Search Results (3,192)

The genomes of viruses in the Allexivirus genus encode the p42 protein, which is considered the hallmark of the genus. The functions of p42 have not yet been studied experimentally and cannot be predicted based on sequence similarity, as p42-related proteins are not found among known cell or viral proteins. Here, p42 of Shallot virus X (ShVX), the type allexivirus, is demonstrated to be translated via a leaky scanning mechanism on a template comprising three “triple gene block” (TGB) transport genes and the p42 gene. Sequence analysis shows that this p42 expression mechanism is conserved in the vast majority of allexiviruses. p42 binds single-stranded RNA (ssRNA) but not double-stranded RNA (dsRNA) in vitro and localizes to the cytoplasm in association with microtubules and microtubule-bound bodies. In transient expression assays, p42 exhibits weak but detectable suppression of silencing induced by ssRNA but not by dsRNA. In addition, p42 suppresses silencing in the context of virus infection. Furthermore, p42 inhibits nonsense-mediated RNA decay (NMD) induced by a long 3′-terminal untranslated region of mRNA. Taken together, these findings provide initial evidence that the ShVX TGB/p42 gene module functions as a single genomic unit in terms of protein expression, that p42 acts as a suppressor of NMD and silencing, and that it may have multiple roles, while the precise biological significance of p42 in these roles remains to be experimentally confirmed. Full article

Background: Transcription factors have been linked to changes in various physiological processes, such as attractive and rewarding phenotypes during plant–pollinator interactions. In the genus Petunia, most species are pollinated by bees, but hawkmoth- and bird pollination are also observed. Here, we aimed to test the hypothesis that species with the same pollination syndrome evolved through convergence, while differences in pollinators indicate divergence. We selected six genes (MYB-FL, DFR, EOBII, ODO1, BPBT, and NEC1) involved in establishing pollination syndromes to explore the potential role of cis-regulatory elements in shifts among pollination syndromes, attracting and rewarding pollinators. Methods: We retrieved the genomic sequences of genes from the genomes of four Petunia species, which exhibit distinct pollination syndromes. We analyzed the cis-regulatory elements, focusing on the structure and composition of motifs, and inferred the functions of these transcription factors using Gene Ontology analysis. Results: All sequences were highly conserved among species, with variations in promoter motif structure and TF binding sites. The evolutionary relationships among the genes closely reflected the species’ phylogeny. Likewise, regulatory elements and gene structure mostly followed the species’ evolutionary history. However, different pollination syndromes are present, and there is an unexpected lack of convergence between the two bee-pollinated species. Conclusions: Our findings showed that the most recent common ancestor of these species better predicts relationships among gene regulatory elements than does the pollination syndrome. To fully understand the evolution of pollination syndromes in Petunia, additional studies are needed to analyze entire pathways and compare genomes and transcriptomes. Full article

Squamosa Promoter-Binding Protein Like (SPL) is a critical transcription factor that plays a significant role in regulating plant growth and development. Mining the coconut SPL family offers valuable insights into the regulation of important agronomic traits, including the length of the juvenile phase. In this study, 25 CnSPLs were identified and were classified into eight subfamilies. Analysis of gene structure and conserved protein motifs indicated a high conservation of CnSPLs within the same subfamilies; however, variations in protein structure and gene length were observed across different subfamilies. Gene expansion analysis indicated that most gene members within subfamilies originated from duplications of the same genomic segment, and transposable element insertion contributed to the divergence of gene sequences within these subfamilies. Characterization of the miR156 target sequence in SPL transcripts revealed that subfamilies IV to VIII contained these sequences, while subfamilies I to III did not. In both coconut and 14 other plant species, some SPLs lost their miR156-binding loci due to gene structure variations. The gene expression profiles revealed significant divergence between miR156-targeted and non-targeted CnSPLs; the former exhibited low expression levels in the endosperm, while the latter showed comparable expression across all tissues. Notably, CnSPL15A demonstrated steadily increasing expression levels in leaves throughout successive leaf primordia and significantly promoted flowering when overexpressed in Arabidopsis. Transient expression assays and 5′ RACE confirmed that CnSPLs are targeted by miR156. This study establishes a foundation for investigating the evolutionary characteristics of CnSPLs and provides a theoretical framework for analyzing the functions of key CnSPLs involved in the coconut flowering control pathway. Full article

