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1.
Nat Commun ; 14(1): 549, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725857

RESUMO

The genetics underlying tuberculosis (TB) pathophysiology are poorly understood. Human genome-wide association studies have failed so far to reveal reproducible susceptibility loci, attributed in part to the influence of the underlying Mycobacterium tuberculosis (Mtb) bacterial genotype on the outcome of the infection. Several studies have found associations of human genetic polymorphisms with Mtb phylo-lineages, but studies analysing genome-genome interactions are needed. By implementing a phylogenetic tree-based Mtb-to-human analysis for 714 TB patients from Thailand, we identify eight putative genetic interaction points (P < 5 × 10-8) including human loci DAP and RIMS3, both linked to the IFNγ cytokine and host immune system, as well as FSTL5, previously associated with susceptibility to TB. Many of the corresponding Mtb markers are lineage specific. The genome-to-genome analysis reveals a complex interactome picture, supports host-pathogen adaptation and co-evolution in TB, and has potential applications to large-scale studies across many TB endemic populations matched for host-pathogen genomic diversity.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Estudo de Associação Genômica Ampla , Filogenia , Tuberculose/microbiologia , Mycobacterium tuberculosis/genética , Genoma , Interações Hospedeiro-Patógeno/genética
2.
Sci Rep ; 13(1): 1821, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726023

RESUMO

Egg production traits are economically important in laying ducks. Genetic molecular mechanisms and candidate genes underlying these traits remain unclear. In this study, whole genome variants were identified through whole-genome resequencing using three high-egg producing (HEN) and three low-egg producing (LEN) laying ducks. The gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genome (KEGG) pathways for the genes of common differential variants between HEN and LEN ducks were determined. Frizzled class receptor 6 (FZD6) was further genotyped using the Sequenom MassARRAY iPLEX platform. The association of FZD6 gene polymorphisms with 73 egg production and weight traits in 329 female ducks were estimated. A total of 65,535 single nucleotide polymorphisms (SNPs) and 4,702 indels were identified across the genome. Fourteen GO terms and 14 KEGG pathways were determined for the genes of common differential variants, including MAPK signaling, Wnt signaling, melanogenesis and calcium signaling pathways, which are key functional pathways for poultry egg production reported in previous reports. Further analysis showed that 27 SNPs of FZD6 were associated with three early egg production of duck and egg weight traits, including egg production at 17 weeks (EP17), 18 weeks (EP18) and 19 weeks (EP19) and egg weight at 59 weeks (EW59). The FZD6 should be considered a novel candidate gene for egg production traits in laying ducks.


Assuntos
Patos , Genoma , Animais , Feminino , Patos/genética , Genótipo , Fenótipo , Polimorfismo de Nucleotídeo Único
3.
RNA Biol ; 20(1): 48-58, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36727270

RESUMO

Automated genome annotation is essential for extracting biological information from sequence data. The identification and annotation of tRNA genes is frequently performed by the software package tRNAscan-SE, the output of which is listed for selected genomes in the Genomic tRNA database (GtRNAdb). Here, we highlight a pervasive error in prokaryotic tRNA gene sets on GtRNAdb: the mis-categorization of partial, non-canonical tRNA genes as standard, canonical tRNA genes. Firstly, we demonstrate the issue using the tRNA gene sets of 20 organisms from the archaeal taxon Thermococcaceae. According to GtRNAdb, these organisms collectively deviate from the expected set of tRNA genes in 15 instances, including the listing of eleven putative canonical tRNA genes. However, after detailed manual annotation, only one of these eleven remains; the others are either partial, non-canonical tRNA genes resulting from the integration of genetic elements or CRISPR-Cas activity (seven instances), or attributable to ambiguities in input sequences (three instances). Secondly, we show that similar examples of the mis-categorization of predicted tRNA sequences occur throughout the prokaryotic sections of GtRNAdb. While both canonical and non-canonical prokaryotic tRNA gene sequences identified by tRNAscan-SE are biologically interesting, the challenge of reliably distinguishing between them remains. We recommend employing a combination of (i) screening input sequences for the genetic elements typically associated with non-canonical tRNA genes, and ambiguities, (ii) activating the tRNAscan-SE automated pseudogene detection function, and (iii) scrutinizing predicted tRNA genes with low isotype scores. These measures greatly reduce manual annotation efforts, and lead to improved prokaryotic tRNA gene set predictions.


