Search Results (617)

Enhancing photosynthetic efficiency represents a key approach for improving crop biomass, with its translation into higher grain yield being contingent upon the efficiency of photosynthate partitioning toward harvestable organs. The Rubisco small subunit (RbcS) gene family plays an essential role in this process by stabilizing and regulating Rubisco assembly and activity during photosynthesis. In this study, we identified 61 RbcS genes across B. napus, B. juncea, and B. carinata, and their diploid progenitors B. rapa, B. nigra, and B. oleracea by genome-wide screening and bioinformatic approaches. Phylogenetic relationships, gene structures, conserved domains, collinearity, cis-regulatory elements, expression profiles, and haplotype variations were systematically investigated, revealing the potential functional role significance and regulatory complexity of RbcS genes in photosynthesis. The results imply that the promoter type of this gene family may belong to light-inducible promoters. Furthermore, while a haplotype analysis provided valuable insights for selecting germplasm with potentially high photosynthetic efficiency, definitive confirmation of their effects requires functional validation. Collectively, our results establish a theoretical foundation for understanding the molecular mechanisms of BnRbcS genes and propose candidate genetic targets for further exploration to enhance photosynthetic performance in rapeseed breeding. Full article

CSN2, a highly conserved subunit of the COP9 signalosome (CSN), serves as the primary binding site for Cullin in the CSN complex. This interaction, dependent on lysine residues, positions CSN2 as a key player in approximately 20% of CRL-mediated ubiquitination reactions, a critical regulatory pathway for growth, development, and cellular processes in eukaryotes. While the role of CSN2 in human cells has been partially characterized, its function in rice (OsCSN2) remains poorly understood. Building on our previous findings regarding OsCSN2 function under natural light, this study investigates its regulatory mechanisms in rice seedlings under red and far-red light conditions. We demonstrate that under natural light, OsCSN2 mainly affects rice GA homeostasis by regulating the expression of SLR1 and influences rice photomorphogenesis by regulating the expression of the COP1-HY5 complex, thereby controlling rice growth through two pathways. Unlike under natural light, under red light, OsCSN2 promotes the expression of OsGID1, enhances the interaction between OsGID1 and OsSLR1, and promotes GA accumulation and OsPIL14 expression, leading to rice stem growth and inhibition of coleoptile elongation. Under far-red light, OsCSN2 mainly promotes the expression of OsCOP1, increasing the formation of the COP1-HY5 complex, which inhibits photomorphogenesis and coleoptile elongation. Lysine site mutations in OsCSN2 affect the interaction between the OsCSN complex and CRLs, regulating CRL-mediated ubiquitination reactions, promoting the ubiquitin-mediated degradation of OsSLR1 and OsCOP1, and thus promoting rice growth. These findings not only elucidate the functional roles of OsCSN2 in rice growth regulation but also provide valuable genetic resources for breeding rice varieties with enhanced agronomic traits. Full article

Evidence increasingly indicates that synaptic vesicle dysfunction emerges early in Parkinson’s disease (PD), preceding overt dopaminergic neuron loss rather than arising solely as a downstream consequence of neurodegeneration. α-Synuclein (αSyn), a presynaptic protein that regulates vesicle clustering, trafficking, and neurotransmitter release under physiological conditions, exhibits dose-, conformation-, and context-dependent actions that distinguish its normal regulatory roles from pathological effects observed in disease models. This narrative review synthesizes findings from a structured search of PubMed and Scopus, with emphasis on α-syn-knockout (αSynKO) and BAC transgenic (αSynBAC) mouse models, which do not recapitulate the full human PD trajectory but provide complementary insights into αSyn physiological function and dosage-sensitive vulnerability. Priority was given to studies integrating ultrastructural approaches—such as cryo-electron tomography, high-pressure freezing/freeze-substitution TEM, and super-resolution microscopy—with proteomic and lipidomic analyses. Across these methodologies, several convergent presynaptic alterations are consistently observed. In vivo and ex vivo studies associate αSyn perturbation with impaired vesicle acidification, consistent with altered expression or composition of vacuolar-type H⁺-ATPase subunits. Lipidomic analyses reveal age- and genotype-dependent remodeling of vesicle membrane lipids, particularly curvature- and charge-sensitive phospholipids, which may destabilize αSyn–membrane interactions. Complementary biochemical and cell-based studies support disruption of SNARE complex assembly and nanoscale release-site organization, while ultrastructural analyses demonstrate reduced vesicle docking, altered active zone geometry, and vesicle pool disorganization, collectively indicating compromised presynaptic efficiency. These findings support a synapse-centered framework in which presynaptic dysfunction represents an early and mechanistically relevant feature of PD. Rather than advocating αSyn elimination, emerging therapeutic concepts emphasize preservation of physiological vesicle function—through modulation of vesicle acidification, SNARE interactions, or membrane lipid homeostasis. Although such strategies remain exploratory, they identify the presynaptic terminal as a potential window for early intervention aimed at maintaining synaptic resilience and delaying functional decline in PD. Full article

