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AKR7A3 rs1738023 association with susceptibility to female hepatocellular carcinoma and its role in AFB1 metabolism and tumor.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common cancer worldwide. In this study, we performed a two-stage exome-chip association analysis and found that the aldo-keto reductase family7 member A3 (AKR7A3) rs1738023 may be a potential susceptibility locus for HCC in females. We aimed to explore its role and mechanism. METHODS: The association between genotype and phenotype was analyzed through GWAS method. The expression of AKR7A3 in cancer tissue and blood analysis by qRT-PCR. The relationship of AKR7A3 and aflatoxin B1 (AFB1) was also analyzed. The effect of AKR7A3 on the biological behavior of HCC cell line was investigated on proliferation and invasion. The potential mechanism was analyzed by transcriptome analysis and western blot. RESULTS: Through genome-wide association analysis (GWAS), AKR7A3 (rs1738023), KIF2C (rs4342887), and CYP3A5 (rs6977165 and rs4646450) were found to be associated with susceptibility to hepatocellular carcinoma (HCC) in women. Further expression quantitative trait loci (eQTL) analysis showed that only AKR7A3 (rs1738023) was significantly associated with gene expression. The expression of AKR7A3 was significantly lower in HCC than adjacent non-tumorous tissues (P&#x2009;<&#x2009;0.001). The genotype of rs1738023 was significantly associated with AKR7A3 expression (P&#x2009;=&#x2009;0.0085). Rs1738023[C] genotype had a low AKR7A3 expression level and limited detoxification ability of AFB1. Literature data showed that AKR7A3 is involved in the metabolism of aflatoxin B1 (AFB1). Functional experimental results showed that overexpression of AKR7A3 in the normal liver cell line HL-7702 could significantly reduce AFB1-induced ROS levels and DNA adduct formation, suggesting that it plays a protective role in AFB1 metabolic detoxification. Cell function test showed that overexpression of AKR7A3 inhibit the proliferation, migration and invasion of HCC cells, and block the cell cycle. Transcriptome sequencing and KEGG pathway enrichment analysis revealed that overexpression of AKR7A3 affected the PI3K signaling pathway and led to downregulation of HIF1A and its downstream VEGFA protein expression. The validation results were confirmed in HCC cell lines Huh-7 and SUN-387. CONCLUSION: Overexpression of AKR7A3 contributes to inhibition of HCC progression and reduction of aflatoxin toxicity. AKR7A3 may serve as a potential prognostic and therapeutic target for HCC patients, although further validation is needed.

AKR7A3↗

The maternal-to-zygotic transition is a critical window for PFOA-induced disruption of developmental programming.

Early embryogenesis is governed by precisely timed gene regulatory programs that coordinate cell fate specification, tissue patterning, and morphogenesis. The maternal-to-zygotic transition (MZT) represents a pivotal developmental milestone during which regulatory control shifts from maternally deposited transcripts to activation of the zygotic genome. Disruption of this transition has the potential to alter developmental trajectories with lasting consequences. Per- and polyfluoroalkyl substances (PFAS), environmentally persistent contaminants, have been linked to developmental abnormalities, yet their impact on core embryonic gene regulatory networks especially with exposure during MZT is not well understood. Using zebrafish (Danio rerio), a tractable vertebrate model and New Approach Methodology (NAM), we investigated how PFAS exposure during the MZT alters early developmental programming. Embryos were exposed starting at different times before and within the MZT time window and collected at 24&#xa0;h post-fertilization (hpf) for transcriptomic analysis. Targeted qRT-PCR revealed dysregulation of genes controlling transcriptional activation, lineage specification, proliferation, and differentiation. Whole-transcriptome RNA sequencing (RNA-seq) further identified widespread perturbations in gene networks governing transcriptional regulation, cell signaling, and embryonic morphogenesis. Temporal analysis revealed that exposure beginning at 3.5&#xa0;hpf, followed by 8&#xa0;hpf, corresponding to early zygotic genome activation and near completion of zygotic activation, respectively, resulted in the greatest differential gene expression changes at 24&#xa0;hpf. Consistent with these early gene regulatory perturbations, larvae exposed starting at 8&#xa0;hpf also exhibited altered behavior at 5&#xa0;days post-fertilization. Together, these findings demonstrate that PFAS exposure during MZT disrupts the establishment of embryonic gene regulatory networks, linking environmental toxicant exposure to altered developmental patterning and organismal outcomes. This work underscores the vulnerability of early developmental transitions to environmental perturbation and positions MZT as a critical window of susceptibility during development.

