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PubMed2026

Discovery and characterization of multifunctional bioactive peptides from Alaska Pollock (Gadus chalcogrammus) milt: hybrid in silico, in vitro, and proteomic approaches.

The growing demand for multifunctional bioactive peptides has sparked interest in underutilized marine by-products as sustainable bioresources. This study explored Alaska Pollock (Gadus chalcogrammus) milt protein as a novel source of peptides with anti-inflammatory, anti-hypertensive, and anti-diabetic effects. Protein composition was analyzed via LC-MS, followed by in silico digestion and bioactivity prediction. Molecular docking identified peptides targeting DPP-IV, α-glucosidase, ACE, GLP-1 receptor, COX-2, MuRF1, and the 20S proteasome. Among the candidates, a promising peptide (CLPPH) was synthesized and validated in vitro, demonstrating inhibitory effects on nitric oxide production, DPP-IV, ACE, and α-glucosidase. These results highlight CLPPH's potential as a multifunctional bioactive peptide and support the valorization of Alaska Pollock milt as a sustainable source for functional foods and nutraceutical applications.

Animals↗

PubMed2026

Simultaneously PYCR-1 and ALH-6 inhibition exacerbates 6-PPD quinone toxicity via disrupting proline and glutamate metabolisms and activating insulin signals in Caenorhabditis elegans.

Glutamate synthesized from the proline can serve as a precursor for key intermediate metabolites of citric acid cycle. Recently, we observed reduced glutamate content and expression of alh-6 controlling glutamate synthesis by 6-PPD quinone (6-PPDQ) in Caenorhabditis elegans. However, possible effect of 6-PPDQ on proline synthesis and the association with 6-PPDQ toxicity induction remain unclear. After 0.1-10 μg/L 6-PPDQ exposure, proline content was further reduced, and expression of pycr-1 governing proline biosynthesis was decreased. In 6-PPDQ exposed nematodes, RNA interference (RNAi) of pycr-1 decreased α-ketoglutarate content, enhanced mitochondrial dysfunction, reduced nicotinamide adenine dinucleotide (NADH) and reduced flavine adenine dinucleotide (FADH₂) contents, inhibited mitochondrial complex I/II activities, and decreased expressions of gas-1 and mev-1. Moreover, compared to single RNAi, double RNAi of pycr-1 and alh-6 exacerbated the 6-PPDQ toxicity in reducing α-ketoglutarate, NADH, and FADH₂ contents, and suppressing mitochondrial complex I/II activities and gas-1 and mev-1 expressions. Additionally, double RNAi of pycr-1 and alh-6 intensified toxicity of 6-PPDQ on longevity and caused upregulation of insulin ligand and receptor genes and downregulation of daf-16 and its targeted genes in 6-PPDQ exposed nematodes. Furthermore, after 6-PPDQ exposure, daf-16 RNAi suppressed pycr-1 and alh-6 expressions, suggesting formation of a regulatory feedback loop between pycr-1/alh-6 and daf-16. Our findings highlight involvement of disrupted proline and glutamate metabolisms in 6-PPDQ-induced mitochondrial dysfunction and reduced longevity.

Animals↗

PubMed2026

Molecular adaptation of caspase genes to salinity stress in the tropical sea cucumber Stichopus monotuberculatus: A comparative analysis across echinoderms.

Apoptosis is an essential physiological process that plays a critical role in development and tissue homeostasis. Caspases, as central regulators of apoptosis, are crucial in controlling inflammation and cell death. In this study, we investigated the caspase gene family in Stichopus monotuberculatus to explore their potential roles in salinity stress adaptation. Five caspase genes were identified from the genome of S. monotuberculatus, including Smcaspase3, Smcaspase6, Smcaspase8a, Smcaspase8b, and Smcaspase8c. Phylogenetic analysis revealed that these Smcaspase genes clustered into distinct caspase subfamilies and showed high conservation with homologs from other echinoderms and representative vertebrates. Conserved motif and gene structure analyses showed relatively similar structural patterns within each clade, whereas divergence was observed among different subfamilies. Promoter analysis identified numerous cis-acting elements related to gene regulation, immune response, and growth and development. Expression profiling under salinity stress showed that Smcaspase8a was significantly upregulated, particularly under prolonged stress, whereas the other genes exhibited limited transcriptional responses. Our findings highlight caspase function in salinity stress and provide the foundation of molecular salinity adaptation mechanisms in S. monotuberculatus.

