Search Results (1,572)

Plasmodesmata (PD) are dynamic nanochannels interconnecting plant cells and coordinating development, nutrient distribution, and systemic defense. Their permeability is tightly regulated by callose turnover, PD-localized proteins, lipid microdomains, and endoplasmic reticulum (ER)–plasma membrane (PM) tethers, which together form regulatory nodes that gate symplastic exchange. Increasing evidence demonstrates that effectors from diverse kingdoms—fungi, oomycetes, bacteria, viruses, viroids, phytoplasmas, nematodes, insects, parasitic plants, and symbiotic microbes—converge on these same nodes to modulate PD gating. Pathogens typically suppress callose deposition or destabilize PD regulators to keep channels open, whereas mutualists fine-tune PD conductivity to balance resource exchange with host immunity. This review synthesizes current knowledge of effector strategies that remodel PD architecture or exploit PD for intercellular movement, highlighting novel cross-kingdom commonalities–callose manipulation, reprogramming of PD proteins, lipid rewiring, and co-option of ER-PM tethers. We outline unresolved questions on effector–PD target specificity and dynamics, and identify prospects in imaging, proteomics, and synthetic control of PD. Understanding how effectors reprogram PD connectivity can enable engineering of crops that block pathogenic trafficking while safeguarding beneficial symbioses. Full article

Neuromast cells are specialized mechanosensory receptor cells embedded within the lateral line system of aquatic vertebrates, enabling the detection of water movement and vibration that are essential for navigation, prey capture, and predator avoidance. These cells share common evolutionary and functional homology with mammalian inner ear hair cells, both of which rely on stereocilia-mediated mechano-transduction and ion channel activation to convert mechanical stimuli into neural signals. Unlike their mammalian counterparts, neuromast hair cells possess a regenerative capacity following damage, making the lateral line system a unique model for studying hair cell regeneration and sensory restoration. This study examines the potential of the Mexican tetra (Astyanax mexicanus) as a novel model organism for investigating ototoxicity and regeneration of neurosensory hair cells. Here, we explore the cranial and trunk lateral line neuromasts, including deep canal neuromast cells located in facial bones, such as the mandible and circumorbital bones. In the present study, juvenile surface-dwelling Mexican tetra were exposed to a 500 µM neomycin for 4 h to induce targeted hair cell damage. The samples were collected at 4-, 12-, 24-, and 72 h post-exposure. Furthermore, neuromast cell viability was assessed using [2-(4-(Dimethylamino) styryl)-N-ethylpyridinium iodide] (DASPEI). Gene expression analysis revealed a modest increase in Fibroblast Growth Factor 1 (fgf1) and Axis Inhibition Protein 2 (axin2) expression following treatment; however, these changes were not statistically significant. The SRY-box transcription factor 2 (sox2) remains constant throughout the exposure and recovery period. These findings highlighted the regenerative dynamics of neuromast cells in Mexican tetra. This work lays the foundation for future therapeutic strategies targeting human sensory deficits, particularly those involving inner ear hair cell degeneration. Full article

Background/Objectives: Low-cost portable load cell dynamometers allow for real-time assessment of muscular strength. This study evaluated the reliability and repeatability of the G-Force load cell system during isometric hip abduction and adduction in young physically active Chilean adults. Methods: In total, 24 participants (19 men, 5 women) performed two maximal voluntary contractions per movement, repeated after a 24 h interval. Measured variables included Peak Force, peak rate of force development (Peak RFD), RFD at 50, 100, and 200 ms (RFD50, RFD100, RFD200), and maximum jerk. Reliability was assessed using intraclass correlation coefficients (ICCs), standard error of measurement (SEM), coefficient of variation (CV%) and Bland–Altman plots. Results: Peak Force showed excellent within-day (ICC = 0.94–0.96) and high between-day reliability (ICC = 0.87–0.89; CV = 20–30%). Bland–Altman analysis indicated negligible bias for Peak Force in abduction (−6.54 N; 95% CI −19.55 to 6.47) and adduction (−17.57 N; 95% CI −37.24 to 2.09), confirming the absence of systematic error. Peak RFD, RFD50–200, and maximum Jerk showed moderate repeatability and lower between-day reliability (ICCs = 0.39–0.70; CVs = 34–57%), indicating higher variability in explosive force indices compared with maximal strength. Conclusions: The G-Force load cell reliably measures maximal isometric hip strength, while Peak RFD, RFD50–200, and maximum jerk should be interpreted cautiously. These findings support the device as a practical, low-cost tool for sports and rehabilitation, though future studies should validate dynamic indices in larger and more diverse populations. Full article