The respiratory mucosal system plays a critical role in the pathogenesis of allergic asthma (AA). Currently, therapeutic Fc fusion proteins are as a promising strategy for mucosal vaccine delivery systems. In this work, a plasmid encoding the Mycobacterium tuberculosis ESAT6-Fc fusion protein was successfully constructed, and high-purity ESAT6-Fc fusion protein was subsequently obtained. Administered via intranasal immunization in OVA-induced allergic asthma model mice, ESAT6-Fc fusion protein significantly alleviated airway inflammation and mucus production, and reduced the proportions of Th2 cells, Th17 cells, and eosinophils, while increasing the proportions of Th1 cells with no histopathological changes to major organs. To elucidate the underlying immune regulatory mechanisms of ESAT6, integrated transcriptomic and proteomic analyses were performed, revealing Th1/Th2 cell differentiation and Th17 cell differentiation as the two most significantly enriched pathways at both the gene and protein levels. CD3e (CD3E) and CD3g (CD3G), two essential subunits of the TCR–CD3 complex, were identified as core target factors. The validations from the ESAT6-Fc-treated AA lung tissues, as well as co-cultured TH0 cells from C57BL/6J mice and CD2.4 dendritic cells exposed to the ESAT6-Fc protein, were consistent with the aforementioned findings. ESAT6-Fc exhibits a safe profile with favorable efficacy against OVA-induced AA via intranasal immunization, and ESAT6 ameliorates AA by regulating the differentiation of Th0 cells into Th1 cells, which were closely associated with the down-regulation of CD3e and CD3g expression, presumably leading to the impairment of TCR–CD3 complex assembly. ESAT6-Fc fusion protein demonstrates promise as a potential safe intranasal immunotherapy agent for the treatment of AA. Full article

Background: Pneumonia contributes to post-burn morbidity and mortality. Understanding the mechanisms that predispose burn patients to pneumonia is crucial to both stratifying patients at increased risk and developing targeted interventions. Methods: A prospective observational study was conducted with 47 human patients who sustained large burn injuries with serum collected on days 2 and 3 post-burn and assessed for Angiopoietin-1 (Ang-1) and -2 (Ang-2). C57BL/6 mice were subjected to either sham injury or a 12.5% total body surface area (TBSA) scald burn injury, and plasma and lungs were assessed. Results: Patients who developed pneumonia within 30 days of injury had higher serum Ang-2 and Ang-2/1 ratio on post-injury days 2 and 3. Similar to patient findings, we observed an increase in Ang-2 in burn mice compared to sham. Within the lungs of burn mice, we found significant increases in Tyrosine kinase with immunoglobulin and epidermal growth factor homology domains 2 (TIE2) receptor transcript Tek, downstream mediators TNFAIP3 Interacting Protein 2 (Tnip2) and phosphoinositide-3-kinase regulatory subunit 1 (Pik3r1), in addition to endothelial adhesion molecules intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), along with neutrophil infiltration and markers compared to sham. Conclusions: These findings suggest that burn injury increases Angiopoetin-2 and downstream signaling in the lungs, which may contribute to post-burn pulmonary dysfunction. Further studies are necessary to understand if modulating the Ang–TIE2 axis can protect against pneumonia post-burn. Full article

Watercore disease, a physiological disorder in pineapple (Ananas comosus), manifests during late fruit development. Affected fruits develop water-soaked flesh and reduced storability. (1) Background: To explore underlying molecular mechanisms, comparative proteomic profiling was conducted in this study. (2) Methods: Data-independent acquisition (DIA) strategy was employed for comparative analysis between the resistant germplasm “35-1” and the susceptible germplasm “29-3”, as well as between the healthy and diseased “Paris”. (3) Results: Resistant (“35-1”) versus susceptible (“29-3”) germplasm analysis revealed differentially expressed proteins (DEPs) and unique proteins (SEPs) enriched in cell walls, secretory vesicles, and apoplast, functioning in cell wall loosening, hormone response, isoflavonoid biosynthesis, and farnesyl diphosphate biosynthesis. Healthy versus diseased “Paris” pulp analysis showed DEPs/SEPs enrichment in ribosomal small subunit biogenesis. These proteins form a central regulatory network potentially orchestrating tRNA synthesis, tubulin biosynthesis, and other carbohydrate metabolism. Partial protein overlap occurred in germplasm- and disease-derived differences. Resistant germplasm (“35-1”) and healthy “Paris” accumulated stress-responsive/resistant proteins and cell wall-modifying enzymes (e.g., phenylalanine ammonia-lyase, raffinose synthase, expansins, and mannan hydrolase). Susceptible germplasm (“29-3”) and diseased “Paris” exhibited prominent stress-responsive protein accumulation, such as alcohol dehydrogenase, 1-aminocyclopropane-1-carboxylate oxidase, and hypoxia-induced protein. (4) Conclusions: This comparative proteomics study identifies pineapple watercore resistance/susceptibility-associated proteins, providing a molecular basis for resistant germplasm development and disorder control. Full article