Lycium barbarum is a traditional medicinal and edible plant species in China, exhibiting notable salt tolerance that enables cultivation in salt-affected soils. However, intensifying soil salinization has rendered severe salt stress a critical limiting factor for its fruit yield and quality. Universal stress proteins (USPs) serve as crucial regulators for plant abiotic stress responses through developmental process modulation. Nevertheless, the characteristics and functional divergence of USP gene family members remain unexplored in L. barbarum. Here, we performed genome-wide identification and characterization of the USP gene family in L. barbarum, revealing 52 members unevenly distributed across all 12 chromosomes. Phylogenetic analysis classified these LbUSP members into four distinct groups, demonstrating the integration of the conserved USP domain and diverse motifs within each group. Collinearity analysis indicated a stronger synteny of LbUSPs with orthologs in Solanum lycopersicum than with other species (Arabidopsis thaliana, Vitis vinifera, and Oryza sativa), demonstrating that gene duplication coupled with functional conservation represented the primary mechanism underlying USP family expansion in L. barbarum. In silico promoter screening detected abundant cis-acting elements associated with abiotic/biotic stress responses (MYB and MYC binding sites), phytohormone regulation (ABRE motif), and growth/development processes (Box-4 and G-box). Transcriptome sequencing and RT-qPCR validation revealed tissue-specific differential expression patterns of LbUSP8, LbUSP11, LbUSP12, LbUSP23, and LbUSP25 in roots and stems under salt stress, identifying them as prime candidates for mediating salt resistance in L. barbarum. Our findings establish a foundation for the functional characterization of LbUSPs and molecular breeding of salt-tolerant L. barbarum cultivars. Full article

The ATP-binding cassette (ABC) gene family represents one of the most extensive and evolutionarily conserved groups of proteins, characterized by ATP-dependent transporters that mediate the movement of substrates across cellular membranes. Despite their well-documented functions in various biological processes, the specific contributions of ABC transporters in eggplant (Solanum melongena L.) remain unexplored. To address this gap, we conducted a comprehensive genome-wide identification and expression profiling of ABC transporter-encoding genes in eggplant. Our investigation identified 159 SmABC genes encoding ABC transporter that were irregularly dispersed across all 12 chromosomes. The encoded proteins exhibited considerable diversity in size, with amino acid lengths varying from 55 to 2628 residues, molecular weights ranging between 4.04 and 286.42 kDa, and isoelectric points spanning from 4.89 to 11.62. Phylogenetic analysis classified the SmABC transporters into eight distinct subfamilies, with the ABCG subfamily being the most predominant. Subcellular localization predictions revealed that most SmABC proteins were localized to the plasma membrane. Members within the same subfamily exhibited conserved motif arrangements and exon–intron structures, suggesting functional and evolutionary conservation. Promoter analysis identified both shared and unique cis-regulatory elements associated with transcriptional regulation. We identified 9 tandem duplication gene pairs and 20 segmental duplication pairs in the SmABC gene family, with segmental duplication being the major mode of expansion. Non-synonymous to synonymous substitutions (Ka/Ks) analysis revealed that paralogs of SmABC family genes underwent mainly purifying selection during the evolutionary process. Comparative genomic analysis demonstrated collinearity between eggplant, Arabidopsis thaliana, and tomato (Solanum lycopersicum), confirming homology among SmABC, AtABC, and SlABC genes. Tissue-specific expression profiling revealed differential SmABC expression patterns, with three distinct genes, SmABCA16, SmABCA17 and SmABCG15, showing preferential expression in purple-peeled fruits (A1, A3, and A5 accessions), implicating their potential involvement in anthocyanin transport. Functional validation via SmABCA16 silencing led to a significant downregulation of SmABCA16 and reduced purple coloration, indicating its regulatory role in anthocyanin transport in eggplant fruit peel. This comprehensive genomic and functional characterization of ABC transporters in eggplant establishes a critical foundation for understanding their biological roles and supports targeted breeding strategies to enhance fruit quality traits. Full article

