divergence ◽  
High Sensitivity ◽  
Gene Clusters ◽  
Protein Domain ◽  
Post Translational Modification ◽  
Protein Database ◽  
Recognition Element ◽  
A Genome

AbstractNearly half of the classes of natural products known as ribosomally synthesized and post-translationally modified peptides (RiPPs) are reliant on a protein domain called the RiPP recognition element (RRE) for peptide maturation. The RRE binds specifically to a linear precursor peptide and directs the post-translational modification enzymes to their substrate. Given its prevalence across various types of RiPP biosynthetic gene clusters (BGCs), the RRE could theoretically be used as a bioinformatic handle to identify novel classes of RiPPs. In addition, due to the high affinity and specificity of most RRE:precursor peptide complexes, a thorough understanding of the RRE domain could be exploited for biotechnological applications. However, sequence divergence of the RRE domain across RiPP classes has precluded automated identification of RREs based solely on sequence similarity. Here, we introduce RRE-Finder, a novel tool for identifying RRE domains with high sensitivity. RRE-Finder can be used in “precision” mode to confidently identify RREs in a class-specific manner or in “exploratory” mode, which was designed to assist in the discovery of novel RiPP classes. RRE-Finder operating in precision mode on the UniProtKB protein database retrieved over 30,000 high-confidence RREs spanning all characterized RRE-dependent RiPP classes, as well as several yet-uncharacterized RiPP, putatively novel gene cluster architectures that will require future experimental work. Finally, RRE-Finder was used in precision mode to explore a possible evolutionary origin of the RRE domain. Altogether, RRE-Finder provides a powerful new method to probe RiPP biosynthetic diversity and delivers a rich dataset of RRE sequences that will provide a foundation for deeper biochemical studies into this intriguing and versatile protein domain.

scholarly journals Epigenetic Regulation of MicroRNA Clusters and Families during Tumor Development

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1333
Author(s):  
Jana Gregorova ◽  
Petra Vychytilova-Faltejskova ◽  
Sabina Sevcikova
Keyword(s):  
Histone Modifications ◽  
Sequence Similarity ◽  
Tumor Development ◽  
Hematologic Malignancies ◽  
Seed Region ◽  
Cancer Therapies ◽  
Rna Molecules ◽  
Physiological Processes ◽  
Close Relationship ◽  
Aberrant Dna Methylation

MicroRNAs are small non-coding single-stranded RNA molecules regulating gene expression on a posttranscriptional level based on the seed sequence similarity. They are frequently clustered; thus, they are either simultaneously transcribed into a single polycistronic transcript or they may be transcribed independently. Importantly, microRNA families that contain the same seed region and thus target related signaling proteins, may be localized in one or more clusters, which are in a close relationship. MicroRNAs are involved in basic physiological processes, and their deregulation is associated with the origin of various pathologies, including solid tumors or hematologic malignancies. Recently, the interplay between the expression of microRNA clusters and families and epigenetic machinery was described, indicating aberrant DNA methylation or histone modifications as major mechanisms responsible for microRNA deregulation during cancerogenesis. In this review, the most studied microRNA clusters and families affected by hyper- or hypomethylation as well as by histone modifications are presented with the focus on particular mechanisms. Finally, the diagnostic and prognostic potential of microRNA clusters and families is discussed together with technologies currently used for epigenetic-based cancer therapies.

scholarly journals The chromatin-binding protein HMGN3 stimulates histone acetylation and transcription across the Glyt1 gene

2012 ◽  
Vol 442 (3) ◽  
pp. 495-505 ◽  
Author(s):  
Gráinne Barkess ◽  
Yuri Postnikov ◽  
Chrisanne D. Campos ◽  
Shivam Mishra ◽  
Gokula Mohan ◽  
...  
Keyword(s):  
Histone Modifications ◽  
Splice Variants ◽  
Binding Protein ◽  
Histone H3 ◽  
Camp Response Element Binding ◽  
Element Binding Protein ◽  
H3k14 Acetylation ◽  
H3 Acetylation