Animals↗

PubMed2026

Molecular characterization of 16 MAPK genes in silver carp (Hypophthalmichthys molitrix) and the differences of their mRNA expression between Qiandao Lake and Taihu Lake.

Mitogen-activated protein kinase (MAPK), a serine-threonine protein kinase, is involved in a variety of stress-induced responses and also plays an important regulatory role in cell metabolism. In the study the open reading frames (ORFs) of 16 MAPK genes in silver carp (Hypophthalmichthys molitrix) were obtained and verified, with the evaluations of their taxonomy, structures, conserved motifs, and evolutionary linkages. And the expression patterns of these genes in the silver carp from Qiandao Lake and Taihu Lake were explored for better understanding the response of MAPK genes to different water environment. MAPK genes of silver carp were divided into three subfamilies, including extracellular signal-regulated kinase (ERK) subfamily, p38 subfamily and C-Jun N-terminal kinase (JNK) subfamily. All these genes possessed similar structures and conserved motifs of MAPK family. Realtime qPCR revealed that the expression patterns of 10 MAPK genes (ScMAPK1, ScMAPK3, ScMAPK4, ScMAPK7, ScMAPK15, ScMAPK8a, ScMAPK8b, ScMAPK9, ScMAPK10 and ScMAPK11) in head kidney, spleen and gill of silver carp in Taihu Lake and Qiandao Lake were different. These findings provide a basis for further research on the function of MAPK in silver carp.

Animals↗

PubMed2026

Identification of aquaporin (AQP) genes in the noble scallop Chlamys nobilis and characterization of their expression under low-temperature stress.

Aquaporins (AQPs) are transmembrane channel proteins essential for water homeostasis and cellular stress responses. In marine bivalves, their roles in cold tolerance remain poorly understood despite frequent winter mortality events in aquaculture. Here, we identified nine AQP genes in the genome of the economically important noble scallop Chlamys nobilis. Phylogenetic analysis revealed strong conservation with other bivalve AQPs, and structural features, including conserved NPA motifs and ar/R selectivity filters, support their canonical water/glycerol transport functions. Tissue-specific expression profiling showed predominant enrichment in osmoregulatory tissues (gills, intestine) and gonads. Under both chronic and acute low-temperature stress from 23 °C to 9 °C, most CnAQP genes exhibited transient upregulation followed by suppression. Notably, CnAQP4 displayed sustained upregulation, implicating it as a key mediator of long-term cold adaptation. Promoter analysis further revealed abundant cis-elements linked to growth and development as well as immune regulation. Our findings provide the first comprehensive characterization of the AQP family in C. nobilis, highlighting its critical role in maintaining cellular integrity during cold stress and offering molecular targets for selective breeding of cold-tolerant scallop strains.

Animals↗

PubMed2026

Transcriptomic and RNAi analyses reveal chloride channel 3-associated osmoregulation in Litopenaeus vannamei under low-salinity stress.