Assuntos
Genoma , RNA de Transferência , RNA de Transferência/genética
4.
Methods Mol Biol ; 2624: 19-42, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36723807

RESUMO

The genome 3D structure is central to understanding how disease-associated genetic variants in the noncoding genome regulate their target genes. Genome architecture spans large-scale structures determined by fine-grained regulatory elements, making it challenging to predict the effects of sequence and structural variants. Experimental approaches for chromatin interaction mapping remain costly and time-consuming, limiting their use for interrogating changes of chromatin architecture associated with genomic variation at scale. Computational models to predict chromatin interactions have either interpreted chromatin at coarse resolution or failed to capture the long-range dependencies of larger sequence contexts. To bridge this gap, we previously developed deepC, a deep neural network approach to predict chromatin interactions from DNA sequence at megabase scale. deepC employs dilated convolutional layers to achieve simultaneously a large sequence context while interpreting the DNA sequence at single base pair resolution. Using transfer learning of convolutional weights trained to predict a compendium of chromatin features across cell types allows deepC to predict cell type-specific chromatin interactions from DNA sequence alone. Here, we present a detailed workflow to predict chromatin interactions with deepC. We detail the necessary data pre-processing steps, guide through deepC model training, and demonstrate how to employ trained models to predict chromatin interactions and the effect of sequence variations on genome architecture.


Assuntos
Cromatina , Sequências Reguladoras de Ácido Nucleico , Cromatina/genética , Sequência de Bases , Redes Neurais de Computação , Genoma
5.
Methods Mol Biol ; 2624: 87-114, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36723811

RESUMO

Mapping DNA modifications at the base resolution is now possible at the genome level thanks to advances in sequencing technologies. Long-read sequencing data can be used to identify modified base patterns. However, the downstream analysis of Pacific Biosciences (PacBio) or Oxford Nanopore Technologies (ONT) data requires the integration of genomic annotation and comprehensive filtering to prevent the accumulation of artifact signals. We present in this chapter, a linear workflow to fully analyze modified base patterns using the DNA Modification Annotation (DNAModAnnot) package. This workflow includes a thorough filtering based on sequencing quality and false discovery rate estimation and provides tools for a global analysis of DNA modifications. Here, we provide an application example of this workflow with PacBio data and guide the user by explaining expected outputs via a fully integrated Rmarkdown script. This protocol is presented with tips showing how to adapt the provided code for annotating epigenomes of any organism according to the user needs.


Assuntos
DNA , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Nucleotídeos em Larga Escala/métodos , DNA/genética , Genômica , Análise de Sequência de DNA/métodos , Genoma
6.
J Adv Res ; 44: 1-11, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725182

RESUMO

INTRODUCTION: Host shift of parasites may have devastating effects on the novel hosts. One remarkable example is that of the ectoparasitic mite Varroa destructor, which has shifted its host from Eastern honey bees (Apis cerana) to Western honey bees (Apis mellifera) and posed a global threat to apiculture. OBJECTIVES: To identify the genetic factors underlying the reproduction of host-shifted V. destructor on the new host. METHODS: Genome sequencing was conducted to construct the phylogeny of the host-shifted and non-shifted mites and to screen for genomic signatures that differentiated them. Artificial infestation experiment was conducted to compare the reproductive difference between the mites, and transcriptome sequencing was conducted to find differentially expressed genes (DEGs) during the reproduction process. RESULTS: The host-shifted and non-shifted V. destructor mites constituted two genetically distinct lineages, with 15,362 high-FST SNPs identified between them. Oogenesis was upregulated in host-shifted mites on the new host A. mellifera relative to non-shifted mites. The transcriptomes of the host-shifted and non-shifted mites differed significantly as early as 1h post-infestation. The DEGs were associated with nine genes carrying nonsynonymous high-FST SNPs, including mGluR2-like, Lamb2-like and Vitellogenin 6-like, which were also differentially expressed, and eIF4G, CG5800, Dap160 and Sas10, which were located in the center of the networks regulating the DEGs based on protein-protein interaction analysis. CONCLUSIONS: The annotated functions of these genes were all associated with oogenesis. These genes appear to be the key genetic determinants of the oogenesis of host-shifted mites on the new host. Further study of these candidate genes will help elucidate the key mechanism underlying the success of host shifts of V. destructor.


