scholarly journals An improved assembly and annotation of the allohexaploid wheat genome identifies complete families of agronomic genes and provides genomic evidence for chromosomal translocations

2016 ◽  
Author(s):  
Bernardo J. Clavijo ◽  
Luca Venturini ◽  
Christian Schudoma ◽  
Gonzalo Garcia Accinelli ◽  
Gemy Kaithakottil ◽  
...  

Advances in genome sequencing and assembly technologies are generating many high quality genome sequences, but assemblies of large, repeat-rich polyploid genomes, such as that of bread wheat, remain fragmented and incomplete. We have generated a new wheat whole-genome shotgun sequence assembly using a combination of optimised data types and an assembly algorithm designed to deal with large and complex genomes. The new assembly represents more than 78% of the genome with a scaffold N50 of 88.8kbp that has a high fidelity to the input data. Our new annotation combines strand-specific Illumina RNAseq and PacBio full-length cDNAs to identify 104,091 high confidence protein-coding genes and 10,156 non-coding RNA genes. We confirmed three known and identified one novel genome rearrangements. Our approach enables the rapid and scalable assembly of wheat genomes, the identification of structural variants, and the definition of complete gene models, all powerful resources for trait analysis and breeding of this key global crop. [Supplemental material is available for this article.]

2021 ◽  
Vol 11 (8) ◽  
pp. 1306-1312
Author(s):  
Li Song ◽  
Ningchao Du ◽  
Haitao Luo ◽  
Furong Li

This study aimed to identify the association of protein coding and long non coding RNA genes with immunotherapy response in melanoma. Based on RNA sequencing data of melanoma specimens, the expression levels of protein coding and long non coding RNA genes were calculated using the Kallisto RNA-seq quantification method, and differently expressed genes were detected using the DESeq2 method. Cox proportional hazards regression was used to evaluate the effects of gene expression on survival. According to the clinical data of 14 patients with drug response and 11 patients without drug response, 18 protein coding genes and 14 long non coding RNAs showed differential expressions (multiple of difference > 2 and P < 0.01 after correction), among which the coding genes of differential expression were significantly enriched through the process of cell adhesion (P < 0.01). The results of survival analysis showed that 18 coding genes and 14 long non coding RNA genes had significant effects on patient survival (P < 0.01). In this study, magnetic nanoparticles can be used to extract genomic DNA and total RNA due to their paramagnetism and biocompatibility, then transcriptome high-throughput sequencing was performed. The method has the advantages of removing dangerous reagents such as phenol and chloroform, replacing inorganic coating such as silica with organic oil, and shortening reaction time. Protein coding and long non coding RNA genes as well as magnetic nanoparticles may serve as potential cancer immune biomarker targets for developing future oncological treatments.


2021 ◽  
Author(s):  
Phougeishangbam Rolish Singh ◽  
Bart van de Vossenberg ◽  
Katarzynar Rybarczyk-Mydłowska3 ◽  
Magdalena Kowalewska-Groszkowska ◽  
Wim Bert ◽  
...  

Rotylenchus is a widely-distributed economically important plant-parasitic nematode group whose species-level identification relies largely on limited morphological characters including character-based tabular keys and molecular data of ribosomal and mitochondrial genes. In this study, a combined morphological and molecular analysis of three populations of R. goodeyi from Belgium, Poland and the Netherlands revealed important character variations of this species leading to synonymisation of R. rhomboides with R. goodeyi, and a high nucleotide variation within cox1 gene sequences in these populations. Additional Illumina sequencing of DNA from individuals of the Dutch population revealed two variants of mitogenomes each of approximately 23 Kb in size, differing by about 9% and containing eleven protein coding genes, two ribosomal RNA genes and up to 29 transfer RNA genes. In addition to the first representative whole genome shotgun sequence datasets of the genus Rotylenchus, this study also provides the full length mitogenome and the ribosomal DNA sequences of R. goodeyi.


