Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Physiological responses”

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.

396 recordsLinked to original sources
PubMed2026

Integrated physiological and transcriptomic analyses reveal coordinated gill responses to heat stress in pikeperch (Sander lucioperca).

Climate change-driven warming of aquatic environments has made thermal stress an increasingly important factor influencing fish physiological homeostasis. Given their central roles in respiration and osmoregulation, gills are particularly responsive to variations in ambient temperature. Histological examination, physiological measurements, and transcriptome profiling were integrated to investigate the mechanisms associated with heat stress-induced gill injury in pikeperch (Sander lucioperca). Histological analysis revealed that exposure to 29 °C directly caused structural damage to the gills of pikeperch. Oxidative status was evaluated by measuring malondialdehyde (MDA) levels and the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). MDA accumulation was significantly enhanced under heat stress, while antioxidant enzyme activities (SOD, POD, and CAT) displayed a transient increase followed by a subsequent decline. Transcriptome profiling showed marked enrichment of the protein processing in endoplasmic reticulum pathway after heat stress, suggesting activation of endoplasmic reticulum (ER) stress in pikeperch gills. With increasing stress duration, the unfolded protein response (UPR) appeared unable to re-establish ER homeostasis, shifting ire1 and atf6 toward a pro-apoptotic state. Protein-protein interaction (PPI) analysis further highlighted hub genes potentially involved in heat stress-induced ER stress and apoptosis. TUNEL staining and western blotting collectively confirmed that heat stress triggered apoptosis in pikeperch gill tissue. Overall, this study provides new insights into the physiological and molecular responses of pikeperch gills to heat stress and enhances our understanding of thermal stress adaptation in cold-water aquaculture species under climate change.

Animals↗
PubMed2026

Contrasting redox-related physiological responses associated with HaGATA23 and HaGATA36 during Orobanche cumana parasitism in sunflower (Helianthus annuus L.).

Helianthus annuus is an economically important Asteraceae species used for seed oil production and ornamental purposes, but its production is seriously affected by the root-parasitic plant Orobanche cumana. GATA transcription factors are zinc-finger DNA-binding regulators involved in plant development and stress adaptation. However, the molecular characteristics of GATA transcription factors in Helianthus annuus and their contribution to Helianthus annuus -Orobanche cumana interaction remain poorly understood. Here, 36 HaGATA members were retrieved from the Helianthus annuus genome and classified into four phylogenetic clades. Chromosomal placement, collinearity, gene structure, motif composition, and promoter elements varied among the 36 HaGATA members, indicating evolutionary conservation coupled with functional diversification. Expression analysis and RT-qPCR analyses revealed differential expression patterns among HaGATA genes under O. cumana stress, with HaGATA23 markedly downregulated and HaGATA36 strongly upregulated. Overexpression of HaGATA23 was associated with increased malondialdehyde (MDA) accumulation and unfavorable changes in antioxidant enzyme activities, whereas its silencing showed the opposite physiological tendency. In contrast, overexpression of HaGATA36 reduced malondialdehyde accumulation, increased peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) activities, while its silencing showed the reverse tendency. These results indicate that HaGATA23 and HaGATA36 are candidate genes associated with contrasting redox-related physiological responses during O. cumana stress. This work provides evidence that GATA transcription factors are associated with redox-related physiological responses in sunflower under O. cumana treatment and identifies HaGATA23 and HaGATA36 as functionally divergent candidate genes for further validation.

Helianthus↗
PubMed2026

Physiological and molecular responses of coelomocytes to low- to mid-frequency acoustic exposure in the sea urchin Strongylocentrotus intermedius.