Assuntos
Parasitos , Varroidae , Animais , Abelhas/genética , Varroidae/genética , Genoma , Parasitos/genética , Genômica , Oogênese/genética
7.
Adv Exp Med Biol ; 1398: 81-98, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36717488

RESUMO

Aquaporins (AQPs) are present not only in three domains of life, bacteria, eukaryotes, and archaea, but also in viruses. With the accumulating arrays of AQP superfamily, the evolutional relationship has attracted much attention with multiple publications on "the genome-wide identification and phylogenetic analysis" of AQP superfamily. A pair of NPA boxes forming a pore is highly conserved throughout the evolution and renders key residues for the classification of AQP superfamily into four groups: AQP1-like, AQP3-like, AQP8-like, and AQP11-like. The complexity of AQP family has mostly been achieved in nematodes and subsequent evolution has been directed toward increasing the number of AQPs through whole-genome duplications (WGDs) to extend the tissue specific expression and regulation. The discovery of the intracellular AQP (iAQP: AQP8-like and AQP11-like) and substrate transports by the plasma membrane AQP (pAQP: AQP1-like and AQP3-like) have accelerated the AQP research much more toward the transport of substrates with complex profiles. This evolutionary overview based on a simple classification of AQPs into four subfamilies will provide putative structural, functional, and localization information and insights into the role of AQP as well as clues to understand the complex diversity of AQP superfamily.


Assuntos
Aquaporinas , Genoma , Filogenia , Aquaporinas/genética , Aquaporinas/química , Aquaporinas/metabolismo
8.
Bioinformatics ; 39(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688709

RESUMO

SUMMARY: Gos is a declarative Python library designed to create interactive multiscale visualizations of genomics and epigenomics data. It provides a consistent and simple interface to the flexible Gosling visualization grammar. Gos hides technical complexities involved with configuring web-based genome browsers and integrates seamlessly within computational notebooks environments to enable new interactive analysis workflows. AVAILABILITY AND IMPLEMENTATION: Gos is released under the MIT License and available on the Python Package Index (PyPI). The source code is publicly available on GitHub (https://github.com/gosling-lang/gos), and documentation with examples can be found at https://gosling-lang.github.io/gos.


Assuntos
Biologia Computacional , Gansos , Animais , Genômica , Genoma , Biblioteca Gênica , Software
9.
Clin Epigenetics ; 15(1): 4, 2023 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611170

RESUMO

BACKGROUND: To explore the possible carcinogenesis and help better diagnose and treat patients with synchronous multiple primary lung cancers (sMPLC), we systematically investigated the genetic and DNA methylation profiles of early-stage sMPLC and single primary lung cancer (SPLC) and explored the immune profiles in the tumor microenvironment. METHODS: Hundred and ninety-one patients with 191 nodules in the SPLC group and 132 patients with 295 nodules in the sMPLC group were enrolled. All the samples were subjected to wide panel-genomic sequencing. Genome-wide DNA methylation was assessed using the Infinium Human Methylation 850 K BeadChip. RNA-seq and CIBERSORT analyses were performed to identify the immune characteristics in these two groups. RESULTS: Lesions from sMPLC patients had lower TMB levels than that from SPLC patients. sMPLC had a similar genetic mutational landscape with SPLC, despite some subgroup genetic discrepancies. Distinct DNA methylation patterns were identified between the two groups. The differentially methylated genes were related to immune response pathways. RNA-seq analyses revealed more immune-related DEGs in sMPLC. Accordingly, more immune-related biological processes and pathways were identified in sMPLC. Aberrant DNA methylation was associated with the abnormal expression of immune-related genes. CIBERSORT analysis revealed the infiltration of immune cells was different between the two groups. CONCLUSION: Our study for the first time demonstrated genetic, epigenetic, and immune profile discrepancies between sMPLC and SPLC. Relative to the similar genetic mutational landscape, the DNA methylation patterns and related immune profiles were significantly different between sMPLC and SPLC, indicating their essential roles in the initiation and development of sMPLC.