NAMs (new approach methodologies)↗

Combined transcriptome and proteome analysis of Escherichia coli during high cell density culture.

Combined transcriptome and proteome analysis was carried out to understand metabolic and physiological changes of Escherichia coli during the high cell density cultivation (HCDC). The expression of genes of TCA cycle enzymes, NADH dehydrogenase and ATPase, was up-regulated during the exponential fed-batch period and was down-regulated afterward. However, expression of most of the genes involved in glycolysis and pentose phosphate pathway was up-regulated at the stationary phase. The expression of most of amino acid biosynthesis genes was down-regulated as cell density increased, which seems to be the major reason for the reduced specific productivity of recombinant proteins during HCDC. The expression of chaperone genes increased with cell density, suggesting that the high cell density condition itself can be stressful to the cells. Severe competition for oxygen at high cell density seemed to make cells use cytochrome bd, which is less efficient but has a high oxygen affinity than cytochrome bo(3). Population cell density itself strongly affected the expression of porin protein genes, especially ompF, and hence the permeability of the outer membrane. Expression of phosphate starvation genes was most strongly up-regulated toward the end of cultivation. It was also found that sigma(E) (rpoE) plays a more important role than sigma(S) (rpoS) at the stationary phase of HCDC. These findings should be invaluable in designing metabolic engineering and fermentation strategies for the production of recombinant proteins and metabolites by HCDC of E. coli.

Amino Acid Sequence↗

Early granuloma formation after aerosol Mycobacterium tuberculosis infection is regulated by neutrophils via CXCR3-signaling chemokines.

Among the first cells to invade a site of infection, polymorphonuclear neutrophils (PMN) play an important role in the control of numerous infections. While PMN are considered critical for control of acute infections, their role in chronic infections remains less well understood. Here we report that PMN are essential for accurate early granuloma formation during chronic M. tuberculosis infection without influencing mycobacterial growth restriction. The PMN-mediated regulation of granuloma formation depended on chemokines signaling through CXCR3, in particular MIG, as indicated by immune histochemical analysis of lung sections from C57BL/6 wild-type and CXCR3(-/-) mutant mice and supported by microarray transcriptome analysis. Hence, PMN play a central role in regulating the focal granulomatous response in the lung, and this early granuloma formation can be segregated from long-term protection against pulmonary M. tuberculosis infection.

Aerosols↗

Transcriptomic insights into temperature regulation of proliferation and differentiation in skeletal muscle cells of Nibea albiflora.

Myogenesis involves sequential stages of muscle satellite cell activation, myoblast proliferation, differentiation, and fusion into multinucleated myotubes. Teleost muscle exhibits indeterminate growth and is highly sensitive to environmental temperature, yet the underlying mechanisms by which temperature regulate proliferation and differentiation remain poorly understood. In this study, we established a primary skeletal muscle cell culture from the yellow drum (Nibea albiflora), an economically important marine fish, and integrated morphological observations with comparative transcriptomics analysis to characterize cellular and molecular responses at 28&#xa0;&#xb0;C and 20&#xa0;&#xb0;C during both proliferation and differentiation stages. Phenotypic analysis revealed that 28&#xa0;&#xb0;C significantly enhanced both myoblast proliferation and myogenic differentiation ability compared with 20&#xa0;&#xb0;C. Transcriptomic profiling revealed that at 28&#xa0;&#xb0;C, differentiation upregulated extracellular matrix(ECM) organization, calcium signaling, and sarcomere assembly, while proliferation enhanced focal adhesion, growth factor signaling, and lipid metabolism. At 20&#xa0;&#xb0;C, differentiation was characterized by glutathione metabolism, and ferroptosis, while proliferation involved cytokine-cytokine receptor interaction and negative regulation of signal transduction. Core myogenic regulatory factors (MRFs), particularly myogenin, were strongly upregulated at 28&#xa0;&#xb0;C during the differentiation stage, serving as an internal control. Based on these findings, we propose a testable model that elevated temperature coordinates Ca2+-dependent MRF activation with ECM-integrin signaling to drive sarcomere assembly and muscle growth. Key differentially expressed genes (DEGs) regulating myogenesis in N. albiflora were also identified. This study provides a mechanistic framework for temperature adaptation in teleost skeletal muscle and identifies candidate genes for functional validation and marker-assisted selection, as well as a rationale for temperature management strategies to improve aquaculture yield of N. albiflora.