Underwater noise is a widespread environmental pollutant in marine ecosystems, yet the effects of low- to mid-frequency acoustic exposure on immune physiology and molecular responses in echinoderms remain unclear. In this study, the sea urchin Strongylocentrotus intermedius was exposed to continuous pure-tone acoustic stimulation at 80, 125, 250, 500, 750, and 1000 Hz for 3 h. Results showed that acoustic exposure significantly affected redox homeostasis, energy metabolism, and immune function in S. intermedius coelomocytes: the antioxidant system and glutathione redox balance were altered, as indicated by increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated reduced glutathione (GSH) content, and a higher GSH/GSSG ratio; glycolysis-related enzyme activities were enhanced, with increased pyruvate kinase (PK) activity under 125-500 Hz exposure and elevated hexokinase (HK) activity at 250 Hz; and immune function was impaired, as shown by increased coelomocyte mortality, reduced phagocytic activity, and inhibited acid phosphatase (ACP) and alkaline phosphatase (AKP) activities, whereas respiratory burst activity showed no significant change. Among all treatments, 250 Hz induced the most pronounced physiological responses. Transcriptomic analysis of coelomocytes from the 250 Hz group identified 663 differentially expressed genes, including 537 upregulated and 126 downregulated genes, mainly enriched in pathways related to apoptosis, phagosome, lysosome, glutathione metabolism, arachidonic acid metabolism, and carbohydrate metabolism. These findings indicate that low- to mid-frequency acoustic exposure can act as a physiological and molecular stressor to S. intermedius coelomocytes by affecting redox homeostasis, enhancing energy metabolism, and suppressing immune effector processes, with 250 Hz showing the strongest effect under the present exposure conditions. This study provides experimental evidence for evaluating the potential biological effects of low- to mid-frequency acoustic exposure on benthic echinoderms.

Animals↗
PubMed2026

Divergent responses of the gill, hepatopancreas, and eyestalk to acute alkalinity stress in Penaeus vannamei: Osmoregulatory compromise, metabolic trade-off, and endocrine disruption.

The expansion of aquaculture into inland saline-alkali waters is constrained by high carbonate alkalinity (CA), a severe environmental stressor for crustaceans. However, the systemic molecular mechanisms underlying its lethal toxicity remain poorly understood. In this study, we employed a comparative transcriptomic approach to investigate the tissue-specific responses of Pacific white shrimp, Penaeus vannamei, under acute lethal stress (48 h-LC50). We focused on three functionally distinct organs: the gill, hepatopancreas, and eyestalk. The results revealed a systemic but highly tissue-specific transcriptomic response. The gill, as the primary interface, exhibited severe structural impairment and critical failure of osmoregulation, highlighted by the significant downregulation of delta-1-pyrroline-5-carboxylate synthetase (P5CS). In contrast, the hepatopancreas initiates a profound metabolic trade-off, sacrificing growth-related pathways to bolster a robust antioxidant defense system, as evidenced by the activation of sulfur metabolism and high protein turnover. The eyestalk displayed a striking disconnect between hyperactivated stress signaling pathways (e.g., mTOR/FoxO) and the collapse of its protein secretory machinery, marked by the suppression of the ER translocon component Sec61. Collectively, our findings suggest that lethal alkalinity toxicity in P. vannamei results from systemic collapse driven by a complex interplay of osmoregulatory failure, metabolic trade-offs, and endocrine disruption. This study provides a comprehensive molecular snapshot of an organism at its physiological limit, offering novel insights into the adaptive strategies and ultimate tolerance boundaries of crustaceans in extreme environments.

Animals↗
PubMed2026

Transcriptomic insights into thermal stress reveal physiological trade-off between thermal stress adaptation and reproductive investment in Spodoptera litura.