Objective: Airway hyperresponsiveness (AHR) is a hallmark feature of asthma; however, its precise molecular mechanisms remain incompletely defined. In this study, we investigated protein expression in airway smooth muscle that may contribute to AHR, using an experimental model of ovalbumin-induced allergic asthma. Methods: Guinea pigs were sensitized and challenged with ovalbumin. Airway responsiveness to histamine was assessed, and proteomic analysis of the tracheal tissue was conducted using electrophoresis followed by MALDI/TOF-TOF mass spectrometry. Specific protein bands corresponding to the myosin phosphatase target subunit 1 (MYPT1) were analyzed, and regulatory subunit of glycogen-targeted phosphatase 1 (RG1) was further evaluated through immunohistochemistry. Results: MYPT1, previously associated with AHR, was not detected in the proteomic analysis. Interestingly, an RG1 peptide was identified. Immunohistochemistry showed a differential expression pattern was observed for the RG1 and Rho-associated protein kinase 2 (ROCK2), both of which were significantly upregulated in airway smooth muscle and positively correlated with the degree of AHR. Moreover, a significant positive correlation was observed between RG1 and ROCK2 expression levels. MYPT1 and its phosphorylated forms (Thr⁶⁹⁶ and Thr⁸⁵⁰), along with ROCK1 immunostaining, did not differ from controls. Conclusions: These findings suggest that RG1, along with ROCK2, may play an important role in airway hyperresponsiveness characteristic of asthma. Full article

The exon junction complex (EJC) is a central mediator of post-transcriptional regulation in eukaryotes. A comprehensive, systematic analysis of EJC core genes has been lacking in Phyllostachys edulis (P. edulis). Here, we identified 147 EJC core genes across 17 plant species spanning the major green plant lineages. Phylogenetic analyses supported each family as a monophyletic clade consistent with established taxonomic relationships. Synteny analyses indicated that segmental duplication is the principal driver of EJC core gene expansion in P. edulis (Moso bamboo). Transcriptome profiling further showed that nearly all PedEJCs were engaged during rapid shoot growth, with PedY14b-D, PedY14c-D, and PedY14d-C displaying the most pronounced expression changes. During shoots’ post-harvest senescence process, PedEIF4A3s, PedY14s, and PedMAGOs were progressively downregulated, whereas PedBTZs were upregulated, indicating distinct module-level responses among EJC subunits. Only a small subset of PedEJCs responds to phytohormones and abiotic stresses. Furthermore, cis-regulatory element composition in promoter region likely shapes PedEJCs transcriptional regulation. Collectively, these findings lay the groundwork for in-depth functional dissection of PedEJCs in Moso bamboo. Full article

The 26S proteasome is the main proteolytic machinery involved in protein degradation, thereby contributing to the homeostasis and stress response of eukaryotic cells. This macromolecular complex consists of a 20S core particle assembled with one or two 19S regulatory particles. Here, we describe the Plasmodium berghei (Pb) proteasome AAA-ATPase regulatory subunit Rpt3 and demonstrate its binding to the Protein Phosphatase 1 catalytic subunit (PP1c), which is one of the major and essential parasite phosphatases. The PbRpt3 protein enhances the activity of PP1c both in vitro and in a Xenopus oocyte heterologous model. Further investigation of this model suggests that the PbRpt3-PP1c interaction may occur outside of the proteasome, and it reveals that the RVxF motifs of PbRpt3 are involved in its binding and regulatory function. Moreover, the ATP-binding capacity of PbRpt3 may also contribute to its phosphatase regulatory activity. In the parasite, reverse genetic studies suggest an essential role for PbRpt3 during erythrocytic cycle of P. berghei, and an interactome analysis confirmed that PbRpt3 belongs to the 19S regulatory particle of the proteasome and may interact with proteins previously shown to be involved in phospholipid binding. Full article