Background/Objectives: Transferrin is a multi-task protein commonly known for binding iron; however, it is involved in multiple crucial processes, including antimicrobial activity, the growth of different cell types, differentiation, chemotaxis, the cell cycle, and cytoprotection. Vascular cell adhesion molecule 1 (VCAM-1) is a cell surface glycoprotein which participates in inflammation and the trans-endothelial movement of leukocytes. Neither transferrin nor VCAM-1 has been studied in the context of progressive supranuclear palsy (PSP) or corticobasal syndrome (CBS). This study aimed to evaluate the utility of transferrin and VCAM-1 assessment for the in vivo examination of tauopathic atypical Parkinsonian syndromes. Methods: This study included 10 patients with clinically probable PSP-RS, 10 with clinically probable PSP-P, and 8 with probable CBS. Patients’ blood and urine were collected and analyzed. Twenty-four serum samples (from twelve males and twelve females) were obtained from age-matched healthy volunteers. Peripheral blood inflammatory ratios, including the neutrophil-to-lymphocyte ratio, the platelet-to-lymphocyte ratio, the neutrophil-to-monocyte ratio, the neutrophil-to-high-density lipoprotein ratio, and the monocyte-to-high-density lipoprotein ratio, were calculated. VCAM-1 and transferrin concentrations were measured in the serum and urine. The urinary biomarker results are not included in the main analysis due to the absence of a control group. Results: The highest concentrations of transferrin in the serum were observed in patients with PSP-P, followed by PSP-RS and CBS. Statistically significant differences were found between PSP-P and healthy controls (p < 0.0001) and PSP-RS and healthy controls (p < 0.0001). The highest levels of serum VCAM-1 were observed in the PSP-P group. Significant differences were found between PSP-P and healthy controls (p < 0.0001), PSP-P and CBS (p < 0.001), and PSP-RS and healthy controls (p < 0.001). Serum VCAM-1 levels were negatively correlated with the NLR in CBS patients (p < 0.03; r = −0.74). Serum transferrin levels were negatively correlated with the NHR in CBS patients (p < 0.04; r = −0.64). ROC curve analyses were conducted to evaluate the diagnostic utility of serum transferrin and VCAM-1 in distinguishing tauopathic APS patients from controls. Transferrin showed excellent diagnostic performance, with an AUC of 0.975 (95% CI: 0.888–0.999; p < 0.0001), a sensitivity of 96.4%, and a specificity of 95.8% at the optimal cut-off (>503.0). VCAM-1 demonstrated good accuracy, with an AUC of 0.839 (95% CI: 0.711–0.926; p < 0.0001), a sensitivity of 75.0%, and a specificity of 91.7% at the optimal cut-off (>463.9). Conclusions: The obtained results indicate the potential role of transferrin and VCAM-1 in the pathogenesis of tauopathic APSs and highlight the need for further exploration in this field. Full article