Assuntos
Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Metilação de DNA , Genoma , Mutação , Neoplasias Pulmonares/patologia , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Microambiente Tumoral
10.
Proc Natl Acad Sci U S A ; 120(6): e2217868120, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36719923

RESUMO

Single-cell RNA sequencing combined with genome-scale metabolic models (GEMs) has the potential to unravel the differences in metabolism across both cell types and cell states but requires new computational methods. Here, we present a method for generating cell-type-specific genome-scale models from clusters of single-cell RNA-Seq profiles. Specifically, we developed a method to estimate the minimum number of cells required to pool to obtain stable models, a bootstrapping strategy for estimating statistical inference, and a faster version of the task-driven integrative network inference for tissues algorithm for generating context-specific GEMs. In addition, we evaluated the effect of different RNA-Seq normalization methods on model topology and differences in models generated from single-cell and bulk RNA-Seq data. We applied our methods on data from mouse cortex neurons and cells from the tumor microenvironment of lung cancer and in both cases found that almost every cell subtype had a unique metabolic profile. In addition, our approach was able to detect cancer-associated metabolic differences between cancer cells and healthy cells, showcasing its utility. We also contextualized models from 202 single-cell clusters across 19 human organs using data from Human Protein Atlas and made these available in the web portal Metabolic Atlas, thereby providing a valuable resource to the scientific community. With the ever-increasing availability of single-cell RNA-Seq datasets and continuously improved GEMs, their combination holds promise to become an important approach in the study of human metabolism.


Assuntos
Perfilação da Expressão Gênica , Animais , Camundongos , Humanos , Perfilação da Expressão Gênica/métodos , Algoritmos , RNA-Seq , Genoma/genética , Análise de Célula Única/métodos , Análise de Sequência de RNA/métodos
11.
Proc Natl Acad Sci U S A ; 120(4): e2213887120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36669098

RESUMO

Massive DNA excision occurs regularly in ciliates, ubiquitous microbial eukaryotes with somatic and germline nuclei in the same cell. Tens of thousands of internally eliminated sequences (IESs) scattered throughout the ciliate germline genome are deleted during the development of the streamlined somatic genome. The genus Blepharisma represents one of the two high-level ciliate clades (subphylum Postciliodesmatophora) and, unusually, has dual pathways of somatic nuclear and genome development. This makes it ideal for investigating the functioning and evolution of these processes. Here we report the somatic genome assembly of Blepharisma stoltei strain ATCC 30299 (41 Mbp), arranged as numerous telomere-capped minichromosomal isoforms. This genome encodes eight PiggyBac transposase homologs no longer harbored by transposons. All appear subject to purifying selection, but just one, the putative IES excisase, has a complete catalytic triad. We hypothesize that PiggyBac homologs were ancestral excisases that enabled the evolution of extensive natural genome editing.


Assuntos
Cilióforos , Paramecium tetraurellia , Edição de Genes , Genoma , Cilióforos/genética , Paramecium tetraurellia/metabolismo , Núcleo Celular/metabolismo , DNA de Protozoário/genética
12.
Proc Natl Acad Sci U S A ; 120(4): e2209831120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36669112

RESUMO

We recently reported transposon mutagenesis as a significant driver of spontaneous mutations in the human fungal pathogen Cryptococcus deneoformans during murine infection. Mutations caused by transposable element (TE) insertion into reporter genes were dramatically elevated at high temperatures (37° vs. 30°) in vitro, suggesting that heat stress stimulates TE mobility in the Cryptococcus genome. To explore the genome-wide impact of TE mobilization, we generated transposon accumulation lines by in vitro passage of C. deneoformans strain XL280α for multiple generations at both 30° and at the host-relevant temperature of 37°. Utilizing whole-genome sequencing, we identified native TE copies and mapped multiple de novo TE insertions in these lines. Movements of the T1 DNA transposon occurred at both temperatures with a strong bias for insertion between gene-coding regions. By contrast, the Tcn12 retrotransposon integrated primarily within genes and movement occurred exclusively at 37°. In addition, we observed a dramatic amplification in copy number of the Cnl1 (Cryptococcus neoformans LINE-1) retrotransposon in subtelomeric regions under heat-stress conditions. Comparing TE mutations to other sequence variations detected in passaged lines, the increase in genomic changes at elevated temperatures was primarily due to mobilization of the retroelements Tcn12 and Cnl1. Finally, we found multiple TE movements (T1, Tcn12, and Cnl1) in the genomes of single C. deneoformans isolates recovered from infected mice, providing evidence that mobile elements are likely to facilitate microevolution and rapid adaptation during infection.