Chloride channels and transporters are important for cellular volume regulation and salinity adaptation in euryhaline crustaceans, yet the intestinal transcriptional relationship between plasma-membrane and intracellular chloride pathways remains unclear in Litopenaeus vannamei. In this study, RNA interference of anoctamin 1 (ANO1) was combined with intestinal transcriptome sequencing under the production-relevant low-salinity condition of salinity 3. ANO1 silencing produced a focused transcriptional response, with 16 differentially expressed genes (DEGs) identified (11 upregulated and 5 downregulated). Functional enrichment indicated that these genes were associated with transporter activity, cytoskeletal organization, extracellular matrix-receptor interaction, membrane lipid metabolism, and vesicular processes. Notably, a transcript encoding chloride channel protein 3 (CLC-3) was significantly upregulated following ANO1 knockdown, suggesting a potential transcriptional relationship between ANO1 and CLC-3 in chloride homeostasis. Based on this finding, CLC-3 was selected for full-length cDNA cloning, sequence characterization, salinity-gradient expression analysis, and RNAi-based functional assessment. The cloned CLC-3 cDNA was 2883 bp in length and encoded an 850 amino acid protein containing a conserved voltage-gated chloride channel (Voltage-CLC) domain and two cystathionine β-synthase domains. Phylogenetic analysis placed LvCLC-3 within the intracellular CLC-c clade, and tissue distribution analysis showed the highest CLC-3 expression in the intestine. Intestinal CLC-3 expression responded nonlinearly to salinity variation, peaking at salinity 20. Under salinity 3, CLC-3 knockdown reduced ANO1, Na+/K+-ATPase alpha subunit, and Na+-K+-2Cl- cotransporter transcript levels, whereas glutamate-gated chloride channel expression increased. Mild hepatopancreatic structural alterations were also observed after CLC-3 knockdown. These findings suggest that CLC-3 is a salinity-responsive intracellular chloride-transporter candidate associated with intestinal ion-transport-related transcriptional responses after ANO1 suppression in L. vannamei, although the underlying physiological mechanism requires further validation.

Animals↗

PubMed2026

Comparative genomic and proteomic analysis reveals orthogroup structured evolution of tick protease inhibitors.

Protease inhibitors (PIs) play central roles in regulating endogenous proteolysis and host-parasite interactions in ticks. However, the evolutionary architecture underlying their diversification across tick lineages remains insufficiently resolved. Here, we performed a genome-wide comparative analysis of predicted proteomes from 14 tick species to systematically characterize PI repertoires. In total, 4931 putative PIs were identified and grouped into 20 families using the MEROPS classification system. Further, PI families such as Antistasin, WAP-type, and Pacifastin, which have not previously been systematically reported in tick genomes, were classified. Orthogroup inference demonstrated that PI expansion is structured at the level of evolutionary lineages rather than uniformly across families. By stratifying orthogroups according to duplication burden and taxonomic conservation, we identified a broadly conserved single-copy core under strong purifying selection. Motif level analysis of serpin reactive center loops further revealed conservation of inhibitory specificity within single copy orthogroups and diversification of key functional residues in duplication-associated lineages. Integration of secretion prediction and tissue-resolved proteomics from Hyalomma anatolicum and Rhipicephalus microplus demonstrated that evolutionary stratification is reflected at the protein level. Together, these findings provide an orthogroup-resolved evolutionary framework linking duplication dynamics, molecular evolution, and tissue-level protein deployment. This integrative approach offers a systematic basis for prioritizing conserved and diversified PI lineages for future functional and anti-tick intervention studies.

Animals↗

PubMed2026

Structural and tissue-specific organisation of endocrine Fgf19 and Fgf21 signalling in rainbow trout.

Endocrine fibroblast growth factors (FGF19 subfamily) play a key role in regulating metabolic homeostasis in vertebrates. However, their functional diversification in salmonids remains poorly understood. In this study, we conducted an integrative characterisation of Fgf19 and Fgf21 signalling in rainbow trout (Oncorhynchus mykiss) by combining phylogenetic, structural and expression analyses. Phylogenetic analyses revealed the conservation of single fgf19 and fgf21 genes, despite the extensive expansion of receptors post-Ss4R (salmonid-specific fourth-round whole genome duplication). Structural modelling and molecular dynamics simulations demonstrated the stable interactions of both ligands to multiple Fgfr isoforms, with receptor-specific energetic profiles and conserved core interaction residues. Tissue expression profiling revealed clear differences from mammalian models, such as predominant hepatic fgf19 expression and the absence of hepatic fgf21 under basal conditions. In addition, there were complex and tissue-dependent distributions of fgfr and klotho transcripts. These findings support a receptor-driven diversification model of endocrine Fgf signalling in salmonids, suggesting enhanced endocrine plasticity associated with the retention of receptors following post-genomic duplication. Taken together, our findings provide new insights into the structural and regulatory organisation of endocrine Fgf signalling, as well as its potential role in metabolic regulation in rainbow trout.