Background: Innovative interventions, such as social media platforms and telemedicine, were implemented during the COVID-19 lockdown period for HIV prevention and treatment services. However, limited studies have reported on the facilitators and barriers of these innovations for HIV pre-exposure prophylaxis (PrEP) service continuity. Therefore, this study aimed to identify the barriers and facilitators of the implemented PrEP innovative interventions during COVID-19 among adolescent girls and young women (AGYW). Methods: A qualitative exploratory design was used to conduct semi-structured interviews with twelve stakeholders in the Dr Kenneth Kaunda District, North West Province of South Africa. Participants included various TB HIV Care programme stakeholders, comprising professional nurses, case managers, peer educators, and counsellors. The Consolidated Framework for Implementation Research (CFIR) 2.0 domains and constructs guided the interview questions and the analysis process. Additionally, all interviews were audio-taped, transcribed verbatim, and analyzed through thematic analysis. The facilitators and barriers of the PrEP innovative interventions were categorized according to the five CFIR domains. Results: The findings showed that despite the COVID-19 disruptions in healthcare services, the implemented innovative PrEP interventions enhanced the HIV prevention services. Facilitators included sufficient mobile data, teamwork, clear communication from managers, resilience, and existing media pages that supported social media-based PrEP service continuity. The implementation barriers included service users’ lack of cell phone devices, incorrect personal information, fear of contracting COVID-19, and limited individual movements. Conclusion: Social media and digital technologies played a crucial role in the continuation of HIV PrEP services among AGYW. These evaluations also illustrated the potential of social media platforms to be leveraged for HIV service delivery during periods of disruption, such as the COVID-19 lockdown period, for HIV service delivery. Furthermore, lessons learned from this study are significant and offer practical considerations for sustaining PrEP during service disruptions. Full article

Chloroplasts, which are essential for plant defense and phytohormone signaling, contain ribosomal proteins that play key roles in viral infection processes. Plastid-specific ribosomal proteins (PSRPs), unique to chloroplasts, remain unexplored in their mechanistic roles during plant-virus interactions. In this study, we identified two PSRPs from non-heading Chinese cabbage (Brassica campestris ssp. chinensis) as interacting with turnip mosaic virus (TuMV, Potyvirus rapae). Subcellular localization revealed that BcPSRP2/4 is targeted to chloroplasts, while BiFC, Y2H, and LCAs confirmed their interaction with TuMV VPg (virus protein, genome-linked). Intriguingly, VPg altered the subcellular localization of BcPSRP2/4, suggesting an important role for BcPSRP2/4 in TuMV infection. Strikingly, overexpression of BcPSRP2/4 enhanced TuMV cell-to-cell movement, while psrp2 knockdown mutants in Arabidopsis exhibited a significant reduction in viral accumulation, highlighting their proviral roles. Furthermore, virus-induced gene silencing (VIGS)-mediated suppression of BcPSRP2/4 in non-heading Chinese cabbage resulted in milder symptoms upon TuMV infection without compromising plant growth: a distinct advantage over conventional resistance genes that incur fitness costs. These findings highlight PSRP2/4 as pivotal molecular hinges in chloroplast-virus interplay, offering novel targets for engineering sustainable antiviral strategies in cruciferous crops. Full article

The localization and remodeling of mRNPs is inextricably linked to translational control. In recent years there has been great progress in the field of mRNA translational control due to the characterization of the proteins and small RNAs that compose mRNPs. But our initial assumptions about the physical nature and participation of germ cell granules/condensates in mRNA regulation may have been misguided. These “granules” were found to be non-membrane-bound liquid–liquid phase-separated (LLPS) condensates that form around proteins with intrinsically disordered regions (IDRs) and RNA. Their macrostructures are dynamic as germ cells differentiate into gametes and subsequently join to form embryos. In addition, they segregate translation-repressing RNA-binding proteins (RBPs), selected eIF4 initiation factors, Vasa/GLH-1 and other helicases, several Argonautes and their associated small RNAs, and frequently components of P bodies and stress granules (SGs). Condensate movement, separation, fusion, and dissolution were long conjectured to mediate the translational control of mRNAs residing in contained mRNPs. New high-resolution microscopy and tagging techniques identified order in their organization, showing the segregation of similar mRNAs and the stratification of proteins into distinct mRNPs. Functional transitions from repression to activation seem to corelate with the overt granule dynamics. Yet increasing evidence suggests that the resident mRNPs, and not the macroscopic condensates, exert the bulk of the regulation. Full article