Spodoptera litura, a highly polyphagous lepidopteran pest, poses a major threat to agricultural productivity due to its remarkable adaptability to diverse environmental conditions. Although heat stress is known to trigger transcriptional reprogramming in insects, the molecular mechanisms underlying thermal stress responses in S. litura remain poorly understood. In the present study, fourth-instar larvae were exposed to acute heat stress (44 °C) and compared with control conditions (27 ± 1 °C) to investigate heat-induced transcriptional alterations affecting physiology and reproduction. High-quality RNA-Seq data achieved more than 80% mapping efficiency, with a total of 15,782 transcripts were identified. Transcriptome analysis of S. litura larvae showed 323 differentially expressed genes (DEGs), of which 262 genes were significantly upregulated and 61 were downregulated in heat-stressed larvae compared to the control group. The DEGs were associated with stress response, reproduction, signalling, proteostasis, detoxification, oxidative stress, metabolism, development, and chromatin regulation. Heat shock proteins genes, including HSP70, HSP90, and HSP27, together with co-chaperones such as TRET-1, STIP1, and Starvin, were strongly upregulated, indicating enhanced cellular protection against protein damage and oxidative stress under heat stress. Conversely, key reproductive and cell cycle-related genes, including BARR, CAPD2, FEO, CDK2 and MORULA, were significantly downregulated, suggesting reproductive impairment and developmental arrest. RT-qPCR validation corroborated the RNA-Seq findings, demonstrating a heat-induced physiological trade-off that prioritizes survival over reproduction. Consistent with these molecular responses, heat-stressed insects exhibited marked reproductive impairment, including significant reductions in gonadosomatic index, eupyrene sperm bundle count, mating frequency, mating success, female calling behaviour, copulation duration, fecundity, and egg fertility. Collectively, these findings provide comprehensive insights into the molecular basis of thermal adaptation in S. litura and demonstrate that acute heat stress compromises reproductive fitness while activating conserved stress-response pathways that promote short-term survival.

Animals↗
PubMed2026

Uncovering molecular regulatory networks of low-temperature stress response in Trachinotus ovatus via integrated transcriptome and metabolome analyses.

Golden pompano (Trachinotus ovatus) is one of the most economically important marine fish species in China. It is susceptible to low-temperature stress, which significantly challenges its production and supply. Nevertheless, study on the regulatory mechanisms underlying low-temperature stress responses in golden pompano remains limited. Here, we firstly performed a time-series transcriptome analysis to reconstruct dynamic response patterns under low-temperature stress in golden pompano. Transcriptome profiling identified common differentially expressed genes (DEGs), including fos, hlf, and hmgb1, as well as condition-specific DEGs across distinct low-temperature stress groups. Based on cluster analysis, all DEGs were classified into five distinct expression patterns, reflecting diversified regulation of expression in golden pompano during low-temperature stress. Furthermore, condition-specific regulatory modules were explored via weighted gene co-expression network analysis (WGCNA), highlighting that the two module hub genes, serbf2 and lipc, might respond to low-temperature stress by regulating the lipid catabolic process. Subsequently, untargeted metabolomic analysis revealed that glycerophospholipid metabolism was a significantly enriched common pathway, highlighting its crucial role in mediating the response to low-temperature stress. Finally, by integrating transcriptomic and metabolomic analyses, a gene-metabolite interaction network associated with glycerophospholipid metabolism under low-temperature stress was established. These findings underscore the significance of multiple candidate genes and glycerophospholipid metabolism in golden pompano's response to low-temperature stress, thereby laying a solid molecular foundation for the development of low-temperature-tolerant fish strains.

Animals↗
PubMed2026

Phenotypic, physiological and transcriptomic analysis of graded salt stress responses in Pyrus betulifolia Bunge and functional characterization of the hub gene PbSTY46.

