Search PubMedSearch

SEARCH · Search PubMed

Results for “pan-IAV qPCR”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

80 records · Page 3Linked to original sources

Transcriptomic responses of Porphyrophora sophorae larvae during licorice root colonization reveal coordinated remodeling of translation, mitochondrial energy metabolism and defense-related genes.

BACKGROUND: Porphyrophora sophorae is a subterranean piercing-sucking scale insect that damages licorice (Glycyrrhiza uralensis) roots, but the molecular responses associated with larval root colonization remain insufficiently defined. METHODS: We compared non-parasitic larvae (NP) and root-colonizing larvae (RC) using six RNA-seq libraries, de novo transcriptome assembly, DESeq2-based differential expression analysis, GO/KEGG enrichment, annotation-based candidate gene screening, and RT-qPCR validation of selected genes. RESULTS: Sequencing yielded 260.91 million clean reads, and de novo assembly produced 60,794 non-redundant transcripts. DESeq2 identified 703 FDR-significant DEGs, including 49 upregulated and 654 downregulated genes in RC larvae. Upregulated genes were mainly associated with translation- and ribosome-related processes, whereas downregulated genes were enriched in mitochondrial, oxidation-reduction, energy metabolism, and oxidative phosphorylation-related functions. Annotation-based screening identified 75 FDR-significant candidate genes associated with chemosensation, defense-related responses, and energy metabolism, with mitochondrial energy metabolism-related genes forming the largest module. RT-qPCR validation based on the raw Ct data showed concordant expression directions for ten selected transcript targets. CONCLUSIONS: Root colonization in P. sophorae larvae was associated with coordinated transcriptional remodeling involving selective activation of translation-related processes, adjustment of mitochondrial energy metabolism, and changes in defense-related gene expression. These results provide candidate molecular targets for future functional studies of host contact, feeding establishment, and physiological adjustment in this subterranean scale insect.

Animals

Comparative transcriptomic analysis of the gills and hepatopancreas of freshwater-cultured Litopenaeus vannamei under chronic nitrite stress.

To investigate the differences in molecular responses between the gills and hepatopancreas of freshwater-cultured Litopenaeus vannamei under chronic nitrite stress, a 30-day chronic stress experiment was conducted with a control group and a stress group. Transcriptomic analysis of the gills and hepatopancreas was performed using Illumina sequencing; differentially expressed genes (DEGs) were identified, and GO, KEGG, GSEA, PPI, and RT-qPCR validation were carried out. The results showed that 196 DEGs (161 up-regulated and 35 down-regulated) were identified in the gills, and 287 DEGs (199 up-regulated and 88 down-regulated) in the hepatopancreas, with only 18 DEGs shared between the two tissues. DEGs in the gills were enriched in oxidoreductase activity, glycerophospholipid metabolism, and tyrosine metabolism; DEGs in the hepatopancreas were enriched in lipid transporter activity, phagosome, ECM-receptor interaction, and riboflavin metabolism. GSEA revealed significant suppression of the mTOR pathway in the gills and the Polycomb complex pathway in the hepatopancreas. PPI network analysis identified hub genes P5CS and eEF2 in the gills, and PER, TUBB1, SHMT, and TUBB4B in the hepatopancreas. RT-qPCR validation was consistent with the RNA-seq results (R2 = 0.764). This study indicates that, under chronic nitrite stress, the gill response is centered on redox regulation and inhibition of growth metabolism, whereas the hepatopancreas response primarily involves lipid transport, cytoskeletal remodeling, and phagosome activation. The two tissues synergistically adapt through fundamental biosynthetic and motor protein pathways. This research provides molecular evidence for deciphering the nitrite tolerance mechanisms in freshwater-cultured shrimp.

Animals

Estrone disrupts early reproductive development in juvenile male Siniperca chuatsi and is associated with brain and gonadal responses.