Animals↗

A functional genomics approach toward the understanding of secondary metabolism in plant cells.

Despite the tremendous importance of secondary metabolites for humans as for the plant itself, plant secondary metabolism remains poorly characterized. Here, we present an experimental approach, based on functional genomics, to facilitate gene discovery in plant secondary metabolism. Targeted metabolite analysis was combined with cDNA-amplified fragment length polymorphism-based transcript profiling of jasmonate-elicited tobacco Bright yellow 2 cells. Transcriptome analysis suggested an extensive jasmonate-mediated genetic reprogramming of metabolism, which correlated well with the observed shifts in the biosynthesis of the metabolites investigated. This method, which in addition to transcriptome data also generates gene tags, in the future might lead to the creation of novel tools for metabolic engineering of medicinal plant systems in general.

Acetates↗

Identifying key palmitoylation-associated genes in endometriosis through genomic data analysis.

BACKGROUND: Palmitoylation, a post-translational lipid modification, has garnered increasing attention for its role in inflammatory processes and tumorigenesis. Emerging evidence suggests a potential association between palmitoylation and inflammatory responses in the pathogenesis of endometriosis. However, the precise mechanistic interplay remains elusive, necessitating further investigation. METHODS: This study integrated transcriptomic analysis and Mendelian randomization (MR) to identify a causal gene set implicated in endometriosis. Differentially expressed genes (DEGs) were first identified in the training dataset using the limma package in R. Weighted gene co-expression network analysis (WGCNA) was subsequently performed, leveraging Single Sample Gene Set Enrichment Analysis (ssGSEA)-derived scores of palmitoylation-related genes (PRGs) as phenotypic traits to identify key modular genes. The intersection of these key modular genes with DEGs yielded a refined gene set. Machine learning algorithms were then applied to further optimize gene selection, followed by external validation, immune infiltration analysis, RNA network construction, and exploration of potential targeted drug candidates. RESULTS: Through a rigorous screening process, VRK1, GALNT12, and RMI1 emerged as key genes associated with palmitoylation, exhibiting significant downregulation in endometriosis samples (P <&#x2009;0.05), indicative of a potential protective role. Immune infiltration analysis further revealed strong correlations between these genes and M2 macrophages as well as resting Natural Killer (NK) cells. Additionally, investigations into the targeted RNA network and drug association profiling provided novel insights, laying the groundwork for future high-quality validation studies. CONCLUSIONS: This study employed a comprehensive analytical framework to identify palmitoylation-associated key genes in endometriosis. The integration of immunoinfiltration analysis, RNA network construction, and drug association profiling offers valuable insights for advancing clinical diagnostics, disease monitoring, and therapeutic development in endometriosis.

Humans↗

CD40 transcriptomic expression patterns across malignancies: implications for clinical trials of CD40 agonists.

BACKGROUND: CD40 is a T-cell co-stimulatory receptor targeted by next-generation immunotherapies. We conducted a pan-cancer transcriptome analysis of CD40, its ligand, and related immune markers to evaluate co-expression patterns and clinical outcomes. METHODS: We analyzed transcriptome data for CD40, its ligand, and other common checkpoints and co-stimulators (PD-1, PD-L1, PD-L2, CTLA-4, LAG-3, ICOS, CD27, CD28, OX40, and GITR). RNA expression was classified as high (75-100th percentile), moderate (25-74th), or low (0-24th) against a reference population of 735 previously tested solid tumors. RESULTS: Of 514 patients, 114 (22%) showed high, 247 (48%) moderate, and 153 (30%) low CD40 RNA expression. High CD40 expression was most frequent in liver and bile duct (42%), pancreatic (42%), and ovarian (40%) cancers. Both high CD40 and low-moderate CD40 ligand expression-potentially conducive to CD40 agonist therapy-was most frequent in ovarian (33%) and pancreatic (24%) cancer. In both UCSD (N&#x2009;=&#x2009;514) and TCGA (N&#x2009;=&#x2009;10,953) cohorts, high CD40 expression significantly correlated with high CD28 and GITR. High CD40 RNA levels were not prognostic for overall survival (OS) from metastatic disease (P&#x2009;=&#x2009;0.2) (n&#x2009;=&#x2009;272 immune checkpoint inhibitor (ICI)-na&#xef;ve patients). High CD40 expression correlated with longer OS from immunotherapy initiation (n&#x2009;=&#x2009;217 ICI-treated patients; P&#x2009;=&#x2009;0.04, univariable analysis), but not multivariable analysis, suggesting it may not be an independent predictive biomarker. CONCLUSION: High CD40 expression correlated with liver and bile duct, pancreatic, and ovarian cancers, as well as with CD28 and GITR transcripts. Immune marker co-expression in individual patients merits further exploration for the development of CD40-based and other immunotherapy interventions.