Pyrus betulifolia Bunge is a salt‑tolerant rootstock for pear, but its salt‑tolerance mechanisms remain largely unknown. In this study, P. betulifolia seedlings were subjected to graded NaCl stress at concentrations of 0 (CK), 50 (T1), 100 (T2), and 200 (T3) mM. We integrated phenotypic observation, physiological assessment, transcriptomic profiling, and functional gene validation to systematically elucidate its salt tolerance mechanisms. Salt stress inhibited seedling growth and root traits in a concentration-dependent manner, and T3 caused the most severe damage. Osmotic solutes responded differentially: soluble sugars peaked under T2, while proline peaked under T3. Antioxidant enzymes showed tissue-specific biphasic responses and declined after prolonged T3 stress. Meanwhile, chlorophyll and photosynthesis decreased, whereas anthocyanin increased, indicating a metabolic shift from photosynthesis to photoprotection. Transcriptome analysis revealed distinct responses depending on stress intensity: mild stress induced membrane lipid remodeling, moderate stress activated circadian rhythm and hormone signaling, and severe stress enhanced phenylpropanoid biosynthesis and thiamine metabolism. Gene Set Enrichment Analysis (GSEA) further highlighted progressive enrichment of phenylpropanoid biosynthesis, heme binding, and oxidoreductase activity. Weighted Gene Co‑expression Network Analysis (WGCNA) identified a blue module significantly positively correlated with root traits, from which the hub gene PbSTY46 was identified. Functional validation via overexpression, loss‑of‑function mutants, and pharmacological interventions (MeJA/DIECA) confirmed that PbSTY46 acts through JA signaling to enhance antioxidant enzyme activities and thereby confer salt tolerance. Collectively, P. betulifolia adopts a "survival‑first" strategy that coordinates growth arrest, osmotic homeostasis, and ROS scavenging. These findings establish PbSTY46 as a key regulator that links JA signaling to antioxidant defense. Thus, PbSTY46 represents a promising candidate for marker‑assisted breeding of salt‑tolerant pear cultivars.

Salt Stress↗
PubMed2026

Pre-transport dietary chitosan improves the physiological robustness of juvenile largemouth bass (Micropterus salmoides) by modulating antioxidant and inflammatory responses.

The acute stress caused by long-distance transport can lead to oxidative damage, immune dysfunction, and health deterioration in fish. This study evaluated dietary chitosan as a pre-transport nutritional strategy for juvenile largemouth bass (Micropterus salmoides). Five experimental diets contained chitosan at 0, 2.5, 5.0, 7.5, or 10.0 g/kg, designated as p0, p25, p50, p75, and p100, respectively, for 56 d. The effects of dietary chitosan were evaluated using growth performance, feed utilization, digestive function, antioxidant capacity, nonspecific immunity, and resistance to Aeromonas hydrophila infection. Then, fish from the p0 and p50 groups underwent a 12-h transport stress test, with samples collected before, during, and 7 d after transport. Dietary chitosan improved most of these parameters. Among the treatment groups, p50 and p75 showed the best overall performance. The dose-response analysis further indicated that the appropriate dietary inclusion range was 5.0-7.5 g/kg. Under transport stress, fish in the p50 group exhibited more stable antioxidant enzyme responses and lower lipid peroxidation, as indicated by reduced MDA levels. Consistent with these enzyme responses, antioxidant-related genes remained relatively stable. At the same time, expression patterns related to the Nrf2-Keap1 and NF-κB signaling pathways suggested that 5.0 g/kg chitosan alleviated transport-induced oxidative damage and inflammation. Dietary chitosan also attenuated pro-inflammatory gene induction and altered the temporal expression patterns of anti-inflammatory genes. Overall, 5.0-7.5 g/kg dietary chitosan is suitable for juvenile largemouth bass, and 5.0 g/kg may serve as an effective pre-transport dietary inclusion level.

Animals↗
PubMed2026

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↗
PubMed2026

Evolutionary expansion of the NF-Y gene family in bivalves and divergent subunit responses to thermal and pathogenic stress in the noble scallop.