HMGNs are nucleosome-binding proteins that alter the pattern of histone modifications and modulate the binding of linker histones to chromatin. The HMGN3 family member exists as two splice forms, HMGN3a which is full-length and HMGN3b which lacks the C-terminal RD (regulatory domain). In the present study, we have used the Glyt1 (glycine transporter 1) gene as a model system to investigate where HMGN proteins are bound across the locus in vivo, and to study how the two HMGN3 splice variants affect histone modifications and gene expression. We demonstrate that HMGN1, HMGN2, HMGN3a and HMGN3b are bound across the Glyt1 gene locus and surrounding regions, and are not enriched more highly at the promoter or putative enhancer. We conclude that the peaks of H3K4me3 (trimethylated Lys4 of histone H3) and H3K9ac (acetylated Lys9 of histone H3) at the active Glyt1a promoter do not play a major role in recruiting HMGN proteins. HMGN3a/b binding leads to increased H3K14 (Lys14 of histone H3) acetylation and stimulates Glyt1a expression, but does not alter the levels of H3K4me3 or H3K9ac enrichment. Acetylation assays show that HMGN3a stimulates the ability of PCAF [p300/CREB (cAMP-response-element-binding protein)-binding protein-associated factor] to acetylate nucleosomal H3 in vitro, whereas HMGN3b does not. We propose a model where HMGN3a/b-stimulated H3K14 acetylation across the bodies of large genes such as Glyt1 can lead to more efficient transcription elongation and increased mRNA production.

Nonomuraea montanisoli sp. nov., isolated from mountain forest soil

2021 ◽  
Author(s):  
Suchart Chanama ◽  
Chanwit Suriyachadkun ◽  
Manee Chanama
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Related Species ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
Mountain Forest ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
A Genome

A novel actinomycete, strain SMC 257T, was isolated from a soil sample collected from mountain forest, Nan Province, Thailand. Strain SMC 257T formed tightly closed spiral spore chains on aerial mycelia. A polyphasic approach was used for the taxonomic study of this strain. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SMC 257T belonged to the genus Nonomuraea , and the closest phylogenetically related species were Nonomuraea roseoviolacea subsp. carminata JCM 9946T (98.9 % 16S rRNA gene sequence similarity), Nonomuraea rhodomycinica TBRC 6557T (98.4 %), and Nonomuraea roseoviolacea subsp. roseoviolacea JCM 3145T (98.3 %). Genome sequencing revealed a genome size of 9.76 Mbp and a G+C content of 72.3 mol%. The genome average nucleotide identity (ANI) and the digital DNA–DNA hybridization (dDDH) values that distinguished this novel strain from its closest related species were species boundary of 95–96 % and 70 %, respectively. The cell wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars were glucose, ribose, madurose and mannose. The major menaquinone was MK-9(H4). The polar lipid profile consisted of phosphatidylethanolamine, hydroxyphosphatidylethanolamine, lysophosphatidylethanolamine, diphosphatidylglycerol, N-phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides. The predominant cellular fatty acids were C17 : 0 10-methyl and iso-C16 : 0. Based on comparative analysis of phenotypic, chemotaxonomic and genotypic data, strain SMC 257T is considered to represent a novel species of the genus Nonomuraea , for which the name Nonomuraea montanisoli is proposed. The type strain is SMC 257T (=TBRC 13065T=NBRC 114772T).

scholarly journals Dynamic Methylation Changes of DNA and H3K4 by RG108 Improve Epigenetic Reprogramming of Somatic Cell Nuclear Transfer Embryos in Pigs

2018 ◽  
Vol 50 (4) ◽  
pp. 1376-1397 ◽  
Author(s):  
Yanhui Zhai ◽  
Zhiren Zhang ◽  
Hao Yu ◽  
Li Su ◽  
Gang Yao ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Somatic Cell ◽  
Histone Modifications ◽  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
Histone H3 ◽  
Dna Demethylation ◽  
Epigenetic Reprogramming ◽  
Expression Levels ◽  
Fetal Fibroblasts

