The depletion of fossil fuel resources and the COsub.2 emissions coupled with petroleum-based industrial processes present a relevant issue for the whole of society. An alternative to the ...fossil-based production of chemicals is microbial fermentation using acetogens. Acetogenic bacteria are able to metabolize CO or COsub.2 (+Hsub.2) via the Wood–Ljungdahl pathway. As isopropanol is widely used in a variety of industrial branches, it is advantageous to find a fossil-independent production process. In this study, Acetobacterium woodii was employed to produce isopropanol via plasmid-based expression of the enzymes thiolase A, CoA-transferase, acetoacetate decarboxylase and secondary alcohol dehydrogenase. An examination of the enzymes originating from different organisms led to a maximum isopropanol production of 5.64 ± 1.08 mM using COsub.2 + Hsub.2 as the carbon and energy source. To this end, the genes thlA (encoding thiolase A) and ctfA/ctfB (encoding CoA-transferase) of Clostridium scatologenes, adc (encoding acetoacetate decarboxylase) originating from C. acetobutylicum and sadH (encoding secondary alcohol dehydrogenase) of C. beijerinckii DSM 6423 were employed. Since bottlenecks in the isopropanol production pathway are known, optimization of the strain was investigated, resulting in a 2.5-fold increase in isopropanol concentration.
Protein content is one of the main factors determining the end-use quality of wheat. NO APICAL MERISTEM-B1 (NAM-B1) is a major gene regulating wheat grain protein content. The present study aimed to ...identify new genetic resources using the wild-type NAM-B1 allele to breed high-protein-content wheat cultivars. We genotyped the HIGH GRAIN PROTEIN CONTENT-B1 (GPC-B1) locus and NAM-B1 allele in 165 wheat cultivars. A kompetitive allele-specific polymerase chain reaction (KASP) marker was designed for functional NAM-B1 allele screening. The results revealed that 41 out of 165 cultivars carried the GPC-B1 locus. Among the 41 GPC-B1-carrying cultivars, the wild-type NAM-B1 allele was identified in only 3 cultivars, none of which were Korean. The remaining 38 cultivars showed a 1-bp insertion in NAM-B1, resulting in a stop codon in the middle of the gene, rendering it nonfunctional. Overall, this study reveals that the utilization of the three selected cultivars possessing the wild-type NAM-B1 gene, in conjunction with the developed KASP assay, could increase the protein content in Korean wheat cultivars.
Cancer treatment has been always considered one of the most critical and vital themes of clinical issues. Many approaches have been developed, depending on the type and the stage of tumor. Gene ...therapy has the potential to revolutionize different cancer therapy. With the advent of recent bioinformatics technologies and genetic science, it become possible to identify, diagnose and determine the potential treatment using the technology of gene delivery. Several approaches have been developed and experimented in vitro and vivo for cancer therapy including: naked nucleic acids based therapy, targeting micro RNAs, oncolytic virotherapy, suicide gene based therapy, targeting telomerase, cell mediated gene therapy, and CRISPR/Cas9 based therapy. In this review, we present a straightforward introduction to cancer biology and occurrence, highlighting different viral and non-viral gene delivery systems for gene therapy and critically discussed the current and various strategies for cancer gene therapy.
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Decoding gene regulation in the fly brain Janssens, Jasper; Aibar, Sara; Taskiran, Ibrahim Ihsan ...
Nature (London),
01/2022, Letnik:
601, Številka:
7894
Journal Article
Recenzirano
Odprti dostop
The Drosophila brain is a frequently used model in neuroscience. Single-cell transcriptome analysis
, three-dimensional morphological classification
and electron microscopy mapping of the connectome
...have revealed an immense diversity of neuronal and glial cell types that underlie an array of functional and behavioural traits in the fly. The identities of these cell types are controlled by gene regulatory networks (GRNs), involving combinations of transcription factors that bind to genomic enhancers to regulate their target genes. Here, to characterize GRNs at the cell-type level in the fly brain, we profiled the chromatin accessibility of 240,919 single cells spanning 9 developmental timepoints and integrated these data with single-cell transcriptomes. We identify more than 95,000 regulatory regions that are used in different neuronal cell types, of which 70,000 are linked to developmental trajectories involving neurogenesis, reprogramming and maturation. For 40 cell types, uniquely accessible regions were associated with their expressed transcription factors and downstream target genes through a combination of motif discovery, network inference and deep learning, creating enhancer GRNs. The enhancer architectures revealed by DeepFlyBrain lead to a better understanding of neuronal regulatory diversity and can be used to design genetic driver lines for cell types at specific timepoints, facilitating their characterization and manipulation.
Abstract
Gene co-expression networks can be used to associate genes of unknown function with biological processes, to prioritize candidate disease genes or to discern transcriptional regulatory ...programmes. With recent advances in transcriptomics and next-generation sequencing, co-expression networks constructed from RNA sequencing data also enable the inference of functions and disease associations for non-coding genes and splice variants. Although gene co-expression networks typically do not provide information about causality, emerging methods for differential co-expression analysis are enabling the identification of regulatory genes underlying various phenotypes. Here, we introduce and guide researchers through a (differential) co-expression analysis. We provide an overview of methods and tools used to create and analyse co-expression networks constructed from gene expression data, and we explain how these can be used to identify genes with a regulatory role in disease. Furthermore, we discuss the integration of other data types with co-expression networks and offer future perspectives of co-expression analysis.