Retroviruses are single-stranded RNA viruses that package two copies of their positively stranded RNA genomes as a non-covalent dimer into newly formed virions. This process is evolutionarily conserved, and disruption of genome dimerization results in production of non-infectious virus particles. Genome dimers can be packaged as homodimers, containing two identical RNAs, or heterodimers, consisting of two genetically distinct copies. Genome dimerization generates genetic diversity, and different retroviruses have preferences for the type of genome dimers packaged into virions. We developed a novel imaging approach to specifically label and detect retroviral genome heterodimers in cells using a modified bimolecular fluorescence complementation (BiFC) technique. This method utilizes viral genomes encoding two different RNA stem-loop cassettes that each specifically binds to an RNA-binding protein conjugated to a split fluorophore. When two genetically different genomes are within close proximity, the fluorophore halves come together to reconstitute fluorescence. These BiFC-labeled RNA dimers can be visualized and tracked in living cells and interact with retroviral Gag proteins. This method has the advantage of low background fluorescence and can be applied to the study of dimeric or double-stranded RNAs of viruses and other organisms. Full article

Infectious bronchitis virus (IBV) remains a major threat to poultry health worldwide due to frequent genetic changes mainly driven by recombination and limited cross-protection between genotypes. In this study, we analyzed IBV strains collected from clinical outbreaks in Chile between 1986 and 2021 to assess the long-term impacts of live-attenuated vaccines (Massachusetts and 4/91) on viral evolution. Phylogenetic analysis of the S1 and N genes revealed four major lineages circulating in Chile—GI-1, GI-13, GI-16, and a novel monophyletic clade we propose as GI-31. The latter, identified in isolates from 1986 to 1988, is highly divergent (22–24%) from other known lineages, representing a previously unreported South American IBV variant. Despite widespread Mass vaccination, genetically distinct field strains circulated during the 1980s, facilitating potential recombination with GI-1 vaccine-derived strains, including evidence of shared ancestry with GI-11, an endemic lineage from Brazil. Non-recombinant GI-16, likely introduced from Asia, was detected in isolates from 2009. Notably, a recombinant strain emerged in 2015, four years after 4/91 vaccine introduction, indicating vaccine–field-strain genetic exchange. By 2017, isolates with >99% identity to the 4/91 strain were recovered, suggesting vaccine-derived variants. In 2021, GI-1 re-emerged, showing recombination signatures between GI-1 and GI-13 (4/91-derived) strains, likely reflecting suboptimal or inconsistent vaccination strategies. Selection analyses showed strong purifying selection across most of the S1 gene, with limited sites under positive selection in the receptor-binding domain. Phylodynamic reconstruction revealed time-structured evolution and multiple introduction events over 35 years, with lineage-specific tMRCA estimates. Collectively, these findings highlight the emergence of a novel lineage in South America and demonstrate that vaccine use, while mitigating disease, has significantly shaped the evolution of IBV in Chile. Our results underscore the importance of continuous genomic surveillance to inform vaccine strategies and limit recombinant emergence. Full article