Background/Aims: DNA methylation and histone modifications are essential epigenetic marks that can significantly affect the mammalian somatic cell nuclear transfer (SCNT) embryo development. However, the mechanisms by which the DNA methylation affects the epigenetic reprogramming have not been fully elucidated. Methods: In our study, we used quantitative polymerase chain reaction (qPCR), Western blotting, immunofluorescence staining (IF) and sodium bisulfite genomic sequencing to examine the effects of RG108, a DNA methyltransferase inhibitor (DNMTi), on the dynamic pattern of DNA methylation and histone modifications in porcine SCNT embryos and investigate the mechanism by which the epigenome status of donor cells’ affects SCNT embryos development and the crosstalk between epigenetic signals. Results: Our results showed that active DNA demethylation was enhanced by the significantly improving expression levels of TET1, TET2, TET3 and 5hmC, and passive DNA demethylation was promoted by the remarkably inhibitory expression levels of DNMT1, DNMT3A and 5mC in embryos constructed from the fetal fibroblasts (FFs) treated with RG108 (RG-SCNT embryos) compared to the levels in embryos from control FFs (FF-SCNT embryos). The signal intensity of histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 9 acetylation (H3K9Ac) was significantly increased and the expression levels of H3K4 methyltransferases were more than 2-fold higher expression in RG-SCNT embryos. RG-SCNT embryos had significantly higher cleavage and blastocyst rates (69.3±1.4%, and 24.72±2.3%, respectively) than FF-SCNT embryos (60.1±2.4% and 18.38±1.9%, respectively). Conclusion: Dynamic changes in DNA methylation caused by RG108 result in dynamic alterations in the patterns of H3K4me3, H3K9Ac and histone H3 lysine 9 trimethylation (H3K9me3), which leads to the activation of embryonic genome and epigenetic modification enzymes associated with H3K4 methylation, and contributes to reconstructing normal epigenetic modifications and improving the developmental efficiency of porcine SCNT embryos.

scholarly journals Assessing universality of DNA barcoding in geographically isolated selected desert medicinal species of Fabaceae and Poaceae

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4499 ◽  
Author(s):  
Aisha Tahir ◽  
Fatma Hussain ◽  
Nisar Ahmed ◽  
Abdolbaset Ghorbani ◽  
Amer Jamil
Keyword(s):  
Dna Barcoding ◽  
Species Identification ◽  
Phylogenetic Trees ◽  
Sequence Similarity ◽  
Sequence Divergence ◽  
Species Level ◽  
Practical Implementation ◽  
Medicinal Species ◽  
Level Identification ◽  
Geographically Isolated

In pursuit of developing fast and accurate species-level molecular identification methods, we tested six DNA barcodes, namely ITS2, matK, rbcLa, ITS2+matK, ITS2+rbcLa, matK+rbcLa and ITS2+matK+rbcLa, for their capacity to identify frequently consumed but geographically isolated medicinal species of Fabaceae and Poaceae indigenous to the desert of Cholistan. Data were analysed by BLASTn sequence similarity, pairwise sequence divergence in TAXONDNA, and phylogenetic (neighbour-joining and maximum-likelihood trees) methods. Comparison of six barcode regions showed that ITS2 has the highest number of variable sites (209/360) for tested Fabaceae and (106/365) Poaceae species, the highest species-level identification (40%) in BLASTn procedure, distinct DNA barcoding gap, 100% correct species identification in BM and BCM functions of TAXONDNA, and clear cladding pattern with high nodal support in phylogenetic trees in both families. ITS2+matK+rbcLa followed ITS2 in its species-level identification capacity. The study was concluded with advocating the DNA barcoding as an effective tool for species identification and ITS2 as the best barcode region in identifying medicinal species of Fabaceae and Poaceae. Current research has practical implementation potential in the fields of pharmaco-vigilance, trade of medicinal plants and biodiversity conservation.

scholarly journals Hansschlegelia quercus sp. nov., a novel methylotrophic bacterium isolated from oak buds

2020 ◽  
Vol 70 (8) ◽  
pp. 4646-4652 ◽  
Author(s):  
Nadezhda V. Agafonova ◽  
Elena N. Kaparullina ◽  
Denis S. Grouzdev ◽  
Nina V. Doronina
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Sequence Similarity ◽  
Methylotrophic Bacterium ◽  
Rrna Gene ◽  
Methylotrophic Bacteria ◽  
Content Type ◽  
Link Type ◽  
A Genome