Chloroplast genomes have been widely used in studying plant phylogeny and evolution. Several chloroplast genome visualization tools have been developed to display the distribution of genes on the ...genome. However, these tools do not draw features, such as exons, introns, repetitive elements, and variable sites, disallowing in‐depth examination of the genome structures. Here, we developed and validated a software package called Chloroplast Genome Viewers (CPGView). CPGView can draw three maps showing (i) the distributions of genes, variable sites, and repetitive sequences, including microsatellites, tandem and dispersed repeats; (ii) the structure of the cis‐splicing genes after adjusting the exon‐intron boundary positions using a coordinate scaling algorithm, and (iii) the structure of the trans‐splicing gene rps12. To test the accuracy of CPGView, we sequenced, assembled, and annotated 31 chloroplast genomes from 31 genera of 22 families. CPGView drew maps correctly for all the 31 chloroplast genomes. Lastly, we used CPGView to examine 5998 publicly released chloroplast genomes from 2513 genera of 553 families. CPGView succeeded in plotting maps for 5882 but failed to plot maps for 116 chloroplast genomes. Further examination showed that the annotations of these 116 genomes had various errors needing manual correction. The test on newly generated data and publicly available data demonstrated the ability of CPGView to identify errors in the annotations of chloroplast genomes. CPGView will become a widely used tool to study the detailed structure of chloroplast genomes. The web version of CPGView can be accessed from http://www.1kmpg.cn/cpgview.
Summary
Arabidopsis thaliana is a long established model species for plant molecular biology, genetics and genomics, and studies of A. thaliana gene function provide the basis for formulating ...hypotheses and designing experiments involving other plants, including economically important species. A comprehensive understanding of the A. thaliana genome and a detailed and accurate understanding of the expression of its associated genes is therefore of great importance for both fundamental research and practical applications. Such goal is reliant on the development of new genetic and genomic resources, involving new methods of data acquisition and analysis. We present here the genome‐wide analysis of A. thaliana gene expression profiles across different organs and developmental stages using high‐throughput transcriptome sequencing. The expression of 25 706 protein‐coding genes, as well as their stability and their spatiotemporal specificity, was assessed in 79 organs and developmental stages. A search for alternative splicing events identified 37 873 previously unreported splice junctions, approximately 30% of them occurred in intergenic regions. These potentially represent novel spliced genes that are not included in the TAIR10 database. These data are housed in an open‐access web‐based database, TraVA (Transcriptome Variation Analysis, http://travadb.org/), which allows visualization and analysis of gene expression profiles and differential gene expression between organs and developmental stages.
Significance Statement
The development and update of genetic and genomic resources, involving new methods of data acquisition and analysis, is necessary even for such long established model organisms such as Arabidopsis thaliana. We present a transcriptome map of A. thaliana created using high‐throughput RNA sequencing. It covers 79 organs and developmental stages; the analysis allowed the determination of global characteristics of the A. thaliana transcriptome and to add splice junctions and predicted genes to our current knowledge of the A. thaliana genome.
Chalcone synthase (CHS) is the key enzyme in the first committed step of the flavonoid biosynthetic pathway and catalyzes the stepwise condensation of 4-coumaroyl-CoA and malonyl- CoA to naringenin ...chalcone. In plants, CHS is often encoded by a small family of genes that are temporally and spatially regulated. Our earlier studies have shown that GCHS4 is highly activated by ectopic expression of an MYB-type regulator GMYB10 in gerbera (Gerbera hybrida).
The tissue- and development-specific expression patterns of three gerbera CHS genes were examined. Virus-induced gene silencing (VIGS) was used to knock down GCHS1 and GCHS4 separately in gerbera inflorescences.
Our data show that GCHS4 is the only CHS encoding gene that is expressed in the cyanidin-pigmented vegetative tissues of gerbera cv Terraregina. GCHS3 expression is pronounced in the pappus bristles of the flowers. Expression of both GCHS1 and GCHS4 is high in the epidermal cells of gerbera petals, but only GCHS1 is contributing to flavonoid biosynthesis.
Gerbera contains a family of three CHS encoding genes showing different spatial and temporal regulation. GCHS4 expression in gerbera petals is regulated post-transcriptionally, at the level of either translation elongation or protein stability.
Trait-associated genetic variants affect complex phenotypes primarily via regulatory mechanisms on the transcriptome. To investigate the genetics of gene expression, we performed cis- and ...trans-expression quantitative trait locus (eQTL) analyses using blood-derived expression from 31,684 individuals through the eQTLGen Consortium. We detected cis-eQTL for 88% of genes, and these were replicable in numerous tissues. Distal trans-eQTL (detected for 37% of 10,317 trait-associated variants tested) showed lower replication rates, partially due to low replication power and confounding by cell type composition. However, replication analyses in single-cell RNA-seq data prioritized intracellular trans-eQTL. Trans-eQTL exerted their effects via several mechanisms, primarily through regulation by transcription factors. Expression of 13% of the genes correlated with polygenic scores for 1,263 phenotypes, pinpointing potential drivers for those traits. In summary, this work represents a large eQTL resource, and its results serve as a starting point for in-depth interpretation of complex phenotypes.
Chromatin is folded into successive layers to organize linear DNA. Genes within the same topologically associating domains (TADs) demonstrate similar expression and histone-modification profiles, and ...boundaries separating different domains have important roles in reinforcing the stability of these features. Indeed, domain disruptions in human cancers can lead to misregulation of gene expression. However, the frequency of domain disruptions in human cancers remains unclear. Here, as part of the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA), which aggregated whole-genome sequencing data from 2,658 cancers across 38 tumor types, we analyzed 288,457 somatic structural variations (SVs) to understand the distributions and effects of SVs across TADs. Notably, SVs can lead to the fusion of discrete TADs, and complex rearrangements markedly change chromatin folding maps in the cancer genomes. Notably, only 14% of the boundary deletions resulted in a change in expression in nearby genes of more than twofold.
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