Cardioprotection refers to the natural capacity of heart tissue to resist damage under conditions such as ischemia–reperfusion and various metabolic stresses. First identified in the phenomenon of ischemic preconditioning, the concept has since broadened to encompass other triggers of protective signaling, including hypoxia, temperature shifts, and a wide range of pharmacological compounds. This expansion indicates the presence of common molecular pathways and defense mechanisms. Known intracellular contributors to cardioprotection involve numerous factors, such as protein kinases, the reperfusion injury salvage kinase (RISK) cascade, the Survivor Activating Factor Enhancement (SAFE) pathway, hypoxia-inducible factor-1α (HIF1α), microRNAs, and Connexin 43, among others. These components are crucial in initiating downstream signaling, promoting the expression of protective genes, optimizing mitochondrial function, and regulating cytosolic and protein processes to maintain cardiac resilience. Key end-effectors include SUR2A, a regulatory subunit of sarcolemmal ATP-sensitive potassium (KATP) channels, autophagy, and mitochondria. Central mechanisms, such as modulation of the mitochondrial permeability transition pore and activation of KATP channels, play essential roles in the cardioprotective response. Although significant progress has been made in mapping these networks, many facets remain poorly understood. One of the most pressing challenges is to translate this knowledge into practical therapies and eventually create clinically applicable strategies to protect the heart. Full article

Deoxynivalenol (DON, commonly known as vomitoxin) is one of the most prevalent mycotoxins contaminating feed in China, posing a serious threat to the health of piglets. Beyond intestinal damage, the liver is a key target organ for the systemic toxicity of DON, but its hepatotoxic molecular mechanisms, particularly the changes at the proteome level, remain unclear. To investigate the protein regulatory network of DON-induced liver injury in piglets, this study systematically analyzed differential expression in the liver proteome using quantitative proteomic techniques. Proteomic analysis identified 5851 proteins in total, among which 88 were differentially expressed proteins (DEPs), including 39 upregulated and 49 downregulated proteins. Bioinformatics analysis revealed that these DEPs were significantly enriched in pathways such as DNA damage repair, RNA metabolism, ribosome biogenesis, and cysteine metabolism. Suppressed expression of key proteins like Replication Factor C Subunit 4 (RFC4) and Exosome Component 9 (EXOSC9) indicated that DON exposure severely disrupted the maintenance of genomic stability and RNA processing capacity in hepatocytes. Conversely, the activation of Nucleic Acid Binding Protein 1 (NABP1) might represent a compensatory DNA protection response. Furthermore, the upregulation of Lactate Dehydrogenase B (LDHB) suggested that DON might influence epigenetic modifications by regulating lactate metabolism. This study reveals, for the first time from a proteomic perspective, a novel mechanism by which DON induces hepatotoxicity in piglets by disrupting DNA repair and RNA metabolic homeostasis, providing an important theoretical basis and data support for elucidating the toxicological effects of DON and improving feed biosafety control strategies. Full article

Alzheimer’s disease (AD) and stroke have been identified as risk factors for each other. More than half of AD patients suffer stroke attacks and worse ischemic injuries. There has been a lack of research focus and clinical treatment for the comorbidity of these neurological disorders. AD and ischemic stroke share characteristic pathophysiology, including hyperactivities of excitatory neurons and NMDA receptors (NMDARs), excitotoxicity, and synapse/neurovascular destruction. Our recent investigations identified the deficiency of the NMDAR regulatory GluN3A (NR3A) subunit as a novel pathogenesis of sporadic AD. The present investigation tested a preemptive treatment to prevent AD development in two AD models and, in the meantime, to prime the susceptible brain against upcoming ischemic attacks. In the preclinical stage of 3-month-old GluN3A KO mice, an NMDAR-mediated sporadic AD model, and 5xFAD mice, an amyloid-based familial AD model, treatments with memantine (MEM), an NMDAR antagonist (10 mg/kg/day in drinking water) and a drug-free control were started when cognition of these mice was generally normal. Three months later, the mice were subjected to focal cerebral ischemic surgery, followed by continued 1.5–2.0 months of MEM or vehicle control. Morphological, pathological, and functional assessments were performed and compared at different time points. In both AD models, the early MEM treatment confined AD progression before and after stroke, reduced ischemia-induced brain injury, suppressed neuroinflammation, and improved locomotion, sensorimotor, psychological, and cognitive functions. This is the first report endorsing a shared mechanism of NMDAR hyperactivity in AD and stroke in AD models with distinctive risk factors. The dual therapeutic effects of the preemptive MEM treatment provide a disease-modifying possibility for individuals who are susceptible to sporadic or familial AD as well as ischemic stroke. Full article