Assuntos
Criptococose , Cryptococcus neoformans , Humanos , Animais , Camundongos , Retroelementos/genética , Cryptococcus neoformans/genética , Criptococose/genética , Genoma , Resposta ao Choque Térmico/genética , Elementos de DNA Transponíveis/genética
13.
Sci Rep ; 13(1): 1115, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36670113

RESUMO

Sus scrofa is a globally distributed livestock species that still maintains two different ways of life: wild and domesticated. Herein, we detected copy number variation (CNV) of 328 animals using short read alignment on Sscrofa11.1. We compared CNV among five groups of porcine populations: Asian domesticated (AD), European domesticated (ED), Asian wild (AW), European wild (EW), and Near Eastern wild (NEW). In total, 21,673 genes were identified on 154,872 copy number variation region (CNVR). Differences in gene copy numbers between populations were measured by considering the variance-based value [Formula: see text] and the one-way ANOVA test followed by Scheffe test. As a result, 111 genes were suggested as copy number variable genes. Abnormally gained copy number on EEA1 in all populations was suggested the presence of minor CNV in the reference genome assembly, Sscrofa11.1. Copy number variable genes were related to meat quality, immune response, and reproduction traits. Hierarchical clustering of all individuals and mean pairwise [Formula: see text] in breed level were visualized genetic relationship of 328 individuals and 56 populations separately. Our findings have shown how the complex history of pig evolution appears in genome-wide CNV of various populations with different regions and lifestyles.


Assuntos
Variações do Número de Cópias de DNA , Genoma , Animais , Suínos/genética , Dosagem de Genes , Fenótipo , Sus scrofa/genética
14.
Genome Biol ; 24(1): 8, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650523

RESUMO

BACKGROUND: CRISPR-based toolkits have dramatically increased the ease of genome and epigenome editing. SpCas9 is the most widely used nuclease. However, the difficulty of delivering SpCas9 and inability to modulate its expression in vivo hinder its widespread adoption in large animals. RESULTS: Here, to circumvent these obstacles, a doxycycline-inducible SpCas9-expressing (DIC) pig model was generated by precise knock-in of the binary tetracycline-inducible expression elements into the Rosa26 and Hipp11 loci, respectively. With this pig model, in vivo and/or in vitro genome and epigenome editing could be easily realized. On the basis of the DIC system, a convenient Cas9-based conditional knockout strategy was devised through controlling the expression of rtTA component by tissue-specific promoter, which allows the one-step generation of germline-inherited pigs enabling in vivo spatiotemporal control of gene function under simple chemical induction. To validate the feasibility of in vivo gene mutation with DIC pigs, primary and metastatic pancreatic ductal adenocarcinoma was developed by delivering a single AAV6 vector containing TP53-sgRNA, LKB1-sgRNA, and mutant human KRAS gene into the adult pancreases. CONCLUSIONS: Together, these results suggest that DIC pig resources will provide a powerful tool for conditional in vivo genome and epigenome modification for fundamental and applied research.