Nuclear factor Y (NF-Y) is a conserved eukaryotic transcription factor complex that specifically interacts with the CCAAT motif. Prior research has demonstrated that this gene family participates in various biological processes, encompassing growth, development, and stress responses, across a broad spectrum of organisms. However, research on the role of the NF-Y family in bivalves remains limited. In this study, we comprehensively identified the NF-Y family in 34 bivalve species, and further investigated its expression in the noble scallop Chlamys nobilis. A total of 296 NF-Y genes were identified and classified into three subfamilies, NF-YA, NF-YB, and NF-YC. Phylogenetic analysis revealed that NF-YA and NF-YC have remained relatively conserved, whereas NF-YB has undergone significant expansion. Additionally, while substantial disparities in gene copy numbers exist across species, the motif composition and exon-intron structures within each subfamily demonstrate notable conservation. Tissue expression profiling revealed distinct expression patterns among CnNF-Y genes, with several members exhibiting relatively high transcript abundance in gonadal tissues. Furthermore, qRT-PCR results demonstrated that CnNF-YA2, CnNF-YB6, and CnNF-YC were significantly and continuously upregulated under heat stress. Conversely, several genes, particularly CnNF-YA2, CnNF-YB3, and CnNF-YB4, exhibited dynamic transcriptional responses to Vibrio parahaemolyticus exposure. These findings enhance our understanding of the evolutionary trajectory and functional diversification of the NF-Y gene family in bivalves, laying a theoretical foundation for future research on thermal adaptation, immune regulation, and molecular breeding in scallops.

Animals↗
PubMed2026

Proteomic responses of the oil palm pest Metisa plana (Psychidae) to farnesyl acetate exposure.

Metisa plana Walker (Lepidoptera: Psychidae) is a major defoliator of oil palm in Malaysia, causing substantial economic losses. Farnesyl acetate (FA), a sesquiterpenoid compound, has been proposed as a potential insecticidal agent against M. plana, yet its molecular impact on larval physiology remains poorly understood. Here, we employed label-free quantitative proteomics, functional enrichment analysis, and targeted transcript assessment to characterize the temporal proteomic response of M. plana larvae at 7 and 14 days after treatment (DAT) with FA. Principal component analysis revealed robust separation between treated and control samples at both time points, indicating sustained treatment-driven proteomic restructuring. Early exposure (7 DAT) elicited a heterogeneous response involving stress-associated proteins, redox enzymes, and cytoskeletal regulators, whereas later exposure (14 DAT) produced a consolidated profile characterized by metabolic reprogramming, downregulation of ribosomal proteins, induction of heat shock proteins, and enrichment of RNA surveillance and mitochondrial pathways. Targeted transcript analysis qualitatively supported proteomic trends for HSP83 and aldehyde dehydrogenase X, although limited amplification precluded quantitative inference. Collectively, these findings demonstrate that FA exposure drives a shift from acute proteomic perturbation toward a maintenance-oriented physiological state, prioritizing proteostasis, energy management, and stress adaptation over growth and development. This integrated molecular perspective provides mechanistic insight into the chronic effects of FA, highlighting its potential to suppress larval performance and informing the development of biorational, physiology-based pest management strategies in non-model insects.

Animals↗
PubMed2026

Systematic identification pepper CaE2F transcription factor reveals the role of CaDPb in drought stress response.

The EARLY 2 FACTOR (E2F) transcription factor (TF) family plays a pivotal role in regulating plant development and adaptations to environmental stresses. However, the physiological function of E2Fs in pepper (Capsicum annuum L.) are not well elucidated. In this work, we conduct a comprehensive genome-wide annotation of the E2F family within the Zunla-1 pepper genome and further explore the biological roles of CaDPb in response to drought stress. Through systematic bioinformatics analysis, we identify a total of nine CaE2F genes within the Zunla-1 genome, categorizing them into three distinct subgroups. Additionally, we discover multiple cis-regulatory elements in the CaE2F promoter regions associated with responses to plant hormones and drought stress. Public RNA-seq datasets reveal distinct expression profiles of CaE2F genes across various pepper tissues and their responses to environmental stimuli and plant hormones. Subsequently, the CaDPb gene is further functionally verified in drought response. Our findings indicate that TRV2:CaDPb silenced pepper plants are more sensitivity to drought. Furthermore, we show that CaDPb participates in the regulation of reactive oxygen species (ROS) production, the expression of drought-responsive genes, and the modulation of stomatal aperture. Taken together, our findings provide a comprehensive characterization of E2F genes in pepper and offer insights into the biological function of CaDPb in pepper drought stress response.