Humans↗

ceRNA network of lncRNAs and mRNAs in OSF-to-OSCC progression: Diagnostic biomarkers and functional pathways.

BACKGROUND: Oral submucous fibrosis (OSF) is a chronic potentially malignant disorder that can progress to oral squamous cell carcinoma (OSCC). Although dysregulated non-coding RNAs have been implicated in oral carcinogenesis, the competing endogenous RNA (ceRNA)-mediated regulatory mechanisms underlying OSF-to-OSCC progression remain poorly understood. This study aimed to identify candidate regulatory molecules and construct a putative lncRNA-miRNA-mRNA network associated with malignant transformation. METHODS: Publicly available microarray datasets (GSE117973 and GSE125866) were analyzed to identify differentially expressed genes between OSF and OSCC. Differentially expressed transcripts were classified into mRNAs and lncRNAs based on public transcript annotations. Highly correlated lncRNA-mRNA pairs were identified using Pearson correlation analysis and integrated with multiMiR-supported miRNA-mRNA interactions obtained from public databases to construct a putative ceRNA regulatory network. Functional characterization focused on apoptosis, epithelial-mesenchymal transition (EMT), and immune checkpoint-related pathways. Receiver operating characteristic (ROC) analysis was performed to evaluate diagnostic performance, and selected biomarkers were externally validated using The Cancer Genome Atlas (TCGA) OSCC cohort. RESULTS: Integrated transcriptomic analysis identified several dysregulated mRNAs and lncRNAs associated with OSF-to-OSCC progression. Network analysis highlighted TBC1D3B, RREB1, TEAD3, SREBF1, TMEM41B, FOXK2, and KIAA1958 as prominent hub genes within the putative regulatory network. Functional analyses demonstrated significant associations with apoptosis-, EMT-, and immune checkpoint-related genes, suggesting potential involvement in multiple biological processes contributing to malignant transformation. Several hub genes exhibited strong diagnostic performance, with ROC analysis yielding AUC values ranging from 0.891 to 1.000, indicating excellent discrimination between OSF and OSCC samples. External validation using TCGA further supported the relevance of the identified biomarkers in OSCC. CONCLUSIONS: This study provides a comprehensive transcriptomic framework describing putative lncRNA-miRNA-mRNA regulatory interactions associated with OSF progression to OSCC. The identified hub genes and regulatory networks represent candidate biomarkers for early detection and provide a foundation for future mechanistic and experimental validation. As the proposed ceRNA interactions are computationally inferred, further biological validation is required before clinical application.

RNA, Long Noncoding↗

An intermediate activation state primes Langerhans cell migration from the epidermis.

Langerhans cells (LCs) are a specialized subset of dendritic cells in the epidermis, forming a dense network that acts as a frontline defense through immune surveillance. Upon antigen uptake, LCs become activated and orchestrate subsequent immune responses by migrating to lymphatics. However, how transcriptional programs are regulated during activation and how LCs behave in vivo during this transition remain poorly understood. Here, we combine single-cell transcriptomic analysis and intravital imaging to reconstruct the activation trajectory of epidermal LCs. We present a high-resolution single-cell transcriptomic dataset of over 22,000 high-quality epidermal LCs in both homeostatic and injured conditions. We define specific LC subpopulations representing sequential activation stages, characterized at the level of pathways and transcription factors. Notably, we identify a distinct intermediate state that precedes their migration. Integrating our data with an external dataset from homeostatic and injured skin reveals that wound-specific, WNT-modulated fibroblasts are the primary source of C3, the central component of the complement cascade. Intravital imaging of C3-deficient mice demonstrated that C3 is essential for effective recruitment of activated LCs to wound sites. Together, our findings uncover a novel population of activated epidermal LCs and highlight complement signaling as a critical mediator of LC recruitment during skin injury.