Whether estrone (E1)-associated disruption of early reproductive development in fish is accompanied by brain responses in addition to direct gonadal effects remains unclear. Here, juvenile Siniperca chuatsi, a non-model but economically important freshwater species, were exposed for 60 d to 0, 0.01, 0.1, and 1.0 μg/L E1, spanning environmentally reported and elevated concentrations. By integrating waterborne concentration monitoring, histopathology, transcriptomics, and quantitative real-time PCR (qPCR) validation, we evaluated E1-associated changes in brain and gonadal tissues during early reproductive development. Waterborne E1 concentrations remained generally stable throughout the exposure period. At the highest tested concentration (1.0 μg/L), E1 caused neuronal vacuolation and pyknosis in the hypothalamic region and induced distinct ovarian-like structures in the gonads of genetic males. In the brain, cyp19a1, crhr1, and adcy2a were significantly upregulated, whereas egr1 was significantly downregulated, indicating transcriptional changes in genes associated with local estrogen conversion, stress-response/cAMP signaling, and neuronal activity-related regulation within a broader injury/stress-response background. In the gonad, RNA-seq analysis showed significant downregulation of star2, hsd3b1, cyp17a1, and cyp11b and significant upregulation of hsd17b1, suggesting alterations in steroidogenesis-related gene expression at the transcriptomic level. qPCR analysis of selected gonadal candidate genes showed expression directions generally consistent with the RNA-seq results, and these molecular patterns were consistent with the feminized histological phenotype. Together, these results indicate that E1 can disrupt early reproductive development in juvenile S. chuatsi and support a cautious working model in which E1 exposure is accompanied by concurrent brain and gonadal responses. This study provides new evidence for understanding the toxic effects and ecological risk implications of natural estrogen E1 during early fish development.

Animals

ORBIT: Oncogenic Representation Learning via Bi-Prototype Contrastive Learning in Hyperbolic Space for cancer driver gene identification.

Accurate identification of cancer driver genes is crucial for precision oncology but remains challenging due to the complexity of integrating heterogeneous data and modeling dynamic biological systems. To address these limitations, we propose ORBIT (Oncogenic Representation Learning via Bi-Prototype Contrastive Learning in Hyperbolic Space). Our framework synergistically fuses multi-omics profiles with functional network data using a context-adaptive graph reweighting mechanism to capture cancer-specific dynamics. The model employs a bi-prototype contrastive learning strategy within hyperbolic space, which aligns gene representations around distinct driver and non-driver semantic anchors while preserving the intrinsic hierarchy of biological networks. Comprehensive evaluations demonstrate that ORBIT achieves highly competitive stability in pan-cancer analysis while consistently outperforming state-of-the-art methods in cancer-specific predictions. Furthermore, functional enrichment analysis confirms that the model effectively segregates core cancer pathways, and drug sensitivity profiling validates the clinical relevance of the identified drivers. By integrating hyperbolic geometry with context-adaptive learning, ORBIT offers a robust and interpretable paradigm for precision medicine. The source codes and datasets are publicly accessible at https://github.com/spcho-dev/ORBIT.

Humans

Dengue and chikungunya vaccines past, present and future: implications for travelers.

PURPOSE OF REVIEW: Novel vaccines for dengue and chikungunya viruses offer new prevention options against two globally important arboviral diseases. This review summarizes recent developments in vaccine licensure, implementation, real-world experience and research priorities, with emphasis on implications for both endemic populations and travelers. RECENT FINDINGS: Of the three live-attenuated dengue vaccines licensed to date, TAK-003 is authorized in >40 countries and Butantan-DV in Brazil, while manufacturing of CYD-TDV is discontinued. Long-term and postmarketing data continue to refine understanding of serotype-specific protection, waning immunity, and rare adverse events.For chikungunya, two single-dose vaccines are licensed-a live-attenuated vaccine (VLA1553) and virus-like particle vaccine (PXVX0317). Uptake is guided by emerging safety and effectiveness data, with each platform offering potential advantages in different settings.Further data on long-term protection, safety, effectiveness, use in vulnerable populations and integration into outbreak management and immunization systems is anticipated. SUMMARY: Dengue and chikungunya vaccines are increasingly being used in immunization programs and pretravel consultations. Further real-world data are needed-particularly for seronegative dengue vaccine recipients and older, immunocompromised or medically at-risk adults. Research priorities include developing single-dose, nonlive dengue vaccines suitable for high-risk groups, understanding long-term chikungunya vaccine performance, and exploring broader flaviviral or pan-arboviral platforms.

