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Characterization of FLOWERING LOCUS T-related genes and their putative gene regulatory network in semi-winter Brassica napus cultivar Zhongshaung11.

In many species, FLOWERING LOCUS T (FT)-like genes promote the floral transition by integrating environmental signals, in particular photoperiod, and internal cues. Here we show that Brassica napus contains six FT-like genes and two pseudogenes belonging to three orthogroups. All B. napus FT-like genes induce early flowering when expressed at the shoot apical meristems of Arabidopsis thaliana ft mutants; however, BnaFT.C6 and non-orthologous FT-like genes do not encode fully functional mobile florigens. In the case of BnFT.C6, the functional change is associated with a T to C amino acid change that is restricted to semi-winter accessions. Expression of orthologs of FT is photoperiod-dependent, and two distal enhancers are conserved; however, the homeologs BnaFT.A7 and BnaFT.C6 show rearrangements of DNA motifs binding NF-Y/CO and NF-Y transcriptional activator complexes between the promoter and downstream enhancers. Motif rearrangements correlate with differences in tissue-specific expression. Furthermore, homeologs with rearranged motifs could not be transactivated by B. napus CO in transient assays, although they show LD photoperiod-dependent expression. We propose that differential diurnal expression of NF-Y genes contributes to the photoperiod-dependent regulation of B. napus FT genes.

Brassica napus

Fishing for a reelGene: evaluating gene models with evolution and machine learning.

Assembled genomes and their associated annotations have transformed our study of gene function. However, each new annotated assembly generates new gene models. Inconsistencies between annotations likely arise from biological and technical causes, including pseudogene misclassification, transposon activity, and intron retention from sequencing of unspliced transcripts. To evaluate gene model predictions, we developed reelGene, a pipeline of machine learning models focused on (1) transcription boundaries, (2) mRNA integrity, and (3) protein structure. The first two models leverage sequence characteristics and evolutionary conservation across related taxa to learn the grammar of conserved transcription boundaries and mRNA sequences, while the third uses the conserved evolutionary grammar of protein sequences to predict whether a gene can produce a protein. Evaluating 1.8 million transcript models in Zea mays ssp. mays (maize), reelGene classified 28% as incorrectly annotated or non-functional. We find that reelGene classifies 92.2% of genes in the maize proteome and 99.2% of genes within the maize classical gene list as functional. reelGene also provides a way to further investigate genome biology- for instance, reelGene indicates that 10.3% of dispensable genes in B73 are functional, and within retained duplicate genes, reelGene identifies a 30% bias toward the retention of the M1 subgenome when one copy is functional and the other is non-functional. As an annotation-evaluating tool, reelGene is directly applicable to species of the Andropogoneae tribe, including other important crops like sorghum and miscanthus. As a community resource, reelGene has been integrated onto MaizeGDB both as a browser track and as an individual Shiny App, allowing researchers to evaluate gene model accuracy and further investigate genome biology.

Machine Learning

Transcriptomic and enzymological evidence for plastid peptidoglycan synthesis in the gymnosperm Picea abies.

It is understood that a cyanobacterium was the progenitor of plastids and that the biosynthesis of cell wall peptidoglycan was lost during chloroplast evolution. However, accumulated data, especially from the moss Physcomitrium patens, suggest that peptidoglycan remains essential for plastid division in some land plants. A fundamental set of peptidoglycan biosynthesis (Mur) genes has been identified in the genomes of these land plants, while many angiosperms no longer encode some core Mur genes, including a bifunctional penicillin-binding protein (PBP). Ten incomplete Mur genes were previously identified in the genome of the gymnosperm Picea abies but these could be pseudogenes or encode proteins that have been repurposed. For instance, mutant albino maize and Arabidopsis seedlings possess a defective UDP-N-acetylmuramoyl-l-alanyl-d-glutamate--2,6-diaminopimelate ligase (MurE), an intact MurE ligase being essential for peptidoglycan synthesis. In this study, we isolated a full set of cDNAs for peptidoglycan biosynthesis from P. abies. GFP fusion proteins with either P. abies (Pa)MurE or PaPBP were detected in chloroplasts. Cross-species complementation assays with PaMurE in Arabidopsis albino MurE mutants and Physcomitrium MurE chloroplast division mutants showed that the gymnosperm MurE completely rescued both mutant phenotypes. Enzymatic assay of recombinant PaMurE proteins revealed they catalyze the same reaction performed by their bacterial MurE homologs. Moreover, the expression of the PaPbp cDNA partially rescued the giant chloroplast phenotype in the moss Pbp knockout line. These results are consistent with the operation of a functional Mur gene set in the Norway spruce genome.