Animals↗

PubMed2026

Genomic identification and functional characterization of the nuclear receptor gene family in relation to sex determination and gonad development in the Pacific oyster (Crassostrea gigas).

Nuclear receptors (NRs) are a large superfamily of transcription factors that control a wide range of physiological processes by modulating the expression of downstream target genes. Numerous studies have confirmed that NR family members play critical and conserved roles in sex determination and gonadal development across metazoans. However, in mollusks, systematic characterization of NRs and their potential functions in gonadal regulation remain largely unexplored. In this study, 46 NR gene family members in the Pacific oyster (Crassostrea gigas) were identified and assigned to eight subfamilies. All NR family members contain at least one of the two core domains (DNA-binding domain, DBD; ligand-binding domain, LBD), and conserved exon-intron structures were observed within the same subgroup, indicating their evolutionary conservation. Furthermore, expression profiling revealed high expression of CgNR2F, CgNR5A1-1, and CgNR0B1 in undifferentiated gonads, suggesting their potential involvement in sex determination. CgNR1A and CgNR2E5 were specifically expressed in female gonads and exhibited female-biased expression patterns, indicating a putative role in ovarian development. Moreover, CgNR3A and CgNR3B showed high expression levels during the undifferentiated stage and early male development stage, implying their possible participation in male gonadal development and gametogenesis. These results expand the understanding of the NR gene family in C. gigas and help elucidate the potential functions of NR genes in sex determination and gonadal development.

Animals↗

PubMed2026

A conserved distal-tail helical extension defines a tailspike attachment architecture in Gram-negative siphophages.

Rapid growth of bacteriophage genome collections has outpaced functional annotation of tail-tip proteins, limiting comparative analysis of host-recognition structures. Starting from a shared distal-tail gene organization in the Salmonella phages 9NA and Jersey, I developed a morphogenetic bioinformatic framework integrating gene synteny, sequence comparison, profile hidden Markov model (HMM) screening, structural evidence, structure-aware searching, and AlphaFold modeling. Comparison with the experimentally characterized lambda and Sf11 tail assemblies identified a predominantly alpha-helical C-terminal extension of the distal-tail (DT) protein associated with tailspike attachment, termed the distal-tail helical extension (DT-helix). Screening 541,986 proteins from 5167 complete NCBI RefSeq tailed-phage genomes, followed by evidence-based evaluation of sequence, genomic context, and structural architecture, identified 165 curated DT-helical-extension-associated phages. Their DT proteins segregated into six sequence groups. In the four principal multi-member groups, cognate tailspikes showed group-specific conservation in proximal N-terminal regions but substantially greater downstream diversity, consistent with sequence constraint at the DT-tailspike attachment boundary. A complementary ProstT5/Foldseek search supported the established groups but revealed no convincing additional highly divergent family. Together with the experimentally characterized Sf11 attachment interface, these findings define a recurrent morphogenetic architecture linking conserved distal-tail scaffolds to more variable receptor-binding proteins across siphophages infecting Gram-negative bacteria. Although universal exchangeability is not established, the identified scaffold-receptor-binding boundaries provide a framework for molecular characterization and rational phage engineering. Accession-level information for the 165 curated phages is available through PhageTailDB.

Viral Tail Proteins↗

PubMed2026

Characteristics and functions of a cell adhesion molecule PvCadN in Penaeus vannamei during WSSV infection.