Background/Objectives: Colorectal cancer (CRC) is one of the most common malignancies worldwide. microRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally and have emerged as important regulators in cancer biology. This study aimed to investigate the roles of miR-379-5p and miR-519a-3p in CRC using Quantitative Real-Time PCR (RT-qPCR) and comprehensive bioinformatic analyses. Methods: Tumor tissues and matched adjacent normal tissues were collected from 54 patients with CRC. The expression levels of miR-379-5p and miR-519a-3p in these tissues were determined using the RT-qPCR method. To investigate the functional roles of differently expressed miRNAs, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to construct miRNA–transcription factor (TF)–target gene–disease interaction networks. Results: It was found that the expression level of miR-379-5p was statistically significantly increased in tumor tissues compared to normal tissues, while miR-519a-3p was decreased (p < 0.05). GO analysis revealed enrichment in several important biological processes, including cellular protein metabolic processes, biosynthetic processes, response to stress, and nucleic acid binding TF activity. KEGG analysis exhibited that dysregulated miRNAs were associated with important pathways related to carcinogenesis, such as p53 signaling, TGF-beta signaling, and FoxO signaling pathways. Additionally, the miRNAs-TFs-Genes-Diseases Networks analysis identified ESR1 and FOXA1 as common target TFs of dysregulated miRNAs. Network analyses showed that dysregulated miRNAs interact with CRC-associated genes (Caspase 3 (CASP3), Adenomatous polyposis coli (APC), and AKT serine/threonine kinase 3 (AKT3)). Conclusions: The present study indicates that miR-379-5p and miR-519a-3p may be involved in CRC progression, with miR-379-5p being upregulated and miR-519a-3p being downregulated in tumor tissues. However, further functional studies are required to clarify their potential roles in tumor biology. The findings of the study suggest that miR-379-5p and miR-519a-3p may be associated with regulatory pathways related to CRC. These miRNAs have the potential to serve as diagnostic biomarkers or therapeutic targets in CRC. Full article

The AP2/ERF (APETALA2/ethylene-responsive element binding factor) family represents one of the largest transcription factor families in plants, playing pivotal roles in abiotic stress responses and hormone signaling pathways. Through genome-wide analysis, we identified 163 AnAP2/ERF genes in Adiantum nelumboides. Transcriptome data revealed that 12 AnAP2/ERF genes were significantly upregulated under either drought or flooding stress, with 8 genes responding to both conditions. qRT-PCR validation confirmed that all 12 selected AnAP2/ERF genes exhibited differential expression under both stress types. Notably, these genes also showed significant induction by abscisic acid (ABA), auxin (IAA), and gibberellin (GA), suggesting their potential involvement in stress responses through hormone crosstalk. This study establishes a foundation for investigating AnAP2/ERF gene functions and their molecular mechanisms in abiotic stress adaptation in A. nelumboides. Full article

Calcium-dependent protein kinases (CDPKs) are unique serine/threonine kinases that play significant roles in response to environmental stresses in plants. In this study, we comprehensively characterized the CDPK gene family in the apple cultivar ‘Hanfu’ at the genome-wide level, and 38 MdCDPKs were identified. They were unevenly distributed across 14 chromosomes. Based on phylogenetic analysis, the MdCDPKs were classified into four subfamilies. Conserved domain analysis indicated that MdCDPKs contain the catalytic kinase domain and the Ca²⁺ binding domain. During Colletotrichum gloeosporioides infection, the expression level of MdCDPK24 was significantly upregulated. Subsequently, MdCDPK24 was fused to GFP to generate the MdCDPK24-GFP construct, and confocal microscopy imaging confirmed its cytoplasmic localization in Nicotiana benthamiana leaves. Using agrobacterium-mediated transformation, we generated the overexpression of MdCDPK24 transgenic calli. MdCDPK24-overexpressing calli demonstrated significantly reduced disease severity against C. gloeosporioides infection, indicating its positive role in apple bitter rot resistance. The analysis of the CDPK gene family in the apple cultivar ‘Hanfu’ provides a new insight into the identification of CDPK genes involved in biotic stress. MdCDPK24 represents a promising candidate for genetic manipulation to enhance apple bitter rot resistance. Full article