Humans

Dynamics of antibiotic resistance genes co-occurrence with pathogenic and non-pathogenic bacteria throughout wastewater treatment processes.

Wastewater treatment plants (WWTPs) are recognized hotspots for antibiotic resistance genes (ARGs) and pathogenic bacteria. Despite advancements in treatment technologies, the persistence of ARGs and pathogenic bacteria remains a concern. In this study, we analyzed the dynamic changes in ARGs and bacterial communities throughout the treatment processes within an anaerobic-anoxic-oxic (AAO) WWTP over one week by using HT-qPCR coupled with 16S rRNA gene amplicon sequencing. The connectedness index, based on network analysis, showed that the dynamics of ARGs and mobile genetic elements (MGEs) were more strongly associated with potentially pathogenic bacteria than with non-pathogenic bacteria, suggesting that ARG immigration and dissemination in the WWTP were likely driven by potentially pathogenic taxa. The AAO treatment significantly reduced ARGs in final effluent (EF) (∼64 %) and residual sludge (RS) (∼81 %); however, potential hosts of ARGs such as Comamonas testosteroni and Clostridioides difficile persisted with minimal changes in relative abundance and remained detectable in EF and RS. Notably, the abundance of ARGs was lower in RS than in EF, and source tracking analysis identified influent as the primary source of ARGs and potentially pathogenic taxa in EF, underscoring the greater health risks associated with effluent discharge.

Wastewater

Genome-wide identification and expression analysis of the CREB/ATF family and its potential role in melanogenesis in the Manila clam (Ruditapes philippinarum).

Ruditapes philippinarum is an economically important bivalve species in China, and shell color is a trait of ecological and commercial significance. Melanin is a key determinant of shell color, and members of the CREB/ATF family have been reported to participate in melanogenesis in other organisms. In this study, members of the CREB/ATF family were systematically identified at the whole-genome level based on genomic and transcriptomic datasets, followed by analyses of their phylogenetic relationships, gene structures, and expression patterns. A total of six CREB/ATF family members were identified and classified into five subfamilies. Expression profiling and RT-qPCR validation revealed that most CREB/ATF genes were highly expressed in the mantle and displayed clear differences among shell-color phenotypes. Except for RpATF4 and RpCREBZF, most members exhibited relatively high expression levels in dark-colored shell strains, particularly in black and zebra-striped clams. Moreover, most genes showed low expression during early embryonic and larval stages but increased expression at the single-siphon spat and juvenile stages. These results suggest that the CREB/ATF family may be involved in melanin-associated shell-color regulation in R. philippinarum, providing important candidate genes and a theoretical basis for further elucidating the molecular mechanisms of shell-color formation in mollusks.

Animals

Maize ZmMYB59 inhibits post-germinative shoot and root elongation through ZmGA2ox3/10-mediated gibberellin catabolism.

Gibberellin (GA) promotes seed germination, but sustained or excessive GA signaling after germination can lead to aberrant root and shoot elongation. How GA homeostasis is transcriptionally restrained during post-germinative seedling development remains unclear. Using overexpression and gene-edited maize materials, we demonstrate that ZmMYB59 inhibits root and shoot elongation during post-germinative growth. Integrated RNA-Seq and CUT&Tag analyses identified the GA catabolism genes ZmGA2ox3 and ZmGA2ox10 as candidate direct targets of ZmMYB59. Hormone profiling analysis showed elevated bioactive GA1 and GA4 levels in the scutellum and aleurone layer cells of zmmyb59 mutants. Dual-luciferase assays, electrophoretic mobility shift assays, and ChIP-qPCR further confirmed that ZmMYB59 directly binds AC8 cis-elements in the ZmGA2ox3/10 promoters and activates their transcription. The zmga2ox3/10 double mutant, but neither single mutant, exhibited enhanced root and shoot elongation, accompanied by GA4 accumulation. This phenotype was suppressed by exogenous application of the GA biosynthesis inhibitor uniconazole. Transcriptomic and biochemical analyses further revealed enhanced starch degradation, reduced starch content, and increased soluble sugar accumulation in the double mutant. Taken together, these findings reveal that the ZmMYB59-ZmGA2ox3/10 module restrains GA accumulation and starch mobilization after germination, thereby coordinating reserve utilization with post-germinative root and shoot growth in maize.