Cell adhesion not only maintains the integrity of the organism, but also plays an important role in the immune system, which is involved in modulation in the interaction between host and virus. In this study, a novel cell adhesion molecule from Penaeus vannamei, designated as PvCadN, was investigated. It had the typical molecular characteristics of cadherin family, with multiple extracellular cadherin repeat domains, a transmembrane region, and a conserved β-catenin-binding motif. Pvcadn is expressed ubiquitously across all detected tissues, with the highest transcriptional level in gills. RNA interference-mediated silencing of pvcadn significantly impaired the adhesion ability of shrimp hemocytes. Upon WSSV infection, pvcadn showed a tissue-specific expression pattern, with upregulation in gills and downregulation in hemocytes. Knockdown of pvcadn markedly suppressed the transcription of WSSV immediate-early gene ie1 and replication of the viral genome in vivo, suggesting that PvCadN acted as a potential virus-associated molecule. Furthermore, it was found that PvCadN was regulated by Lvβ-catenin, a core molecule in the Wnt signaling pathway that functions in innate immunity, at the transcriptional and protein levels. Silencing of lvβ-catenin significantly downregulated pvcadn transcription, and Lvβ-catenin bound directly to the Cadherin C domain of PvCadN. In summary, the study revealed that PvCadN was a key cell adhesion molecule involved in WSSV infection, which was regulated by Lvβ-catenin. Our findings will provide fundamental data for further investigation into cadherin-mediated immune regulation in shrimp, and offer new insights for the prevention and control of WSSV.

Animals↗

PubMed2026

The genomic origins and evolutionary path to a key innovation in the world's most venomous snakes.

Evolutionary innovation is a catalyst for the colonization of new environments and the adaptive radiations of major groups. Novel traits typically evolve through the modification of preexisting characters, but the genetic paths underlying their origin have been challenging to trace, and the general requirements for and relative order of different kinds of gene mutations have been difficult to assess. Here, we trace the genomic origins of four procoagulant venom toxins (factor X, factor V, group I phospholipase A2, and Kunitz-type toxins) that collectively underlie a novel, especially potent blood-clotting venom type in the recently evolved Australian brown snake and taipan clade. We find evidence for a previously unknown fifth toxin, coagulation factor VII, and show that the toxins evolved through two distinct genetic paths. The factor X and factor V toxins evolved through the sequential de novo co-option of ancestral clotting factor proteins that entailed their heterotopic expression in the venom gland, the fixation of segmental duplications containing each locus, and subsequent gain-of-function mutations that rendered factor X and factor V constitutively active. In contrast, the phospholipase A2 and Kunitz-type toxins evolved by modifying the functions of neurotoxins that were part of the venom arsenal. Our findings support models in which innovative mutations in single-copy genes precede gene duplication in the evolution of novel proteins and offer a rare view into the genesis of a complex trait that has played a central role in a major adaptive radiation.

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

Metabolomic Responses to Oral Glucose Tolerance Test and Hyperinsulinemic-euglycemic Clamp in CKD.

BACKGROUND: The oral glucose tolerance test (OGTT) captures integrated physiological responses involving intestinal glucose absorption, incretin signaling, and endogenous insulin secretion, whereas the hyperinsulinemic-euglycemic clamp (clamp) isolates insulin-mediated glucose uptake. Comparing plasma metabolomic responses to these two challenges may identify processes specific to intestinal nutrient delivery and how they vary in CKD. METHODS: Targeted plasma metabolomics was performed in 59 adults without diabetes (39 with CKD [eGFR <60 mL/min/1.73 m2] and 20 controls) from the Study of Glucose and Insulin in Renal Disease (SUGAR). Each participant underwent a 75-g OGTT and clamp approximately one week apart. Eighty-eight plasma metabolites were quantified at fasting and during each challenge. Metabolite levels were log-transformed and normalized using Systematic Error Removal Using Random Forest (SERRF). Metabolites were classified using adjusted regression slopes relating OGTT and clamp responses. RESULTS: The mean (SD) age and eGFR were 64 (13) years and 54 (26) mL/min/1.73 m2, respectively, and 41% were female. In the overall cohort, OGTT and clamp induced broad plasma metabolic changes, with 63 (72%) and 76 (86%) metabolites significantly altered from fasting, respectively. Seventy-three metabolites (83%) demonstrated a significant relationship between OGTT and clamp responses. Of these, 22 (25%) exhibited true concordance and 51 (58%) demonstrated similar directional changes but differed in magnitude. A total of 15 (17%) metabolites were discordant or non-corresponding, of which only three were discordant. The non-corresponding metabolites were enriched in amino acid metabolism. Eleven metabolites (13%) demonstrated differential responses between OGTT and clamp by CKD status, involving amino acid and glucose metabolism pathways. CONCLUSIONS: Metabolomic responses to OGTT and clamp were largely directionally concordant but differed in magnitude, with attenuation during OGTT. Discordant metabolites were rare, while non-corresponding metabolites were confined to amino acid pathways. CKD modified OGTT-clamp correspondence for metabolites involved in amino acid and glycolytic metabolism.