Heavy metal pollution, particularly copper contamination, threatens the ecological environment and human survival. In response to this pressing environmental issue, the development of innovative remediation strategies has become imperative. Bioremediation technology is characterized by remarkable advantages, including its ecological friendliness, cost-effectiveness, and operational efficiency. In our previous research, Rossellomorea sp. ZC255 demonstrated substantial potential for environmental bioremediation applications. This study investigated the removal characteristics and underlying mechanism of strain ZC255 and revealed that the maximum removal capacity was 253.4 mg/g biomass under the optimal conditions (pH 7.0, 28 °C, and 2% inoculum). The assessment of the biosorption process followed pseudo-second-order kinetics, while the adsorption isotherm may fit well with both the Langmuir and Freundlich models. Cell surface alterations on the Cu(II)-treated biomass were observed through scanning electron microscopy (SEM). Cu(II) binding functional groups were determined via Fourier transform infrared spectroscopy (FTIR) analysis. Simultaneously, the genomic analysis of strain ZC255 identified multiple genes potentially involved in heavy metal resistance, transport, and metabolic processes. These studies highlight the significance of strain ZC255 in the context of environmental heavy metal bioremediation research and provide a basis for using strain ZC255 as a copper removal biosorbent. Full article

Background/Objectives: The Fanconi anemia (FA) pathway is essential for the repair of DNA interstrand crosslinks and maintenance of genomic stability. Germline loss of FA pathway function in the inherited Fanconi anemia syndrome leads to increased DNA damage and a range of clinical phenotypes, including a heightened risk of head and neck squamous cell carcinoma (HNSCC). Non-synonymous FA gene mutations are also observed in up to 20% of sporadic HNSCCs. The mechanistic target of rapamycin (mTOR) is known to stimulate cell growth, anabolic metabolism including protein synthesis, and survival following genotoxic stress. Methods/Results: Here, we demonstrate that FA− deficient (FA−) HNSCC cells exhibit elevated intracellular amino acid levels, increased total protein content, and an increase in protein synthesis indicative of enhanced translation. These changes are accompanied by hyperactivation of the mTOR effectors translation initiation factor 4E Binding Protein 1 (4E-BP1) and ribosomal protein S6. Treatment with the mTOR inhibitor rapamycin reduced the phosphorylation of these targets and blocked translation specifically in FA− cells but not in their isogenic FA− proficient (FA+) counterparts. Rapamycin-mediated mTOR inhibition sensitized FA− but not FA+ cells to rapamycin under nutrient stress, supporting a therapeutic metabolism-based vulnerability in FA− cancer cells. Conclusions: These findings uncover a novel role for the FA pathway in suppressing mTOR signaling and identify mTOR inhibition as a potential strategy for targeting FA− HNSCCs. Full article

Skeletal muscle development is a critical economic trait in livestock, governed by myogenic satellite cell regulation. Integrins mediate mechanical anchorage to the ECM and enable ECM–intracellular signaling. CIB2, as an EF-hand-domain protein involved in mechanotransduction, shows significant developmental regulation in goat muscle. Although the role of CIB2 in skeletal muscle growth is poorly characterized, we observed pronounced developmental upregulation of IB2 in postnatal goat muscle. CIB2 expression increased >20-fold by postnatal day 90 (P90) compared to P1, sustaining elevation through P180 (p < 0.05). Functional investigations indicated that siRNA-mediated knockdown of CIB2 could inhibit myoblast proliferation by inducing S-phase arrest (p < 0.05) and downregulating the expression of CDK4/Cyclin D/E. Simultaneously, CIB2 interference treatment was found to decrease the proliferative activity of goat myogenic satellite cells, yet it significantly promoted differentiation by upregulating the expression of MyoD/MyoG/MyHC (p < 0.01). Mechanistically, CTCF was identified as a transcriptional repressor binding to an intragenic region of the CIB2 gene locus (ChIP enrichment: 2.3-fold, p < 0.05). Knockdown of CTCF induced upregulation of CIB2 (p < 0.05). RNA-seq analysis established CIB2 as a calcium signaling hub: its interference activated IL-17/TNF and complement cascades, while overexpression suppressed focal adhesion/ECM–receptor interactions and enriched neuroendocrine pathways. Collectively, this study identifies the CTCF-CIB2–integrin α7β1–PI3K/AKT axis as a novel molecular mechanism that regulates the balance of myogenic fate in goats. These findings offer promising targets for genomic selection and precision breeding strategies aimed at enhancing muscle productivity in ruminants. Full article