Gibberellins

Uncovering hidden complexity in the Apis mellifera mitotranscriptome: a polyadenylation-centered perspective.

Mitochondrial transcription is gaining increasing attention as researchers seek to better understand the full coding potential of mitochondrial DNA (mtDNA). Emerging evidence suggests that mtDNA may encode additional elements beyond classical oxidative phosphorylation genes, pointing to a more complex transcriptional architecture than previously recognized. In this study, we explored the mitochondrial transcriptome of Apis mellifera (Insecta: Hymenoptera), with a particular focus on polyadenylation-associated features. Our analysis revealed that both sense and antisense transcripts undergo polyadenylation, although transcript abundance and poly(A) tail lengths varied markedly across mitochondrial genes. Several transcripts exhibited alternative isoforms, either extended or truncated, frequently including intergenic regions. These regions may represent functional non-coding elements or structural variants rather than conventional untranslated regions (UTRs). Interestingly, some transcripts also contained non-templated nucleotide additions particularly cytosine residues immediately upstream of the poly(A) tails. Monocistronic units that included portions of downstream intergenic regions were among the most abundantly represented, suggesting a possible regulatory role for these sequences. To experimentally validate our in silico findings, we performed RT-qPCR to assess relative gene expression and applied 3' RACE-PCR to define transcript boundaries. These approaches confirmed the presence of multiple transcript isoforms and supported the involvement of polyadenylation in shaping mitochondrial RNA diversity. Together, our findings reveal a previously underappreciated level of complexity in the A. mellifera mitochondrial transcriptome and highlight the potential regulatory significance of polyadenylation dynamics and intergenic region transcription.

Animals

The circadian clock proteins PRR modulate root hair development via the RHD6/RSL module in Arabidopsis.

Root hairs, derived from trichoblasts, are critical for plant growth and environmental adaptation. Although environmental cues are known to influence root hair development, how endogenous timing systems such as the circadian clock integrate into the core transcriptional network governing root hair formation remains unclear. Here, we show that the circadian clock-associated protein PSEUDO-RESPONSE REGULATOR5 (PRR5) physically interacts with ROOT HAIR DEFECTIVE6 (RHD6) and RHD6 LIKE1 (RSL1), two basic helix-loop-helix transcription factors essential for root hair initiation. Genetic analyses suggest that PRR proteins contribute to root hair development under long-day conditions in Arabidopsis thaliana. Simultaneous disruption of PRR5, PRR7, and PRR9 results in defective root hairs, whereas PRR5 overexpression markedly increases root hair density and length. Transcriptomic and RT-qPCR analyses reveal that PRRs enhance the expression of RHD6, RSL1, and multiple downstream root hair-responsive genes, while modulating their temporal expression patterns. Furthermore, PRR5-mediated root hair promotion requires RHD6/RSL1, and PRR proteins enhance RHD6-dependent activation of the RSL4 promoter. PRRs also contribute to root hair development under phosphate-deficient and salt-stress conditions. Together, these findings establish a molecular framework in which PRR proteins regulate the RHD6/RSL network to coordinate root hair development and environmental responses.

Arabidopsis

Genome-wide identification and expression profiling of CSP and OBP genes in Stictocephala bisonia reveals candidate genes potentially associated with insecticide response.