Assuntos
Sistemas CRISPR-Cas , Doxiciclina , Humanos , Animais , Suínos , Doxiciclina/farmacologia , Mutação , Genoma , Edição de Genes/métodos
15.
Evolution ; 77(1): 36-48, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622280

RESUMO

Understanding the mechanisms that generate genetic variation, and thus contribute to the process of adaptation, is a major goal of evolutionary biology. Mutation and genetic exchange have been well studied as mechanisms to generate genetic variation. However, there are additional factors, such as genome architecture, that may also impact the amount of genetic variation in some populations, and the extent to which these variation generating mechanisms are themselves shaped by natural selection is still an open question. To test the effect of genome architecture on the generation of genetic variation, and hence evolvability, we studied Tetrahymena thermophila, a ciliate with an unusual genome structure and mechanism of nuclear division, called amitosis, whereby homologous chromosomes are randomly distributed to daughter cells. Amitosis leads to genetic variation among the asexual descendants of a newly produced sexual progeny because different progeny cells will contain different combinations of parental alleles. We hypothesize that amitosis thus increases the evolvability of newly produced sexual progeny relative to their unmated parents and species that undergo mitosis. To test this hypothesis, we used experimental evolution and simulations to compare the rate of adaptation in T. thermophila populations founded by a single sexual progeny to parental populations that had not had sex in many generations. The populations founded by a sexual progeny adapted more quickly than parental populations in both laboratory populations and simulated populations. This suggests that the additional genetic variation generated by amitosis of a heterozygote can increase the rate of adaptation following sex and may help explain the evolutionary success of the unusual genetic architecture of Tetrahymena and ciliates more generally.


Assuntos
Tetrahymena thermophila , Tetrahymena thermophila/genética , Cromossomos , Mutação , Genoma
16.
Evolution ; 77(1): 186-198, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622671

RESUMO

Epigenetic modifications are thought to be one of the molecular mechanisms involved in plastic adaptive responses to environmental variation. However, studies reporting associations between genome-wide epigenetic changes and habitat-specific variations in life history traits (e.g., lifespan, reproduction) are still scarce, likely due to the recent application of methylome resequencing methods to non-model species. In this study, we examined associations between whole genome DNA methylation and environmentally driven life history variation in 2 lineages of a marine fish, the capelin (Mallotus villosus), from North America and Europe. In both lineages, capelin harbor 2 contrasting life history tactics (demersal vs. beach-spawning). Performing whole genome and methylome sequencing, we showed that life history tactics are associated with epigenetic changes in both lineages, though the effect was stronger in European capelin. Genetic differentiation between the capelin harboring different life history tactics was negligible, but we found genome-wide methylation changes in both lineages. We identified 9,125 European and 199 North American differentially methylated regions (DMRs) due to life history. Gene ontology (GO) enrichment analysis for both lineages revealed an excess of terms related to neural function. Our results suggest that environmental variation causes important epigenetic changes that are associated with contrasting life history tactics in lineages with divergent genetic backgrounds, with variable importance of genetic variation in driving epigenetic variation. Our study emphasizes the potential role of genome-wide epigenetic variation in adaptation to environmental variation.


Assuntos
Traços de História de Vida , Osmeriformes , Animais , Metilação de DNA , DNA , Epigênese Genética , Genoma , Osmeriformes/fisiologia
17.
Bioinformatics ; 39(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648328

RESUMO

MOTIVATION: Protein-to-genome alignment is critical to annotating genes in non-model organisms. While there are a few tools for this purpose, all of them were developed over 10 years ago and did not incorporate the latest advances in alignment algorithms. They are inefficient and could not keep up with the rapid production of new genomes and quickly growing protein databases. RESULTS: Here, we describe miniprot, a new aligner for mapping protein sequences to a complete genome. Miniprot integrates recent techniques such as k-mer sketch and vectorized dynamic programming. It is tens of times faster than existing tools while achieving comparable accuracy on real data. AVAILABILITY AND IMPLEMENTATION: https://github.com/lh3/miniport.


Assuntos
Algoritmos , Software , Análise de Sequência de DNA/métodos , Alinhamento de Sequência , Genoma
18.
Methods Mol Biol ; 2606: 135-158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36592313

RESUMO

CRISPR base editors are genome-modifying proteins capable of creating single-base substitutions in DNA but without the requirement for a DNA double-strand break. Given their ability to precisely edit DNA, they hold tremendous therapeutic potential. Here, we describe procedures for delivering base editors in vivo via adeno-associated virus (AAV) vectors, a promising engineered gene delivery vehicle capable of transducing a range of cell types and tissues. We provide step by step protocols for (i) designing and validating base editing systems, (ii) packaging base editors into recombinant AAV vector particles, (iii) delivering AAV to the central nervous system via intrathecal injection, and (iv) quantifying base editing frequencies by next-generation sequencing.