Activation↗

Distinct spatial transcriptomic patterns of substantia Nigra in Parkinson disease and Parkinsonian subtype of multiple system atrophy.

To investigate transcriptomic signatures of Parkinson's disease (PD) and the Parkinsonian subtype of Multiple System Atrophy (MSA-P) in substantia nigra pars compacta (SNpc), we conducted transcriptome analysis using in-situ hybridization on paraffin-embedded SNpc tissues from post-mortem brains. The study included 2 MSA-P patients, 2 PD patients, and 2 healthy controls (HC), with 12 regions of interest (ROIs) selected from the dorsal to ventral and medial to lateral aspects of the SNpc. A total of 72 ROIs from 6 participants were analyzed, and differentially expressed genes (DEGs) were identified by comparing MSA-P, PD and HC groups. The MSA-P group showed 88 upregulated DEGs and 326 downregulated DEGs (adjusted &#x1d45d;<0.05) compared to HC. The downregulated DEGs were significantly enriched in pathways related to ribosomal translation, immune processes, mitochondrial function, and autophagy. Notably, the dorsomedial quadrant was uniquely linked to antigen presentation, while other quadrants showed downregulation of protein synthesis. The PD group exhibited 165 upregulated DEGs and 350 downregulated DEGs (adjusted &#x1d45d;<0.05) compared to HC, with downregulated DEGs associated with ribosomal translation, mitochondrial function, and the ubiquitin-proteasome system. In both MSA-P and PD, the upregulated DEGs were not associated with any pathways or biological process in gene enrichment analysis. In network propagation analysis, amyloid precursor protein was the most significant network hub among DEGs in both MSA-P and PD. Comparing the transcriptomic signatures of SNpc between MSA-P and PD, we found immune/inflammation, mitochondrial function and neural signaling related genes were significantly downregulated in MSA-P compared to PD. Overall, the transcriptomic signature of the SNpc in MSA-P and PD revealed overlapping but distinct features, including alterations in protein synthesis, immune processes, mitochondrial function, and protein degradation systems. Future studies with larger cohorts and functional validation are needed to further elucidate these findings.

Humans↗

Multi-omics integration uncovers adaptive responses of stomach and pyloric ceca to artificial feed in mandarin fish (Siniperca chuatsi).

The mandarin fish, as an obligate piscivore, is highly dependent on live bait, which restricts its intensive aquaculture. Although domestication has enabled it to partially accept formulated diets, the tissue-specific molecular adaptation mechanisms of its digestive tract to artificial feed remain unclear. In this study, we conducted an integrated analysis of mandarin fish fed with live bait or artificial diet for three weeks, combining growth performance evaluation, gastric histology, and paired transcriptomic and metabolomic analyses of the stomach and pyloric ceca. AD feeding significantly improved growth performance, while histological examination revealed marked hyperplasia of the gastric mucosa and disorganized fold structures. Transcriptomic analysis identified 5065 and 3381 differentially expressed genes in the stomach and pyloric ceca, respectively. In the stomach, the artificial diet induced a glutathione-dependent antioxidant response, accompanied by glycolytic reprogramming and coordinated upregulation of genes in the extracellular matrix (ECM)-receptor interaction signaling pathway, including those encoding collagen, laminin, and integrin. In the pyloric ceca, the tricarboxylic acid (TCA) cycle and oxidative phosphorylation were broadly suppressed, whereas glycosaminoglycan degradation and lysosomal pathways were activated. Metabolomic analysis showed that gastric metabolites were enriched in vascular and inflammatory mediator pathways, while metabolites in the pyloric ceca were enriched in peroxisome proliferator-activated receptor (PPAR) signaling, sphingolipid signaling, and steroid hormone biosynthesis pathways. Following artificial diet feeding, integrated multi-omics analysis of the stomach revealed significant enrichment of pathways such as phospholipase D signaling, sphingolipid signaling, and arachidonic acid metabolism, accompanied by the accumulation of key metabolites including sphingosine-1-phosphate, 20-hydroxyeicosatetraenoic acid, and cellobiose. Integrated analysis of the pyloric ceca identified significantly altered pathways, including sphingolipid metabolism, alpha-linolenic acid metabolism, and glutathione metabolism, along with elevated levels of sphingosine-1-phosphate, sphingosine galactoside, and 9-hydroxy-12-oxo-10,15-octadecadienoic acid, as well as decreased glutathionylspermidine. These findings systematically unveil the tissue-specific molecular adaptation characteristics of the mandarin fish digestive tract in response to artificial feed, providing an important basis for understanding the molecular mechanisms of dietary adaptation in carnivorous fish and for optimizing artificial feed formulations.