Stictocephala bisonia is an important invasive agricultural pest. Due to the frequent application of insecticides in its habitat, this species is under intense selection pressure. Chemosensory proteins (CSPs) and odorant-binding proteins (OBPs) are known to play key roles in insecticide resistance, but their specific functions in S. bisonia remain unclear. In this study, we identified a total of 22 SbisCSPs and 16 SbisOBPs based on the S. bisonia genome. To screen for candidate genes potentially linked to insecticide resistance, we adopted a multi-criteria screening strategy that integrated phylogenetic analysis, molecular docking with three insecticides, and tissue-specific expression profiling. Phylogenetic analysis identified several SbisCSPs and SbisOBPs clustering with genes known to be involved in insecticide resistance, serving as an initial evolutionary filter. Molecular docking results indicated that λ-Cyhalothrin exhibited the strong predicted binding affinity with most of SbisCSPs and SbisOBPs. Subsequent qPCR validation of seven prioritized candidates revealed distinct expression patterns: SbisCSP22 was highly expressed in adults and demonstrated strong binding affinity to all three insecticides tested, suggesting a potential role in mediating multi-insecticide response. Conversely, SbisCSP17 was significantly upregulated in larvae, clustered with genes known to mediate imidacloprid resistance, and exhibited strong binding affinity to imidacloprid. Given its larval-specific expression and the soil-dwelling behavior of larvae, we hypothesize that SbisCSP17 is a key candidate gene for larvae coping with soil-treated insecticides.

Animals

The gonadal matrisome and its correlation with sex change in the ricefield eel Monopterus albus.

The matrisome is a comprehensive list of genes in the genome of an organism, which encodes proteins constituting or interacting with the extracellular matrix (ECM). The gonadal ECM is important for folliculogenesis and spermatogenesis. This study characterized the composition of the matrisome and the expression of matrisome genes in the gonad of ricefield eel, a protogynous sex-changing teleost, during sex change. A total of 838 matrisome genes were identified in the genome of ricefield eel through an in-silico orthology-based approach, of which 482, 443, 429, and 570 matrisome genes were shown to be expressed in the gonads of female (F), early intersexual (EI), mid-intersexual (MI), and late intersexual (LI) fish, respectively. Differentially expressed matrisome genes (DEMGs) were observed across all the sexual stages as well as in each category of ECM components. Analysis of DEMGs in the comparison between EI and F revealed dramatic upregulation of adam8a, mmp9, and s100a11 while downregulation of col4a5, col15a1b, clec3ba, f13a1, and ccl44, which were further confirmed by qPCR analysis. Together, these findings revealed significant changes in the expression of many matrisome genes, particularly three regulator genes, adam8a, mmp9 and f13a1, as female ricefield eels initiate sex change, suggesting that gonadal tissues undergo dramatic remodeling involving the regression of ovarian tissues and the development of testicular tissues to facilitate this process. These data provide valuable resources for further unraveling the roles of matrisome genes in gonadal development of ricefield eel and other vertebrates.

Animals

Genome-wide analysis of the plant-specific PLATZ gene family in Taraxacum kok-saghyz and its roles in response to drought and salt tolerance.

Abiotic stress severely limits plant growth and productivity. Taraxacum kok-saghyz Rodin (TKS), known for its environmental resilience, represents a valuable resource for identifying stress-tolerant genes to improve stress-adaptive crops. Plant AT-rich protein and zinc-binding protein (PLATZ) transcription factors serve as core regulators of plant growth, developmental processes, and adaptive responses to various stress conditions; however, they remain uncharacterized in TKS. Here, we identified 10 TksPLATZ genes through a whole-genome analysis. Phylogenetically, these genes were grouped into five distinct evolutionary branches. Promoter sequence analysis revealed multiple types of cis-acting regulatory elements that are connected with hormonal signal responses and environmental stress adaptation. Integrated analysis of transcriptome datasets and RT-qPCR validation demonstrated that TksPLATZ genes display tissue-specific expression profiles and show distinct responsive patterns to drought and salt stress treatments. Among them, TksPLATZ1, TksPLATZ2 and TksPLATZ7 were markedly induced under both stressors and were selected for further functional study. We demonstrated that TksPLATZ1, TksPLATZ2 and TksPLATZ7 localize to the cell nucleus and act as transcriptional activators and repressors, respectively. Phenotypic data from overexpression experiments in plants confirm that heterologous expression of TksPLATZ1, TksPLATZ2, and TksPLATZ7 enhances the tolerance of Arabidopsis to salt and osmotic stress. These findings provide valuable genetic resources for improving plant tolerance to environmental stresses.