Peptidoglycan

Bordetella pertussis risA, but not risS, is required for maximal expression of Bvg-repressed genes.

Expression of virulence determinants by Bordetella pertussis, the primary etiological agent of whooping cough, is regulated by the BvgAS two-component regulatory system. The role of a second two-component regulatory system, encoded by risAS, in this process is not defined. Here, we show that mutation of B. pertussis risA does not affect Bvg-activated genes or proteins. However, mutation of risA resulted in greatly diminished expression of Bvg-repressed antigens and decreased transcription of Bvg-repressed genes. In contrast, mutation of risS had no effect on the expression of Bvg-regulated molecules. Mutation of risA also resulted in decreased bacterial invasion in a HeLa cell model. However, decreased invasion could not be attributed to the decreased expression of Bvg-repressed products, suggesting that mutation of risA may affect the expression of a variety of genes. Unlike the risAS operons in B. parapertussis and B. bronchiseptica, B. pertussis risS is a pseudogene that encodes a truncated RisS sensor. Deletion of the intact part of the B. pertussis risS gene does not affect the expression of risA-dependent, Bvg-repressed genes. These observations suggest that RisA activation occurs through cross-regulation by a heterologous system.

Bacterial Adhesion

Assembly and characterization of the first complete mitochondrial genome of Epimedium sagittatum (Sieb. et Zucc.) Maxim (Berberidaceae):an invaluable traditional Chinese medicine.

BACKGROUND: Epimedium sagittatum (Sieb. et Zucc.) Maxim is an invaluable traditional Chinese medicine plant known for its properties of tonifying kidney yang, strengthening bones and muscles, and dispelling rheumatism. The chloroplast (cp) genome of E. sagittatum have been sequenced, offering critical insights for breeding and phylogenetic research. However, the mitochondrial (mt) genome of E. sagittatum remains uncharacterized, limiting comprehensive insights into its genomic evolution. RESULTS: In this study, we assembled the first complete mt genome of E. sagittatum employing Illumina and Nanopore sequencing technology and subsequently investigated comparative analysis with its closely related species. The mt genome of E. sagittatum was assembled as a multi-branched structure with a length of 339,191 bp, within a GC content of 46.91%. Our annotation results have shown 39 protein-coding genes (PCGs), 22 tRNA genes, three rRNA genes and four pseudogenes in the E. sagittatum mt genome. The analysis of sequence repeats has detected 79 simple sequence repeats (SSRs), 10 tandem repeats and 255 dispersed repeats in the E. sagittatum mt genome. A total of 720 C to U RNA editing sites of the 34 PCGs was predicted in E. sagittatum. The codons exhibited a strong preference for A or U bases in the E. sagittatum mt genome. The analysis of nucleotide diversity (Pi) highlighted differences in genetic variability across the tested genes, with atp9 gene exhibiting the highest genetic variation. Selection pressure analysis showed that most genes were affected by negative selection during evolution, whereas ccmB, rps10, and rps12 underwent positive selection in different plants. Additionally, a Bayesian phylogenetic tree showed that E. sagittatum was closely related to E. wushanense and E. pubescens. In total of 14 homologous fragments totaling 8,954 bp were identified between the cp and mt genomes of E. sagittatum. CONCLUSIONS: This study presents the first assembled and annotated mt genome of E. sagittatum, which provides a valuable genetic resource for the Epimedium genus and lays the foundation for investigating the phylogenetic relationship and genetic variation of this invaluable medicinal plant.

Epimedium

Convergent evolution of intestinal lineages in the phylum Methanobacteriota.