Novel aerobic, restricted facultatively methylotrophic bacteria were isolated from buds of English oak (Quercus robur L.; strain DubT) and northern red oak (Quercus rubra L.; strain KrD). The isolates were Gram-negative, asporogenous, motile short rods that multiplied by binary fisson. They utilized methanol, methylamine and a few polycarbon compounds as carbon and energy sources. Optimal growth occurred at 25 °C and pH 7.5. The dominant phospholipids were phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol and phoshatidylglycerol. The major cellular fatty acids of cells were C18 : 1 ω7c, 11-methyl C18 : 1 ω7c and C16 : 0. The major ubiquinone was Q-10. Analysis of 16S rRNA gene sequences showed that the strains were closely related to the members of the genus Hansschlegelia : Hansschlegelia zhihuaiae S113T(97.5–98.0 %), Hansschlegelia plantiphila S1T (97.4–97.6 %) and Hansschlegelia beijingensis PG04T(97.0–97.2 %). The 16S rRNA gene sequence similarity between strains DubT and KrD was 99.7 %, and the DNA–DNA hybridization (DDH) result between the strains was 85 %. The ANI and the DDH values between strain DubT and H. zhihuaiae S113T were 80.1 and 21.5  %, respectively. Genome sequencing of the strain DubT revealed a genome size of 3.57 Mbp and a G+C content of 67.0 mol%. Based on the results of the phenotypic, chemotaxonomic and genotypic analyses, it is proposed that the isolates be assigned to the genus Hansschlegelia as Hansschlegelia quercus sp. nov. with the type strain DubT (=VKM B-3284T=CCUG 73648T=JCM 33463T).

scholarly journals The Two Drosophila Telomeric Transposable Elements Have Very Different Patterns of Transcription

1999 ◽  
Vol 19 (1) ◽  
pp. 873-881 ◽  
Author(s):  
O. N. Danilevskaya ◽  
K. L. Traverse ◽  
N. C. Hogan ◽  
P. G. DeBaryshe ◽  
M. L. Pardue
Keyword(s):  
Transposable Elements ◽  
Sequence Similarity ◽  
Sequence Divergence ◽  
Full Length ◽  
Coding Region ◽  
Free Standing ◽  
Reading Frame ◽  
Sequence Organization ◽  
Sense Strand ◽  
Cell Fractions

ABSTRACT The transposable elements HeT-A and TARTconstitute the telomeres of Drosophila chromosomes. Both are non-long terminal repeat (LTR) retrotransposons, sharing the remarkable property of transposing only to chromosome ends. In addition, strong sequence similarity of their gag proteins indicates that these coding regions share a common ancestor. These findings led to the assumption that HeT-A andTART are closely related. However, we now find that these elements produce quite different sets of transcripts. HeT-Aproduces only sense-strand transcripts of the full-length element, whereas TART produces both sense and antisense full-length RNAs, with antisense transcripts in more than 10-fold excess over sense RNA. In addition, features of TART sequence organization resemble those of a subclass of non-LTR elements characterized by unequal terminal repeats. Thus, the ancestral gag sequence appears to have become incorporated in two different types of elements, possibly with different functions in the telomere. HeT-Atranscripts are found in both nuclear and cytoplasmic cell fractions, consistent with roles as both mRNA and transposition template. In contrast, both sense and antisense TART transcripts are almost entirely concentrated in nuclear fractions. Also,TART open reading frame 2 probes detect a cytoplasmic mRNA for reverse transcriptase (RT), with no similarity to TARTsequence 5′ or 3′ of the RT coding region. This RNA could be a processed TART transcript or the product of a “free-standing” RT gene. Either origin would be novel. The distinctive transcription patterns of both HeT-A andTART are conserved in Drosophila yakuba, despite significant sequence divergence. The conservation argues that these sets of transcripts are important to the function(s) ofHeT-A and TART.

scholarly journals Transcription Factors Encoded on Core and Accessory Chromosomes of Fusarium oxysporum Induce Expression of Effector Genes

PLoS Genetics ◽  
2016 ◽  
Vol 12 (11) ◽  
pp. e1006401 ◽  
Author(s):  
H. Charlotte van der Does ◽  
Like Fokkens ◽  
Ally Yang ◽  
Sarah M. Schmidt ◽  
Léon Langereis ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Fusarium Oxysporum ◽  
Effector Genes ◽  
Accessory Chromosomes
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