CNOT2, a central component of the CCR4-NOT transcription complex subunit 2, plays a pivotal role in the regulation of gene expression and metabolism. CNOT2 is involved in various cellular processes, including transcriptional regulation, mRNA deadenylation, and the modulation of mRNA stability. CNOT2 specifically contributes to the structural integrity and enzymatic activity of the CCR4-NOT complex with transcription factors and RNA-binding proteins. Recent studies have elucidated its involvement in cellular differentiation, immune response modulation, and the maintenance of genomic stability. Abnormal regulation of CNOT2 has been implicated in a spectrum of pathological conditions, including oncogenesis, neurodegenerative disorders, and metabolic dysfunctions. This review comprehensively examines the interplay between CNOT2 and p53, elucidating their collaborative and antagonistic interactions in various cellular contexts. CNOT2 is primarily involved in transcriptional regulation, mRNA deadenylation, and the modulation of mRNA stability, thereby influencing diverse biological processes such as cell proliferation, apoptosis, and differentiation. Conversely, p53 is renowned for its role in maintaining genomic integrity, inducing cell cycle arrest, apoptosis, and senescence in response to cellular stress and DNA damage. Emerging evidence suggests that CNOT2 can modulate p53 activity through multiple mechanisms, including the regulation of p53 mRNA stability and the modulation of p53 target gene expression. The dysregulation of CNOT2 and p53 interactions has been implicated in the pathogenesis and progression of various cancers, highlighting their potential as therapeutic targets. Additionally, CNOT2 regulates c-Myc, a well-known oncogene, in cancer cells. This review shows the essential roles of CNOT2 in maintaining cancer cellular homeostasis and explores its interactions within the CCR4-NOT complex that influence transcriptional and post-transcriptional regulation. Furthermore, we investigate the potential of CNOT2 as a biomarker and therapeutic target across various disease states, highlighting its significance in disease progression and treatment responsiveness. Full article

The recent discovery of Orthonairovirus songlingense (SGLV) and Norwavirus beijiense (BJNV) in China has raised significant concern due to their potential to cause severe human disease. However, little is known about the structural features and function of their nucleoproteins, which play a key role in the viral life cycle. By combining small-angle X-ray scattering (SAXS) data and AlphaFold 3 simulations, we reconstructed the BJNV and SGLV nucleoprotein structures for the first time. The SGLV and BJNV nucleoproteins have structures that are broadly similar to those of Orthonairovirus haemorrhagiae (CCHFV) nucleoproteins despite low sequence similarity. Based on structural analysis, several residues located in the positively charged region of BJNV and SGLV nucleoproteins have been indicated to be important for viral RNA binding. A positively charged RNA-binding crevice runs along the interior of the SGLV and BJNV ribonucleoprotein complex (RNP), shielding the viral RNA. Despite the high structural similarity between SGLV and BJNV nucleoprotein monomers, their RNPs adopt distinct conformations. These findings provide important insights into the molecular mechanisms of viral genome packaging and replication in these emerging pathogens. Also, our work demonstrates that experimental SAXS data can validate and improve predicted AlphaFold 3 structures to reflect their solution structure and also provides the first low-resolution structures of the BJNV and SGLV nucleoproteins for the future development of POC tests, vaccines, and antiviral drugs. Full article