2021 ◽  
Author(s):  
Tatiana Kulikova ◽  
Antonina Maslova ◽  
Polina Starshova ◽  
Juan Sebastian Rodriguez ◽  
Alla Krasikova

In diplotene oocyte nuclei of all vertebrate species, except mammals, chromosomes lack interchromosomal contacts and chromatin is linearly compartmentalized into distinct chromomere-loop complexes forming lampbrush chromosomes. However, the mechanisms underlying the formation of chromomere-loop complexes remain unexplored. Here we aimed to juxtapose somatic topologically associating domains (TADs), recently identified in chicken embryonic fibroblasts, with chromomere-loop complexes in lampbrush meiotic chromosomes. By measuring 3D-distances and colocalization between linear equidistantly located genomic loci, positioned within one TAD or separated by a TAD border, we confirmed the presence of predicted TADs in chicken embryonic fibroblast nuclei. Using three-colored FISH with BAC probes we mapped equidistant genomic regions included in several sequential somatic TADs on isolated chicken lampbrush chromosomes. Eight genomic regions, each comprising two or three somatic TADs, were mapped to non-overlapping neighboring lampbrush chromatin domains - lateral loops, chromomeres or chromomere-loop complexes. Genomic loci from the neighboring somatic TADs could localize in one lampbrush chromomere-loop complex, while genomic loci belonging to the same somatic TAD could be localized in neighboring lampbrush chromomere-loop domains. In addition, FISH-mapping of BAC probes to the nascent transcripts on the lateral loops indicates transcription of at least 17 protein-coding genes and 2 non-coding RNA genes during the lampbrush stage of chicken oogenesis, including genes involved in oocyte maturation and early embryo development.


2017 ◽  
Vol 292 (14) ◽  
pp. 5624-5633 ◽  
Author(s):  
Yangyang Liu ◽  
Xiao Han ◽  
Junting Yuan ◽  
Tuoyu Geng ◽  
Shihao Chen ◽  
...  

Author(s):  
Zhuomin Wu ◽  
Xiaoxia Liu ◽  
Li Liu ◽  
Houliang Deng ◽  
Jingjing Zhang ◽  
...  

AbstractLong non-coding RNAs (lncRNAs) are series of transcripts with important biological functions. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. In this review, we highlight the mechanisms of dynamic lncRNA expression. The chromatin state contributes to the low and specific expression of lncRNAs. The transcription of non-coding RNA genes is regulated by many core transcription factors applied to protein-coding genes. However, specific DNA sequences may allow their unsynchronized transcription with their location-associated mRNAs. Additionally, there are multiple mechanisms involved in the post-transcriptional regulation of lncRNAs. Among these, microRNAs might have indispensible regulatory effects on lncRNAs, based on recent discoveries.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vikas Kumar ◽  
Kaomud Tyagi ◽  
Rajasree Chakraborty ◽  
Priya Prasad ◽  
Shantanu Kundu ◽  
...  

AbstractThe complete mitochondrial genome of Lyrognathus crotalus is sequenced, annotated and compared with other spider mitogenomes. It is 13,865 bp long and featured by 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (rRNAs), 13 protein-coding genes (PCGs), and a control region (CR). Most of the PCGs used ATN start codon except cox3, and nad4 with TTG. Comparative studies indicated the use of TTG, TTA, TTT, GTG, CTG, CTA as start codons by few PCGs. Most of the tRNAs were truncated and do not fold into the typical cloverleaf structure. Further, the motif (CATATA) was detected in CR of nine species including L. crotalus. The gene arrangement of L. crotalus compared with ancestral arthropod showed the transposition of five tRNAs and one tandem duplication random loss (TDRL) event. Five plesiomophic gene blocks (A-E) were identified, of which, four (A, B, D, E) retained in all taxa except family Salticidae. However, block C was retained in Mygalomorphae and two families of Araneomorphae (Hypochilidae and Pholcidae). Out of 146 derived gene boundaries in all taxa, 15 synapomorphic gene boundaries were identified. TreeREx analysis also revealed the transposition of trnI, which makes three derived boundaries and congruent with the result of the gene boundary mapping. Maximum likelihood and Bayesian inference showed similar topologies and congruent with morphology, and previously reported multi-gene phylogeny. However, the Gene-Order based phylogeny showed sister relationship of L. crotalus with two Araneomorphae family members (Hypochilidae and Pholcidae) and other Mygalomorphae species.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Min Lu ◽  
Xinglei Qin ◽  
Yajun Zhou ◽  
Gang Li ◽  
Zhaoyang Liu ◽  
...  