BACKGROUND: Representatives of the phylum Methanobacteriota occur in various anoxic environments, but only members of the genera Methanosphaera and Methanobrevibacter exclusively colonize the digestive tract of animals. Recent phylogenomic analyses revealed that the genus Methanobrevibacter, which harbors the majority of the intestinal species, is severely underclassified and represents a family-level taxon, "Methanobrevibacteraceae", that evolved entirely in the digestive tract of animals. RESULTS: Comparative genome analysis of 158 species of Methanobacteriota, including uncultured representatives in the Genome Taxonomy Database (GTDB), demonstrated that the intestinal lineages are clearly separated from the remaining members of the phylum. They differ from the non-intestinal lineages in genome size, GC content, coding density, an increased number of pseudogenes and adhesin-like proteins, and show numerous adaptations to the copiotrophic gut environment. A decreased biosynthetic potential led to a dependence on other community members and limits the dispersal of intestinal species into other habitats, which is reflected in coevolutionary patterns with their major host groups among arthropods, ungulates, and primates. Certain lineages even engaged in symbiotic associations with intestinal protists, presumably benefiting from the H2 produced by the hydrogenosomes of their anaerobic hosts. CONCLUSIONS: Our results reveal that the transition of free-living Methanobacteriota to a host-associated lifestyle involves the same genomic changes that were previously recognized in gut bacteria and bacterial endosymbionts of protists, reflecting resemblances between the two prokaryotic domains that are caused by evolutionary convergence in similar environments.

Animals

Decoding the PTTG family's contribution to LUAD pathogenesis: a comprehensive study on expression, epigenetics, and therapeutic interventions.

BACKGROUND: Lung adenocarcinoma (LUAD) stands as a prevalent malignancy, yet its pathology remains incompletely comprehended. METHODS: In this comprehensive study, we explored the roles of the pituitary tumor-transforming gene (PTTG) family, including PTTG1, PTTG2, and the pseudogene PTTG3P in lung adenocarcinoma (LUAD). Employing a multi-faceted approach, we conducted in-depth analyses using clinical samples and expression datasets. RESULTS: Our findings revealed a significant up-regulation of PTTG family genes in LUAD cell lines and tissue samples compared to adjacent normal controls, suggesting their potential as diagnostic biomarkers. Through promoter methylation and mutational analyses, we uncovered regulatory mechanisms influencing PTTG gene expression. The exploration of the PTTG family's impact on LUAD patient survival demonstrated their association with adverse outcomes, emphasizing their potential prognostic relevance. Moreover, functional assays demonstrated that the knockdown of PTTG1 and PTTG2 genes resulted in the reduction of cell proliferation, colony formation, and cell migration abilities in A549 and H1975 LUAD cells. Furthermore, our investigation extended to therapeutic avenues, where we identified Calcitriol as a potential drug within the DrugBank database to down-regulate PTTG genes. Molecular docking analyses provided insights into the strong interaction between Calcitriol and PTTG1/PTTG2 proteins, laying the groundwork for further exploration of Calcitriol in LUAD treatment. CONCLUSION: In conclusion, this study contributes a comprehensive understanding of the PTTG family's involvement in LUAD, shedding light on their diagnostic, prognostic, and therapeutic implications.

Humans

The complete and annotated mitochondrial genome of Hemileia vastatrix Race I, causal agent of coffee leaf rust.

Hemileia vastatrix is the fungal pathogen responsible for coffee leaf rust (CLR), the most economically important disease of Coffea arabica worldwide. Recently, the nuclear genome of this fungus was completely deciphered. However, the mitochondrial genome of H. vastatrix has remained undercharacterized. Here, we present the complete, circularized mitochondrial genome of H. vastatrix Race I (isolate HvRI), assembled using a hybrid approach combining PacBio HiFi long reads and BGIseq short reads. The genome is 173,525 bp in length with a GC content of 33.1% and encodes 41 functional genes, including 15 protein-coding genes, 2 rRNAs, and 24 tRNAs. The assembly reveals significant structural complexity, driven by intron expansion in the cox1 and cob genes. Notably, the atp8 gene contains a group II intron, rare for this locus, whose internal open reading frame displays evidence of pseudogenization via internal stop codons.. We also characterized a putative replication initiation zone (~1.2 kb) defined by a poly-G homopolymer and conserved regulatory motifs. The mitogenome of the HvRI isolate does not contain cob mutations that lead to amino acid substitutions G143A and F129L associated with the quinone outside inhibitor (QoI) fungicide resistance. This high-quality mitogenome is an important resource for comparative mitogenomics, population diversity studies, and the molecular surveillance of QoI fungicide resistance.