During embryonic development, angiogenesis and arteriogenesis are responsible for vast growth and remodeling. These processes have distinct mechanisms, like budding, cord hollowing, cell hollowing, cell wrapping, and intussusception. This review discusses the diversity of morphogenetic mechanisms contributing to vessel assembly and angiogenic sprouting in blood vessels and how molecular pathways regulate some complex cell behaviors concerning the VEGFR pathway. Also, a particular part is dedicated to the HIF 1α gene. The key components of the VEGFR pathway are VEGF receptors VEGFR1, VEGFR2, and VEGFR3. VEGFR2 plays a central role in vascular morphogenesis. VEGF is the primary ligand involved in angiogenesis and arteriogenesis. Various types of VEGF are being studied in terms of their therapeutic use. The ultimate goal of the vascular morphogenesis study is to enable the development of organized vascular tissue that presumably might be used to replace the diseased one. Cellular chirality—the intrinsic “handedness” of cells in movement, structure, and organization—plays a crucial role in angiogenesis, the process by which new blood vessels develop from old ones. This chiral activity is essential for the directed and patterned organization of endothelial cells during vascular formation and remodeling. In angiogenesis, cellular chirality directs endothelial cells to adopt specific orientations and migratory patterns, which are crucial for the formation of functionally organized blood vessels that provide tissues with the necessary nutrients and oxygen. Cellular chirality in this environment is affected by multiple mechanisms, including VEGF/VEGFR signaling, mechanical pressures, interactions with the extracellular matrix (ECM), and cytoskeletal movements. Lately, researchers have focused on the molecular control of blood vessel morphogenesis, the study of signaling circuitry implied in vascular morphogenesis, the emerging mechanism of vascular stabilization, and helical vasculogenesis driven by cell chirality. Full article

Imaging of intracellular messengers, like calcium, is one of the most reliable methods to follow real-time changes in several aspects of cellular activity, like receptor activation. However, the analysis could be influenced and biased by several factors like the location, shape, and size of the regions of interest (ROIs) and by the detection and correction of the movement of the preparation. Programs which are provided by the manufacturers are expensive and cannot be shared by collaborators. Many self-made programs have been implemented lately which have in-built cell recognizer ROI identification functions. These programs focus on the soma of the cells and neglect the processes, because in full tissue preparation finding cells is still challenging. Subcellular imaging experiments are still rare. To the best of our knowledge there is no program which can automatically define ROIs for subcellular imaging experiments even in single indicated cells with complex morphology. We developed and validated a program to address this gap using simple and understandable mathematical methods for ROI determination and simple statistics for movement correction. Validation experiments were conducted on cochlear Deiters’ cells. Deiters’ cells have processed morphology which connects two fluid compartments in the cochlea. Because of the function and the fine morphology of the cell, it could be interesting to examine the subcellular Ca²⁺ handling mechanisms of it. Test impulses were activated by ATP. With some limitations the program successfully fulfilled its purpose. As a free, easily understandable, and open-source program, we hope it will help to analyze and plan subcellular experiments. Full article