Pulmonary carcinoma remains a highly aggressive malignancy driven by complex signaling and epigenetic dysregulation. This study investigates a novel oncogenic pathway involving the Mg^2+/Mn²⁺-dependent protein phosphatase 1B PPM1B/myosin phosphatase (MP)/protein arginine methyltransferase 5 (PRMT5) axis, which promotes carcinogenesis by symmetrically dimethylating histone H2A and suppressing tumor suppressor genes. We hypothesized that loss of PPM1B would activate this pathway and drive tumorigenesis. Western blotting, PCR, and immunohistochemistry revealed a significant reduction in PPM1B expression in both squamous cell carcinoma (SCC) and human lung adenocarcinoma (ADC) compared to normal lung tissues, which correlated with worse patient survival. Despite an increase in total MYPT1, the regulatory subunit of MP, its inhibitory phosphorylation at Thr853 was significantly elevated in both tumor types. The inactivation of MP corresponded with a significant increase in the activating phosphorylation of PRMT5 at Thr80, especially in SCC, which was linked to a particularly poor prognosis. Downstream, this resulted in a dramatic elevation in the symmetric dimethylation of histone H2A, leading to decreased expression of retinoblastoma protein. Our findings demonstrate that decreased PPM1B expression drives the oncogenic activation of the MP/PRMT5 axis. This mechanism contributes to the aggressive nature of SCC, establishing PPM1B as a promising prognostic marker in lung cancer. Full article

Calcineurin (CaN), a Ca²⁺-dependent phosphatase, plays key roles in eukaryotic cell signaling. We investigated whether Leishmania amazonensis’ two infective forms—promastigotes and amastigotes—exhibit differences in CaN expression, localization, and functional impact, using two canonical inhibitors (cyclosporin A, CsA; tracolimus, FK506). At high 40 µM CsA, promastigotes showed reduced viability, whereas amastigotes remained resistant. FK506 had no effect on either form. At a sub-lethal 25 µM CsA, parasite proliferation remained unaffected. In parasite–macrophage co-incubation assays, phosphorylation patterns differed: amastigotes—but not promastigotes—showed increased serine/threonine phosphorylation upon CaN inhibition. Western blotting and in silico data revealed higher CaN catalytic (CaNA2) and regulatory (CaNB) subunit expression in amastigotes than promastigotes. Immunofluorescence localized CaNA prominently in both cytoplasm and nucleus of promastigotes, but predominantly cytoplasmic in amastigotes; CaNB was largely cytoplasmic in both. In silico localization predictions suggested strong membrane associations for CaNA in Leishmania, contrasting with mammalian models. Subcellular fractionation confirmed CaNA enrichment in membrane fractions, with CaNB in cytoplasmic and nuclear fractions. Collectively, these findings reveal form-specific differences in expression, subcellular distribution, and inhibitor responses of CaN in L. amazonensis, highlighting its potential as a stage-specific therapeutic target in leishmaniasis. Full article

The vitality of pollen significantly influences the efficiency of pollination and microspore embryogenesis. Mining genes associated with pollen vitality will help accelerate pepper (Capsicum annuum L.) breeding progress via genetic engineering. PEX (pollen extensin-like), a member of the LRX (leucine-rich repeat extensin) family, is predominantly expressed in pollen and participates in regulating pollen vitality. However, its function and regulatory factors in pepper remain elusive. In this study, GUS histochemical staining results revealed that pepper CaPEX3 could be expressed in petals, sepals, anthers, and pollens of transgenic tomato (Solanum lycopersicum L.) lines expressing CaPEX3 promoter::GUS. Moreover, inhibition of the CaPEX3 by virus-induced gene silencing (VIGS) in pepper resulted in reduced pollen germination rate and viability, while overexpression of CaPEX3 in tomato significantly enhanced germination rate and pollen viability. In addition, TRANSPARENT TESTA GLABRA 1 (CaTTG1) and Nuclear transcription factor Y subunit C9 (CaNFYC9) were screened out and identified as the upstream regulatory transcription factors of CaPEX3 through yeast one-hybrid (Y1H) screening and dual-luciferase reporter (Dual-LUC) assays. Taken together, the identification of transcription factors may reveal a more comprehensive mechanism underlying CaPEX3-mediated enhancement of pepper pollen viability. This study not only provides genetic resources for pollen viability research but also establishes a theoretical foundation for pepper breeding. Full article