Assuntos
Dependovirus , Vetores Genéticos , Dependovirus/genética , Vetores Genéticos/genética , Técnicas de Transferência de Genes , DNA , Genoma , Sistemas CRISPR-Cas
19.
BMC Ecol Evol ; 23(1): 2, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658479

RESUMO

BACKGROUND: Reconstructing phylogenetic relationships with genomic data remains a challenging endeavor. Numerous phylogenomic studies have reported incongruent gene trees when analyzing different genomic regions, complicating the search for a 'true' species tree. Some authors have argued that genomic regions of increased divergence (i.e. differentiation islands) reflect the species tree, although other studies have shown that these regions might produce misleading topologies due to species-specific selective sweeps or ancient introgression events. In this study, we tested the extent to which highly differentiated loci can resolve phylogenetic relationships in the Bean Goose complex, a group of goose taxa that includes the Taiga Bean Goose (Anser fabalis), the Tundra Bean Goose (Anser serrirostris) and the Pink-footed Goose (Anser brachyrhynchus). RESULTS: First, we show that a random selection of genomic loci-which mainly samples the undifferentiated regions of the genome-results in an unresolved species complex with a monophyletic A. brachyrhynchus embedded within a paraphyletic cluster of A. fabalis and A. serrirostris. Next, phylogenetic analyses of differentiation islands converged upon a topology of three monophyletic clades in which A. brachyrhynchus is sister to A. fabalis, and A. serrirostris is sister to the clade uniting these two species. Close inspection of the locus trees within the differentiated regions revealed that this topology was consistently supported over other phylogenetic arrangements. As it seems unlikely that selection or introgression events have impacted all differentiation islands in the same way, we are convinced that this topology reflects the 'true' species tree. Additional analyses, based on D-statistics, revealed extensive introgression between A. fabalis and A. serrirostris, which partly explains the failure to resolve the species complex with a random selection of genomic loci. Recent introgression between these taxa has probably erased the phylogenetic branching pattern across a large section of the genome, whereas differentiation islands were unaffected by the homogenizing gene flow and maintained the phylogenetic patterns that reflect the species tree. CONCLUSIONS: The evolution of the Bean Goose complex can be depicted as a simple bifurcating tree, but this would ignore the impact of introgressive hybridization. Hence, we advocate that the evolutionary relationships between these taxa are best represented as a phylogenetic network.


Assuntos
Gansos , Genoma , Animais , Filogenia , Gansos/genética , Genômica , Fluxo Gênico
20.
Genome Biol ; 24(1): 12, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658660

RESUMO

BACKGROUND: High-order chromatin structure plays important roles in gene regulation. However, the diversity of the three-dimensional (3D) genome across plant accessions are seldom reported. RESULTS: Here, we perform the pan-3D genome analysis using Hi-C sequencing data from 27 soybean accessions and comprehensively investigate the relationships between 3D genomic variations and structural variations (SVs) as well as gene expression. We find that intersection regions between A/B compartments largely contribute to compartment divergence. Topologically associating domain (TAD) boundaries in A compartments exhibit significantly higher density compared to those in B compartments. Pan-3D genome analysis shows that core TAD boundaries have the highest transcription start site (TSS) density and lowest GC content and repeat percentage. Further investigation shows that non-long terminal repeat (non-LTR) retrotransposons play important roles in maintaining TAD boundaries, while Gypsy elements and satellite repeats are associated with private TAD boundaries. Moreover, presence and absence variation (PAV) is found to be the major contributor to 3D genome variations. Nevertheless, approximately 55% of 3D genome variations are not associated with obvious genetic variations, and half of them affect the flanking gene expression. In addition, we find that the 3D genome may also undergo selection during soybean domestication. CONCLUSION: Our study sheds light on the role of 3D genomes in plant genetic diversity and provides a valuable resource for studying gene regulation and genome evolution.


Assuntos
Genoma , Soja , Soja/genética , Regulação da Expressão Gênica , Retroelementos , Genoma de Planta , Cromatina
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