Genome, Mitochondrial

Comparative genomics of natural killer cell receptor gene clusters.

Many receptors on natural killer (NK) cells recognize major histocompatibility complex class I molecules in order to monitor unhealthy tissues, such as cells infected with viruses, and some tumors. Genes encoding families of NK receptors and related sequences are organized into two main clusters in humans: the natural killer complex on Chromosome 12p13.1, which encodes C-type lectin molecules, and the leukocyte receptor complex on Chromosome 19q13.4, which encodes immunoglobulin superfamily molecules. The composition of these gene clusters differs markedly between closely related species, providing evidence for rapid, lineage-specific expansions or contractions of sets of loci. The choice of NK receptor genes is polarized in the two species most studied, mouse and human. In mouse, the C-type lectin-related Ly49 gene family predominates. Conversely, the single Ly49 sequence is a pseudogene in humans, and the immunoglobulin superfamily KIR gene family is extensive. These different gene sets encode proteins that are comparable in function and genetic diversity, even though they have undergone species-specific expansions. Understanding the biological significance of this curious situation may be aided by studying which NK receptor genes are used in other vertebrates, especially in relation to species-specific differences in genes for major histocompatibility complex class I molecules.

Journal Article

A genomic and phenotypic investigation of pigeon-adaptive Salmonella.

Salmonella, a significant threat to public safety, inflicts substantial economic losses on the poultry industry. The unique "parental feeding" breeding model of pigeon farms, against the "all-in & all-out" biosecurity strategy, makes them susceptible to Salmonella infections and subsequent outbreaks of pigeon paratyphoid. This study initially studied three pigeon paratyphoid outbreak incidents in Henan, China, in which 53 strains of pigeon-origin Salmonella Typhimurium (STM) were identified. Whole-genome sequencing (WGS) and antimicrobial-resistant profile analysis revealed that the three outbreaks were caused by distinct STM clones (ST128-DT2, ST19-DT99). Global phylogenetic analysis suggested that the United States is a possible origin, indicating a risk of intercontinental transmission via pigeon eggs. Further bacterial virulence and invasion assays, including in vitro and in vivo assays, revealed that pigeon-host-adaptive STM, compared to broad-host-range STM, carried fewer resistance genes, exhibited higher invasion indices and pseudogene levels, displayed a non-rdar (red dry and rough) phenotype, and had strong biofilm formation capability. Additionally, they showed reduced virulence and invasiveness in mice but a pigeon-adaptive feature in cogent models. The collective results support the host adaptation for pigeons among DT2 and DT99 phage-type isolates.

Animals

Evolutionary adaptation of CCD4 enzymes in Buddleja alternifolia for crocetin biosynthesis.