AbstractGemcitabine is the first-line chemotherapy drug for cholangiocarcinoma (CCA), but acquired resistance has been frequently observed in CCA patients. To search for potential long noncoding RNAs (lncRNAs) involved in gemcitabine resistance, two gemcitabine resistant CCA cell lines were established and dysregulated lncRNAs were identified by lncRNA microarray. Long intergenic non-protein coding RNA 665 (LINC00665) were found to rank the top 10 upregulated lncRNAs in our study, and high LINC00665 expression was closely associated with poor prognosis and chemoresistance of CCA patients. Silencing LINC00665 in gemcitabine resistant CCA cells impaired gemcitabine tolerance, while enforced LINC00665 expression increased gemcitabine resistance of sensitive CCA cells. The gemcitabine resistant CCA cells showed increased EMT and stemness properties, and silencing LINC00665 suppressed sphere formation, migration, invasion and expression of EMT and stemness markers. In addition, Wnt/β-Catenin signaling was activated in gemcitabine resistant CCA cells, but LINC00665 knockdown suppressed Wnt/β-Catenin activation. B-cell CLL/lymphoma 9-like (BCL9L), the nucleus transcriptional regulators of Wnt/β-Catenin signaling, plays a key role in the nucleus translocation of β-Catenin and promotes β-Catenin-dependent transcription. In our study, we found that LINC00665 regulated BCL9L expression by acting as a molecular sponge for miR-424-5p. Moreover, silencing BCL9L or miR-424-5p overexpression suppressed gemcitabine resistance, EMT, stemness and Wnt/β-Catenin activation in resistant CCA cells. In conclusion, our results disclosed the important role of LINC00665 in gemcitabine resistance of CCA cells, and provided a new biomarker or therapeutic target for CCA treament.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Yiheng Wang ◽  
Sheng Wang ◽  
Yanlei Liu ◽  
Qingjun Yuan ◽  
Jiahui Sun ◽  
...  

Abstract Background Atractylodes DC is the basic original plant of the widely used herbal medicines “Baizhu” and “Cangzhu” and an endemic genus in East Asia. Species within the genus have minor morphological differences, and the universal DNA barcodes cannot clearly distinguish the systemic relationship or identify the species of the genus. In order to solve these question, we sequenced the chloroplast genomes of all species of Atractylodes using high-throughput sequencing. Results The results indicate that the chloroplast genome of Atractylodes has a typical quadripartite structure and ranges from 152,294 bp (A. carlinoides) to 153,261 bp (A. macrocephala) in size. The genome of all species contains 113 genes, including 79 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Four hotspots, rpl22-rps19-rpl2, psbM-trnD, trnR-trnT(GGU), and trnT(UGU)-trnL, and a total of 42–47 simple sequence repeats (SSR) were identified as the most promising potentially variable makers for species delimitation and population genetic studies. Phylogenetic analyses of the whole chloroplast genomes indicate that Atractylodes is a clade within the tribe Cynareae; Atractylodes species form a monophyly that clearly reflects the relationship within the genus. Conclusions Our study included investigations of the sequences and structural genomic variations, phylogenetics and mutation dynamics of Atractylodes chloroplast genomes and will facilitate future studies in population genetics, taxonomy and species identification.


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