Orthodontic tooth movement (OTM) arises from force-induced mechanotransduction within the periodontal ligament (PDL), which coordinates osteoblast and osteoclast activity with immune responses to remodel the PDL and alveolar bone. This review integrates contemporary biological insights on OTM and assesses photobiomodulation (PBM) as an adjunctive therapy. We propose that mechanical and photonic inputs may interact and potentiate signaling through the Ca²⁺-NFAT, MAPK (ERK, p38, JNK), PI3K–Akt–mTOR, NF-kB, TGF-β/Smad, and Wnt/β-catenin pathways. Such interaction could influence processes such as cell proliferation, differentiation, specific cellular functions, apoptosis, autophagy, and communication between stromal and immune cells. This convergence establishes a solid foundation for understanding the context-dependent effects of PBM in OTM. In principle, PBM appears most effective as a phase-tuned adjunct, promoting early inflammatory recruitment of osteoclasts and subsequently facilitating late-phase remodeling through immunomodulatory and reparative mechanisms. However, inconsistent irradiation parameters, small sample sizes, trial heterogeneity, and the absence of mechanistic endpoints undermine current conclusions. Furthermore, the lack of integrated PBM–OTM models limits mechanistic understanding, as much of the available evidence is derived from non-OTM contexts. Overall, PBM remains a promising adjunct in orthodontics, with the potential to integrate mechanical and photonic signals in a phase-dependent manner, though its application is not yet standardized. Full article

MicroRNA (miRNA), as a key post-transcriptional regulatory factor, plays a crucial role in embryonic development. The coordination of endoderm cell convergence and cardiac precursor cell (CPC) migration is critical for cardiac tube fusion. Defects in endoderm can impair the normal migration of CPCs towards the midline, leading to cardia bifida. Although the role of the microRNA-183 family (miR-183, miR-96 and miR-182) in cardiovascular diseases has been reported, the mechanism by which they regulate early heart development remains unclear. In this study, we used zebrafish as a model to elucidate the roles of the microRNA-183 family in early heart development. miRNA mimics were injected into Tg (cmlc2: eGFP) and Tg (sox17: eGFP) transgenic embryos to overexpress the miR-183 family. The results showed that, at 36 hpf, single or co-injection of miR-183/96/182 mimics caused defects in endoderm convergence, with a hole in the endoderm, and a significant down-regulation of the endoderm marker gene sox32. Additionally, embryos with single or co-injection of miR-183/96/182 mimics exhibited cardia bifida and tail blisters, with significantly down-regulated expression levels of genes related to heart development, including cmlc2, vmhc, amhc, nppa, gata4, gata5, nkx2.5, bmp2b, and bmp4. The phenotype caused by overexpression of the miR-183 family is highly consistent with loss of the sphingosine 1-phosphate receptor S1Pr2. Bioinformatics analysis result found that miR-183 can bind to 3′-UTR of the s1pr2 to regulate its expression; overexpression of miR-183 led to a significant decrease in the expression of the s1pr2 gene. Dual luciferase assay results suggest that s1pr2 is a bona fide target of miR-183. In summary, the miR-183 family regulates endoderm convergence and cardiac precursor cell migration via the S1Pr2 signaling pathway. This study reveals that the miR-183 family is a key regulatory factor in endoderm convergence and cardiac precursor cell migration during the early zebrafish development, elucidating the molecular mechanisms underlying early cardiac precursor cell and endoderm cell movement. Full article

Parkinson’s disease (PD) is characterized by degeneration of nigrostriatal dopaminergic neurons (DNs) and movement disorders. Low efficiency of pharmacotherapy requires improvement, e.g., using receptor agonists or antagonists as drugs. Our work aims to initiate these developments by studying the expression levels of genes encoding neurotransmitters, neuropeptides and hormone receptors in substantia nigra pars compacta (SNpc) cells and in isolated DNs in intact mice, and changes in expression of these genes in MPTP mouse models of PD at preclinical and clinical stages. Expression of all 12 studied genes was detected in the SNpc and only 10 in DNs—Cckar and Glp1r were undetectable. In intact mice, the expression of Drd2, Grin2b, Grm1 and Ntsr2 predominates in SNpc tissue, whereas that of Gria2, Chrnb2, Gper1, Igf1r is higher in DNs. In PD models, change in receptor gene expression was detected in DNs but not in SNpc tissue. In the preclinical PD, Drd2 expression increased and Gria2 decreased, whereas in a clinical model, Drd2, Grm1, Ntsr2 expression decreased. Thus, the above genes are expressed in DNs and other cells of SNpc; expression of some genes changes in PD models, which opens up prospects for development of therapy using receptor agonists and antagonists. Full article