Animals↗

Yeast HAT1 and HAT2 deletions have different life-span and transcriptome phenotypes.

HAT-B is a yeast histone acetyltransferase composed of Hat1, Hat2 and Hif1 proteins. We demonstrate that a hat2 mutant or a hat1hat2 double mutant, but not a hat1 mutant, have an extended life-span. Transcriptome analysis shows that the single hat mutants are not very different from wild type. However, the comparison of the hat1 and hat2 transcriptomes shows that they are different. The hat1hat2 double mutant shows a transcriptional phenotype similar to that of the hat1 mutant but strongly enhanced. These results indicate that Hat2p could have additional functions in the cell to those of Hat1p.

Acetyltransferases↗

Light, the circadian clock, and sugar perception in the control of lignin biosynthesis.

Experiments were undertaken to investigate some of the mechanisms that may function to regulate lignin biosynthesis (lignification) in Arabidopsis thaliana. Northern blot analyses revealed that several genes encoding enzymes involved in the synthesis of lignin monomers displayed significant changes in transcript abundance over a diurnal cycle. Northern blot analysis also suggested that some of the changes in diurnal transcript abundance were likely to be attributable to circadian regulation, whereas others were likely to be attributable to light perception. Comparison of circadian changes in transcript abundance of lignin biosynthetic genes between wild-type plants and the sex1 mutant, which is impaired in starch turnover, suggested that carbon availability related to starch turnover might determine the capacity to synthesize lignins. This hypothesis was supported by the observation that the sex1 mutant accumulated fewer lignins than wild-type plants. Consistent with the relationship between carbon availability and lignin accumulation, analysis of dark-grown wild-type A. thaliana seedlings uncovered a role for sugars in the regulation of lignin biosynthesis. Analysis of lignin accumulation, as determined by qualitative changes in phloroglucinol staining, suggested that metabolizable sugars positively influence the abundance of lignins. Transcriptome analysis supports the hypothesis that sugars are not merely a source of carbon skeletons for lignification, but they also function as a signal to enhance the capacity to synthesize lignins.

Arabidopsis↗

Selective saccular plasticity under microgravity links peripheral transcriptomic remodeling to postflight vestibular dysfunction.

Long-duration exposure to microgravity disrupts human balance and spatial orientation, yet the molecular mechanisms underlying vestibular adaptation to spaceflight remain poorly understood. Here, we tested the hypothesis that the saccule, the primary gravity-sensing otolith organ, undergoes selective remodeling during spaceflight and contributes to transient postflight postural instability. Using a cross-species approach, we combined transcriptomic analysis of mouse otolith organs with physiological assessments in astronauts. Laser microdissection-based RNA sequencing of mouse otolith sensory epithelia after a 35-d spaceflight revealed pronounced, organ-specific transcriptomic remodeling in the saccule, whereas the utricle remained stable. Principal component and clustering analyses demonstrated that the saccular transcriptome shifted toward an utricle-like profile under microgravity, accompanied by changes in genes related to synaptic and neuronal function. Promoter motif analysis identified NFAT-associated transcriptional networks, suggesting Ca2+-dependent regulation of synaptic plasticity as a potential molecular substrate of gravity-dependent adaptation. In parallel, vestibular testing in astronauts following long-duration missions (157 to 328 d) revealed selective attenuation of saccule-mediated cervical vestibular-evoked myogenic potentials and increased postural sway immediately after return to Earth, while utricle-mediated responses and semicircular canal function were preserved. Both saccular function and postural stability recovered within approximately 10 d. Notably, early postflight postural instability was partially mitigated by noisy galvanic vestibular stimulation, consistent with stochastic resonance-mediated sensory enhancement. Together, these findings identify the saccule as a plastic gravity sensor and establish a mechanistic link between peripheral molecular remodeling and functional balance deficits after spaceflight, providing a framework for developing countermeasures to facilitate vestibular readaptation during human space exploration.