Salt Tolerance

Genome-wide characterization of heat shock protein genes reveals thermal stress-responsive candidates in Litopenaeus vannamei.

Heat shock proteins (HSPs) are conserved molecular chaperones involved in protein folding, refolding, aggregation prevention, and degradation of damaged proteins. However, the genomic organization and thermal responsiveness of HSP genes in the Pacific white shrimp (Litopenaeus vannamei) remain incompletely understood. Here, we performed a genome-wide analysis of the HSP gene family and examined its phylogenetic relationships, structural features, duplication patterns, sequence variation, interaction networks, and transcriptional responses to acute heat stress. A total of 34 HSP genes were identified and classified into the HSP90, HSP70, HSP40/DNAJ, HSP60, and small HSP families. Phylogenetic, motif, gene structure, synteny, and subcellular localization analyses revealed evolutionary conservation and structural diversification among family members. Three duplicated gene pairs were identified, comprising two segmental duplications and one tandem duplication. All pairs exhibited Ka/Ks ratios below 1, consistent with purifying selection of varying strength. Sequence analysis identified 295 nonsynonymous single-nucleotide polymorphisms, of which 12 were consistently predicted to be deleterious by multiple algorithms. Protein-protein interaction analysis indicated enrichment of protein-folding and cellular stress-response functions. RT-qPCR analysis showed significant induction of HSPA4, HSP90AA1, TRAP1, BiP, and DNAJA1 after 6, 12, and 24 h of exposure to 34 °C, whereas DNAJC3 was significantly induced only at 12 h. All six genes reached their highest transcript abundance at 12 h. These findings may provide a genomic framework for HSP genes in L. vannamei and identify candidate genes and variants associated with thermal stress responses.

Animals

Genome-wide identification of the peanut HD-Zip gene family and AhHDZ15 positively regulating salt and drought stress in heterologously overexpressed Arabidopsis.

Homeodomain-leucine zipper (HD-Zip) transcription factors play important roles in plant growth, development, and abiotic stress responses. However, bioinformatic analyses and functional studies of HD-Zip family in peanut are scarce. In this study, 128 AhHDZ genes were identified and classified into four subfamilies in the phylogenetic analysis. Transcriptomic data and RT-qPCR analysis indicated the expression levels of AhHDZ4 and AhHDZ15 were significantly elevated in response to 12 h of salt stress, while AhHDZ4/15/60/69/126 all showed a progressive increase over time in response to drought stress. AhHDZ15 protein was localized in the nucleus. Under salt and drought stress, the germination rates of AhHDZ15-overexpressing in Arabidopsis were significantly higher than wild-type (WT), and root lengths were also significantly longer than WT. In addition, the SOD, CAT, chlorophyll content, and Relative Leaf Water Content (RLWC) value of leaves in AhHDZ15-overexpressing lines were significantly higher than WT, while the MDA content was significantly lower than WT. The above results indicate that heterologous overexpression of AhHDZ15 enhanced salt and drought tolerance in Arabidopsis. Furthermore, AhHDZ15 could bind to the L1-box element of the AhVNI2 promoter, thereby activating AhVNI2 transcription and enhancing the expression of downstream salt stress-responsive genes. These findings implies a potential function of AhHDZ15 in peanut that requires further validation.

Arabidopsis

Comprehensive identification and evolutionary analysis of the Wnt gene family in bivalves: Insights into the larval development of the noble scallop Chlamys nobilis.