Capsicum↗
PubMed2026

Low-salinity stress alters growth, histology, physiology, and transcriptomic profiles of the gills and antennal glands in Macrobrachium rosenbergii.

Salinity is a major abiotic constraint in freshwater aquaculture of the giant freshwater prawn Macrobrachium rosenbergii, yet the coordinated roles of the gills and antennal glands, the two primary osmoregulatory organs in decapod crustaceans, under low-salinity stress remain poorly characterized. Here, we integrated histological, physiological, and transcriptomic analyses to characterize the adaptive responses of M. rosenbergii to acute (96 h) and chronic (8 weeks) exposure to salinity 5. Chronic low-salinity stress significantly impaired growth performance and decreased the survival rate. Acute stress induced thinning of the gill filaments, partial disorganization of pillar cells, and dilation of the intermicrovillar space in the antennal glands, whereas chronic stress caused gill vacuolization, cuticle thinning, and adaptive folding of antennal gland microvilli. In parallel, acute exposure significantly decreased hemolymph sodium and potassium ion concentrations but increased magnesium ion concentration, whereas chronic exposure increased hemolymph sodium and potassium ion concentrations, upregulated gill Na+/K+-ATPase activity, and enhanced hepatopancreatic antioxidant capacity. Transcriptomic analyses revealed distinct tissue-specific responses. Under acute stress, the gills preferentially activated pathways associated with cytoskeletal remodeling, motor proteins, and tight junctions, whereas chronic acclimation shifted the transcriptional response toward the renin-angiotensin system and glutathione metabolism. In the antennal glands, acute stress rapidly activated the renin secretion pathway, whereas chronic exposure promoted membrane remodeling by enriching pathways related to lipid and glycan metabolism. These findings reveal tissue-specific functional differentiation and synergistic coordination between the gills and antennal glands that underpin M. rosenbergii's adaptive response to low-salinity stress.

Animals↗
PubMed2026

Liver transcriptome analysis revealed multiple immune processes and lipid metabolism pathways involved in the defense response of the turbot (Scophthalmus maximus) against Aeromonas salmonicida.

Aeromonas salmonicida is a significant pathogen causing notable economic losses in Scophthalmus maximus aquaculture. This study utilized Illumina sequencing technology to examine the transcriptional response characteristics of S. maximus liver at 24 h following A. salmonicida infection. A total of 2363 differentially expressed genes (DEGs) were identified when compared to the negative control group. The immunity-related Toll-like receptor signaling pathway, NOD-like receptor signaling pathway, as well as metabolism-related PPAR signaling pathway and insulin signaling pathway, were notably enriched. Significant differences exist in the expression of key genes within the PPAR pathway, particularly cd36, acsl4a, pparαa, and plin2, all of which mediate the interaction between lipid metabolism and the immune response. These results offer valuable insights into the immunometabolic regulatory mechanism of S. maximus response to A. salmonicida infection.

Animals↗
PubMed2026

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↗
PubMed2026

Plasticity of hepatic metabolism in Arctic char (Salvelinus alpinus) in response to cyclic hypoxia.

The emergence of cyclic hypoxia puts aquatic organisms' homeostasis under significant strain. Energetic metabolism as well as protein synthesis and folding are particularly altered during hypoxia, while reoxygenation imposes an oxidative challenge. Currently, little is known about how hypoxia-sensitive organisms respond to large oxygen fluctuations. Our previous work on Arctic char revealed that this salmonid, despite being strongly affected by acute hypoxia and reoxygenation (H/R), can successfully reestablish homeostasis, notably through adjustments to hepatic mitochondrial metabolism. However, the mechanisms underlying this acclimation remain poorly understood. We hypothesized that Arctic char remodel their hepatic proteome to optimize energy metabolism, reorganize oxygen-demanding pathways, and maintain cellular homeostasis during repeated H/R cycles. By exposing Arctic char to two or fifteen days of diel cyclic hypoxia, we confirmed this species' limited capacity to respond to acute H/R. Nevertheless, after fifteen cycles, fish adjusted their energetic metabolism through coordinated regulation of carbohydrate and lipid pathways and upregulation of amino acid metabolism. Mitochondrial metabolism was strongly reorganized, particularly at the ubiquinone-Complex III interaction level, alongside adjustments in proline utilization and protein processing. Moreover, protein processing and folding pathways were stimulated in both mitochondria and the endoplasmic reticulum. However, chronic cyclic hypoxia may still promote non-mitochondrial ROS production, DNA replication stress, and impaired immune function. This study highlights how a hypoxia-sensitive fish progressively reorganizes its metabolism and oxygen-demanding pathways to establish a phenotype adapted to chronic cyclic hypoxia, while also revealing the physiological costs associated with this acclimation.