Journal Article↗

PubMed2026

Chalcone-indole hybrid scaffolds as promising anticancer drug candidates: a mini-review.

Cancer treatment is hampered by severe systemic side effects, poor tumor selectivity, and multidrug resistance (MDR). Molecular hybridization integrates chalcone and indole, two privileged antitumor pharmacophores, into one scaffold to generate chalcone-indole hybrids that synergistically enhance antitumor potency, improve tumor targeting, and reverse MDR. This mini-review analyzes literature from 2020 to 2026 on chalcone-indole anticancer hybrids. Based on structural modification patterns, the reported hybrids are categorized into four subgroups: simple substituted, α/β-position modified, N-1 fatty acid-substituted, and multi-pharmacophore fused hybrids. For each category, we summarize structure-activity relationships (SARs), antiproliferative activity, selective toxicity, molecular mechanisms, and in vivo xenograft performance. Most lead compounds exert tumor-suppressive effects via tubulin polymerization inhibition, G2/M cell cycle arrest, ROS overaccumulation, and mitochondrial-dependent apoptosis. Representative hybrids 10a, 12a, 21a, and 25a exhibit remarkable efficacy against drug-resistant colorectal, lung, and breast tumors with favorable in vivo safety. We highlight the application potential of different subtypes for specific malignancies, including α/β-modified analogues for resistant colorectal cancer, N-1 fatty acid-platinum conjugates for platinum-resistant lung cancer, NLRP3 inhibitor 7a for oral cancer, and multi-pharmacophore fused derivatives for broad-spectrum activity. Current bottlenecks limiting clinical transformation are discussed. This review provides structural design rules for developing novel chalcone-indole targeted anticancer agents.

Humans↗

PubMed2026

Functions of tandem-repeat galectins and domain coordination governs galectin-4 activity in grass carp (Ctenopharyngodon idella).

Galectins are β-galactoside-binding lectins that play essential roles in innate immunity. Among them, tandem-repeat galectins (TrGals), typically composed of two distinct carbohydrate-recognition domains (CRDs) connected by a linker peptide, are well established as key regulators of pathogen recognition and host defense in mammals. However, their structural diversity and immunological functions in teleost fish remain poorly understood. In this study, five TrGals (Gal-4, Gal-8a, Gal-8b, Gal-9, and Gal-9like) were identified in grass carp. Sequence and structural analysis revealed that Gal-8a/b, Gal-9, and Gal-9like possess the canonical two-CRD architecture, whereas Gal-4 uniquely contains four highly similar tandem-repeat domains. All five TrGals were broadly expressed across examined tissues, with predominant expression in the liver. Upon Aeromonas hydrophila infection, Gal-4, Gal-8a, Gal-8b, and Gal-9 were rapidly up-regulated at early time points (3-6 h). To elucidate the functional significance of CRD number, recombinant full-length CiGal-4 (CiGal4-full) and three truncated variants containing one, two, or three CRDs (CiGal4-1CRD, CiGal4-2CRD, and CiGal4-3CRD) were generated and systematically characterized. All recombinant proteins contained the conserved β-sheet structure typical of galectin CRDs. Functional assays revealed that CiGal4-full displayed the strongest growth-inhibitory activity against all tested bacteria, whereas CiGal4-1CRD showed the weakest effect. Notably, CiGal4-2CRD exhibited the most potent bactericidal activity, surpassing the full-length protein, while CiGal4-3CRD showed no further enhancement. CiGal4-full and CiGal4-2CRD showed superior carbohydrate-binding activities compared with the other variants. Collectively, these results reveal that CRD copy number alone does not linearly determine galectin function. Instead, domain organization and conformational coordination are critical for optimizing antimicrobial activity. This study provides new insights into the structure-function relationships and evolutionary diversification of galectins in teleosts and highlights their potential as novel antimicrobial and immunomodulatory agents in aquaculture.