INTRODUCTION: Carotenoid cleavage dioxygenase 4 (CCD4) enzymes play central roles in carotenoid turnover and apocarotenoid biosynthesis in plants. Despite their importance, the evolutionary mechanisms underlying diversification of CCD4 catalytic functions remain poorly understood. This study investigated the CCD gene family in Buddleja alternifolia, with particular emphasis on the expansion and functional evolution of the CCD4 subfamily. METHODS: A genome-wide identification and comparative analysis of CCD genes were performed in B. alternifolia. Genomic organization, phylogenetic relationships, and syntenic patterns were analyzed to investigate gene family expansion. Functional characterization of 11 BaCCD4 paralogs was conducted through biochemical assays, while structural analyses were used to identify sequence features associated with differences in substrate cleavage specificity. Gene expression profiling was performed to assess patterns of tissue-specific regulation. RESULTS: Twenty-three CCD genes were identified, including 12 CCD4 paralogs, representing one of the largest CCD4 expansions reported within Lamiales. Syntenic and genomic analyses revealed that recent tandem duplication events, particularly within a CCD4-rich region on chromosome 10, were the primary drivers of this expansion. The presence of pseudogenes in the same region supported an ongoing birth-and-death evolutionary process. Functional analyses demonstrated extensive biochemical diversification among BaCCD4 enzymes despite their high sequence similarity. Several paralogs catalyzed asymmetric carotenoid cleavage leading to citraurin production, whereas two paralogs, KAG8367281 and KAG8375220, exhibited symmetric zeaxanthin cleavage activity, producing crocetin dialdehyde, the direct precursor of crocins. Notably, these crocetin-producing enzymes belonged to closely related paralogous pairs whose counterparts displayed distinct cleavage specificities, indicating rapid neofunctionalization after duplication. Structural analyses suggested that subtle sequence variations, including indels affecting loop regions adjacent to the substrate access channel, may underlie changes in regioselectivity. Expression profiling further revealed tissue-specific expression patterns consistent with functional divergence among paralogs. DISCUSSION: These findings indicate that crocetin-forming activity in B. alternifolia likely evolved through progressive modifications of ancestral CCD4 functions rather than through a single evolutionary event. The remarkable expansion and diversification of the CCD4 subfamily provide evidence for the role of gene duplication and neofunctionalization in shaping carotenoid cleavage specificity. Collectively, this work establishes B. alternifolia as a valuable model for investigating the molecular evolution of CCD4 enzymes and the emergence of specialized apocarotenoid metabolism in plants.

CCD4 evolution

One-time duplication and ongoing loss of mitochondrial tRNA genes in Cryptocercus cockroaches.

Mitochondrial genome is a popular marker in phylogenetics and species diversity estimations. Mitogenome is relatively compact and conserved, while gene rearrangements were found in some species across various organisms. Models to explain the origin and evolution of gene rearrangement have been proposed but seldom demonstrated; empirical evidence from closely related species is particularly scarce. Here, through an intensive case study of the cockroach genus Cryptocercus Scudder, 1862, we elucidate the evolution of mitochondrial gene order. This study utilized 51 new samples and re-assembled raw reads of 26 published samples. A diversity of rearrangement patterns is recovered, especially in the tRNA gene cluster between ND3 and ND5, which is effectively explained by the duplication - random loss model. Specifically, the entire tRNA gene cluster was duplicated; this duplication is potentially facilitated by chance binding between the 3' end of ND5 gene and the ND3-trnA region during DNA replication. Furthermore, we reveal that one of the gene copies degenerated stochastically across lineages, directly contributing to the observed diversity in gene arrangement. Gene rearrangement patterns are apomorphies for certain clades, providing additional evidence for the inferred phylogeny and serving as potential indicators of species. This study underscores the importance of intensive sampling and rigorous data curation for deciphering the evolutionary mechanisms.

Duplication–random loss model

Prime Editing for p47phox-Deficient Chronic Granulomatous Disease.

Chronic granulomatous disease (CGD) is a severe monogenic immunodeficiency caused by damaging variants in genes required for microbicidal NADPH oxidase activity. Autosomal recessive p47phox-deficient CGD (p47-CGD) is predominantly caused by a two-nucleotide deletion in exon 2 (delGT) of NCF1. We developed PM359, an autologous CD34+ hematopoietic stem-cell therapy in which prime editing is used to correct delGT. Two participants received PM359 after myeloid conditioning with busulfan: neutrophils and platelets engrafted promptly in both patients. Adverse events were consistent with myeloid conditioning with busulfan. NADPH oxidase activity was observed in neutrophils within 1 month and was maintained for 6 months and 4 months as of the last follow-up visit in Participants 1 and 2, respectively. These results support further investigation of prime editing of CD34+ cells to treat p47-CGD. (Funded by Prime Medicine; ClinicalTrials.gov number, NCT06559176.).

Adolescent