Animals↗
PubMed2026

Transcriptomic responses to developmental temperature in two field-collected Spodoptera exigua populations from Korea.

The beet armyworm, Spodoptera exigua, is a polyphagous insect whose development and seasonal occurrence are strongly influenced by temperature. However, transcriptomic responses to developmental thermal regimes remain insufficiently characterized in field-collected populations. In this study, we compared two Korean field-collected populations of S. exigua: a Haenam population collected in May and initially maintained at 15 ± 1 °C (HN), and a Jeju population collected in July and initially maintained at 27 ± 1 °C (JJ). F1 larvae from each population were reared under three fluctuating developmental temperature regimes: low (15-21 °C), middle (21-27 °C), and high (27-33 °C), followed by RNA-seq analysis. Differential expression analysis revealed population-associated variation in transcriptomic responses across developmental temperatures. HN exhibited a larger number of differentially expressed genes under the high-temperature regime, suggesting stronger transcriptomic sensitivity to elevated developmental temperature. Functional enrichment analyses identified population-associated differences in pathways related to heat response, oxidative metabolism, cytoskeletal organization, cuticle-associated processes, lipid metabolism, and immune-related functions. In JJ, heat-response and cuticle-related expression patterns were more prominent under warmer developmental conditions, whereas HN showed broader changes in stress- and metabolism-associated pathways under high temperature. Overall, this study provides a comparative transcriptomic analysis of two field-collected S. exigua populations under different developmental temperature regimes and identifies RNA-seq-based molecular response patterns associated with population-specific thermal response profiles.

Animals↗
PubMed2026

Distinct molecular responses to acute cold exposure revealed by comparative transcriptomic and metabolomic profiling in the bay scallop Argopecten irradians.

Acute cold stress can elicit distinct molecular responses even when bay scallop populations show similar phenotypic outcomes. We compared a seventh-generation fast-growing bay scallop line (BS) with a commercial control population (CC) during a 72-h acute cold exposure at -1 ± 0.3 °C. RNA-seq was used as the discovery layer, representative BS cold-responsive genes were evaluated by qRT-PCR, and paired LC-MS profiles provided a comparative metabolic layer. At baseline, 138 genes differed between BS and CC; after cold exposure, 134 of these baseline differences disappeared and 61 of 65 cold-state differences newly emerged. BS showed a larger transcriptomic response magnitude than CC, with 1129 cold-responsive genes compared with 28 genes in CC, and this ordering remained robust across multiple sensitivity analyses. Survival after 72 h was identical in BS and CC (83/90, 92.2% in each population). Biochemical responses were time-dependent and marker-specific: CAT, LZM, T-SOD and T-AOC showed population-by-time interactions, whereas GSH-Px and MDA did not, and the 72-h differences were not consistently favourable to BS. Metabolomic cold effects were strongly concordant between populations, and no feature showed a significant population-by-cold interaction. Features putatively assigned to arachidonic acid metabolism were enriched, but this provider-annotated pathway signal remains exploratory because authentic-standard confirmation was not performed. These findings indicate population-specific differences in molecular responsiveness but do not establish superior cold tolerance in BS.

Animals↗