Animals↗

PubMed2026

Integrated transcriptomic and metabolomic analyses provide new insights into the response of black rockfish (Sebastes schlegelii) larvae to temperature fluctuations.

Sebastes schlegelii usually encounter elevated and fluctuating water temperatures near its upper thermal limit in summer, yet the hepatic responses of larvae to repeated temperature fluctuation regimes remain unclear. To address this question, S. schlegelii larvae were exposed for 8 days to four thermal regimes: constant 18 °C (CT), constant 28 °C (HT), intermittent cooling from 18 to 8 °C followed by recovery to 18 °C (FL), and intermittent warming from 18 to 28 °C followed by recovery to 18 °C (FH). Survival rate was evaluated, and integrated liver transcriptomic and metabolomic analyses were performed. Final survival rates were 96.67% in the CT group, 97.78% in the FL group, and 77.78% in the FH group. Survival rate in the HT group (38.89%) was significantly lower than that in the other three groups (P < 0.05). HTvsCT, FLvsCT, FHvsCT, and FHvsHT comparisons identified 2598, 1207, 622, and 2404 differentially expressed genes and 627, 606, 690, and 610 differential metabolites, respectively. KEGG enrichment analyses of DEGs and SDMs in HTvsCT highlighted HSP-mediated proteostasis, endoplasmic-reticulum protein processing, branched-chain and sulfur amino acid metabolism, glutathione metabolism, and central carbon metabolism, with upregulated hsp90aa1, bckdha, gclc, and pfkp and reduced levels of branched-chain amino acids and methionine. Compared with HT, FH showed attenuated disturbances in proteostasis, amino acid and redox regulation, and central carbon metabolism, together with recovery-associated glycerophospholipid turnover. FL primarily induced polyunsaturated fatty acid (PUFA)-related membrane lipid remodeling. These findings indicate that hepatic responses differed between continuous high-temperature exposure and temperature fluctuations and between fluctuation regimes.

Animals↗

PubMed2026

Systematic review of the mutations in the active antigenic site Ø of the prefusion F protein of the Respiratory Syncytial Virus (RSV) following the implementation of monoclonal antibody prophylaxis.

BACKGROUND: Monoclonal antibody (mAb) nirsevimab, which targets the antigenic site Ø of the prefusion F protein (pre-F) of RSV, was introduced for RSV prophylaxis in several countries. METHODS: A systematic search was conducted between January 1, 2022, and July 31, 2026 for studies analyzing substitutions within the epitope of pre-F RSV protein, which is the target of nirsevimab, after the implementation of the mAb. We searched across PubMed, Scopus, Web of Science and ClinicalTrial.gov for studies involving children with confirmed RSV infection, that conducted genomic analysis. RESULTS: Seven studies (five observational and two randomized controlled trials) including 2156 RSV-positive samples (RSV-A: 1347, RSV-B: 809) were analyzed. RSV-A strains showed limited variability within antigenic site Ø, with K65R being the most common substitution and K209E being the only intermediate-resistance RSV-A substitution. RSV-B strains demonstrated substantially higher substitution frequencies, particularly involving I206M, Q209R, and S211N. Most identified substitutions appeared to represent naturally occurring polymorphisms and retained susceptibility to nirsevimab, while multiple RSV-B substitutions and combinations involving residues 64-68 and 204-208 demonstrated reduced susceptibility or high-level resistance. Resistance-associated variants were detected in 28 of 2156 (1.3%) RSV-positive samples and exclusively among nirsevimab breakthrough infections. In a sub-analysis restricted to nirsevimab-treated individuals, resistance-associated variants were significantly more frequent among RSV-B than RSV-A (9.8% vs 0.5%; p < 0.001). CONCLUSION: Most substitutions that were detected within the nirsevimab antigenic site reflect ongoing natural RSV evolution and do not significantly affect nirsevimab susceptibility. However, detection of resistance-associated variants highlights the importance of continuous genomic and phenotypic surveillance.

Humans↗