Animals↗

Transcript profiling of Eucalyptus xylem genes during tension wood formation.

Tension wood formed in response to gravitational force is a striking example of the plasticity of angiosperm wood. In this study our goal was to characterize the early changes in gene expression during tension wood formation in Eucalyptus. Using cDNA array technology, transcript profiling of 231 genes preferentially expressed in differentiating Eucalyptus xylem was followed from 6 h to 1 wk of a tension time course of artificially bent Eucalyptus trees. 196 genes were differentially regulated between control and bent trees, some exhibiting distinctive expression patterns related to changes in secondary cell wall structure and composition. For instance, expression of a cellulose synthase gene was well correlated with the appearance of the G-layers. Cluster correlation analysis revealed differential regulation of lignin biosynthetic genes and may also be used to help infer the function of unknown gene products. Eucalyptus wood transcriptome analysis during tension wood formation not only provided new clues into the transcriptional regulatory network of genes preferentially expressed in xylem, but also highlighted candidate genes responsible for the genetic and environmentally induced variation of wood quality traits.

Biomechanical Phenomena↗

Construction and usage of a onefold-coverage shotgun DNA microarray to characterize the metabolism of the archaeon Haloferax volcanii.

Haloferax volcanii is a moderately halophilic archaeon that can grow aerobically and anaerobically with a variety of substrates. We undertook a novel approach for the characterization of metabolic adaptations, i.e. transcriptome analysis with a onefold-coverage shotgun DNA microarray. A genomic library was constructed and converted into a polymerase chain reaction (PCR) product library, which was used to print two DNA microarrays, a 960-spot test array used for optimization of microarray analysis and a 2880-spot onefold-coverage array. H. volcanii cultures were shifted from casamino acid-based metabolism to glucose-based metabolism, and the transcriptome changes were analysed with the onefold-coverage array at five time points covering the transition phase and the onset of exponential growth with the new carbon source. About 10% of all genes were found to be more than 2.5-fold regulated at at least one time point. The genes fall into five clusters of kinetically co-regulated genes. For members of all five clusters, the results were verified by Northern blot analyses. The identity of the regulated genes was determined by sequencing. Many co-regulated genes encode proteins of common functions. Expected as well as a variety of unexpected findings allowed predictions about the central metabolism, the transport capacity and the cellular composition of H. volcanii growing on casamino acids and on glucose. The microarray analyses are in accordance with the growth rates and ribosome contents of H. volcanii growing on the two carbon sources. Analysis of the results revealed that onefold-coverage shotgun DNA microarrays are well suited to characterize the regulation of metabolic pathways as well as protein complexes in response to changes in environmental conditions.

Gene Expression Profiling↗

Multi-omics analysis reveals stage-associated differences in gut immunity and microbiota between juvenile and adult common carp (Cyprinus carpio).

In vertebrates, the development of intestinal immunity is closely associated with dynamic changes in the gut microbiota. However, stage-associated differences in intestinal immunity and gut microbial communities remain poorly characterized in teleost fish. In this study, transcriptomic analysis combined with 16S rRNA gene sequencing was employed to characterize intestinal immunity and gut microbial communities in juvenile and adult common carp (Cyprinus carpio). Transcriptomic profiling revealed marked developmental differences in intestinal immune function. Juvenile carp exhibited a predominantly innate immune phenotype, characterized by elevated expression of pro-inflammatory cytokines, antimicrobial peptides, and lysozyme-related genes. This immune profile was accompanied by enhanced mucosal barrier function and a relatively pro-inflammatory intestinal environment. In contrast, adult carp displayed increased expression of genes associated with adaptive immunity, suggesting that adult common carp exhibit relatively stronger adaptive immune characteristics than juvenile fish. Gut microbiota analysis demonstrated significant stage-dependent differences in microbial diversity and community composition. Juvenile fish were enriched with bacterial taxa potentially associated with innate immune activation, whereas adult fish harbored distinct microbial communities linked to intestinal homeostasis and barrier maintenance. Furthermore, correlation analyses identified significant associations between specific microbial taxa and innate immune-related gene expression, suggesting a close association between gut microbiota composition and intestinal immune characteristics in juvenile and adult common carp. Collectively, these findings reveal stage-associated differences in intestinal immunity and gut microbial communities between juvenile and adult common carp, thereby providing insights into intestinal immune characteristics at different developmental stages in teleost fish.

Animals↗