Neurodegenerative diseases (NDDs) are a group of progressive diseases affecting neuronal cells in specific areas of the brain, causing cognitive decline and movement impairment. Nowadays, NDDs play a significant role in the global burden of disease, and their incidence is increasing, particularly due to population aging. NDD onset is multi-factorial; based on the current knowledge, genetic, environmental, and cellular factors are believed to contribute to their occurrence and progression. Taking into account that at an early stage, the symptoms are not clearly defined, and diagnosis may be delayed, the development of innovative and non-invasive methodological approaches for early diagnosis of NDDs is strategic for timely and tailored disease management, as well as for the overall improvement of patients’ quality of life. The present review aims to provide, in the first part, an overview based on the current level of knowledge on the environmental risk factors that can explicate a role in the onset of the most common NDDs and on the main pathogenic mechanisms involved in disease initiation and progression. The second part aims to define the current state of the art regarding the significance of Volatile Organic Compounds (VOCs) in the volatome of different human biological matrices (exhaled breath, feces, and skin sebum) as candidate biomarkers of specific NDDs, with the aim of developing non-invasive diagnostic approaches for the early diagnosis and personalized management of the patients. A critical synthesis and discussion on the applied methodological approaches and on the relevant outcomes obtained across the studies is reported. Full article

The deposition of amyloid beta (Aβ) in the human brain is a hallmark of Alzheimer’s disease (AD). Aβ has been shown to exert a wide range of effects on neurons in cell and animal models. Here, we take advantage of differentiated neurons from iPSC-derived neural stem cells of human donors to examine its effects on human neurons. Specifically, we employed two types of neurons from genetically distinct donors: one male carrying APO E2/E2 (M E2/E2) and one female carrying APO E3/E3 (F E3/E3). Genome-wide RNA-sequencing analysis identified 64 and 44 genes that were induced by Aβ in M E2/E2 and F E3/E3 neurons, respectively. GO and pathway analyses showed that Aβ-induced genes in F E3/E3 neurons do not constitute any statistically significant pathways whereas Aβ-induced genes in M E2/E2 neurons constitute a complex network of activated pathways. These pathways include those promoting inflammatory responses, such as IL1β, IL4, and TNF, and those promoting cell migration and movement, such as chemotaxis, migration of cells, and cell movement. These results strongly suggest that the effects of Aβ on neurons are highly dependent on their genetic background and that Aβ can promote strong responses in inflammation and cell migration in some, but not all, neurons. Full article

Several genetic diseases affecting the human nervous system are incurable and insufficiently understood. Among them, nine rare diseases form the polyglutamine (polyQ) family: Huntington’s disease (HD), spinocerebellar ataxia types 1, 2, 3, 6, 7, and 17, dentatorubral pallidoluysian atrophy, and spinal and bulbar muscular atrophy. In most patients, these diseases progress over decades to cause severe movement incoordination and neurodegeneration. Although their inherited genes with tandem-repeat elongations and the encoded polyQ-containing proteins have been extensively studied, the neuronal-type-specific pathologies and their long pre-symptomatic latency await further investigations. However, recent advances in detecting the single-nucleus transcriptome, alongside the length of tandem repeats in HD post-mortem brains, have enabled the identification of very high CAG repeat sizes that trigger transcriptional dysregulation and cell death in specific projection neurons. One challenge is to better understand the complexity of movement coordination circuits, including the basal ganglia and cerebellum neurons, which are most vulnerable to the high CAG expansion in each disease. Another challenge is to detect dynamic changes in CAG repeat length and their effects in vulnerable neurons at single-cell resolution. This will offer a platform for identifying pathological events in vulnerable long projection neurons and developing targeted therapies for all tandem-repeat expansions affecting the CNS projection neurons. Full article