The Wnt gene family regulates fundamental developmental processes in metazoans, but its evolutionary composition and developmental deployment in bivalves remain largely unresolved. Here, we performed a comparative genomic analysis of Wnt genes in 19 bivalve species and examined developmental expression profiles in the noble scallop Chlamys nobilis, with Crassostrea gigas and Chlamys farreri used for cross-species comparison. A total of 235 Wnt genes were identified and assigned to 12 subfamilies. No reliable Wnt3 ortholog was detected in any analyzed bivalve, supporting the view that Wnt3 loss occurred early during lophotrochozoan evolution rather than representing a lineage-specific absence. Most Wnt proteins retained the conserved WNT domain, indicating strong structural conservation, whereas lineage-specific copy-number variation and gene loss were observed among species. C. farreri and C. gigas each retained 12 Wnt genes and lacked Wnt3, whereas C. nobilis lacked Wnt3, Wnt7, and Wnt16. Developmental transcriptome analysis and RT-qPCR revealed clear stage-specific expression patterns. In C. gigas, Wnt2/10/A were highly expressed during earlydevelopment and peaked around the D-shaped larval stage, while Wnt8 and Wnt11 showed distinct stage-specific peaks. By contrast, Wnt1/5/6/9 were more active during later larval development or juvenile formation. These results provide a comparative framework for bivalve Wnt evolution and identify candidate Wnt genes potentially involved in larval development and aquaculture-relevant developmental transitions.

Animals

ChIP-seq profiling identifies diapause-regulated H3K27me3 targets in the fat body of Culex pipiens.

Culex pipiens, a principal vector of significant arboviruses, survives winter through diapause, a hormonally controlled inactive phase that enhances endurance under severe cold circumstances. Recent data suggests that epigenetic processes, namely histone post-translational modifications (hPTMs), play a crucial role in regulating seasonal dormancy. Prior studies from our laboratory indicated a decrease in the methylation of Histone 3 (H3K27me3) in diapausing fat body tissue, associated with elevated expression of the histone demethylase UTX. Nonetheless, the precise genomic areas impacted by these chromatin alterations remained unidentified. We used chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) to delineate the genome-wide distribution of H3K27me3 across fat body chromatin in diapausing (D) and non-diapausing (ND) female Cx. pipiens. Notably, the higher signal at transcription start sites (TSSs) reflects localized redistribution rather than a global decrease, as diapausing fat bodies retain less H3K27me3 overall but concentrate it at promoters. To investigate the functional significance of these chromatin alterations, we confirmed a number of target loci via ChIP-qPCR and assessed gene expression with qRT-PCR. We identified many critical genes that were markedly increased in diapausing mosquitoes, exhibiting an inverse relation to H3K27me3 enrichment. Our data demonstrates different H3K27me3 chromatin landscapes between diapausing and non-diapausing Cx. pipiens, corroborating a hypothesis of selective, locus-specific repression in the non-diapause state and its targeted removal during diapause to permit activation of dormancy-associated genes. These results suggest that chromatin remodeling is a core driver of the diapause switch.

Animals

Measurable Residual Disease and the Unresolved Biology of Leukemic Stem Cells.

Measurable residual disease (MRD) testing has transformed the management of hematologic cancers by enabling detection of residual malignant cells after therapy. Current approaches rely on qPCR and next-generation sequencing to monitor leukemia-associated somatic mutations, while multiparameter flow cytometry identifies aberrant leukemic immunophenotypes. Although these methods provide valuable prognostic and therapeutic information, MRD negativity remains an imperfect surrogate for cure. Most MRD platforms evaluate CD45+, rapidly dividing leukemic populations and fail to detect quiescent cells that may survive cytotoxic therapies which efficiently target proliferating hematopoietic cells. Relapse frequently occurs despite deep molecular remission, suggesting persistence of rare leukemic stem cells (LSCs) that are intrinsically resistant to chemotherapy and targeted therapies. The paradox of relapse despite molecular remission could be explained by the presence of very small embryonic-like stem cells (VSELs) which are pluripotent, quiescent stem cells sitting at the top of cellular hierarchy in multiple adult tissues including bone marrow. A pluripotent VSEL divides through asymmetrical cell division to give rise to two cells of different sizes and fates, smaller cell is to self-renew while the bigger is lineage-restricted and tissue-committed progenitor which undergoes extensive epigenetic changes, divides rapidly and undergoes clonal expansion before further differentiation. Dysfunctions of VSELs initiate both solid and hematologic cancers. Based on this view, somatic mutations monitored during MRD assessment possibly represent downstream consequences of clonal expansion rather than the initiating drivers of disease persistence. Thus, exclusive monitoring of somatic mutations and CD45 + leukemic populations possibly overlook rare, small-sized, CD45- VSELs that contribute to therapeutic resistance and relapse.

Humans