Formation and evolution of thermokarst landslides in the Qinghai-Tibet Plateau, China.

Thermokarst landslide (TL) activity in the Qinghai-Tibet Plateau (QTP) is intensifying due to climate warming-induced permafrost degradation. However, the mechanisms driving landslide formation and evolution remain poorly understood. This study investigates the spatial distribution, annual frequency, and monthly dynamics of TLs along the Qinghai-Tibet engineering corridor (QTEC), in conjunction with in-situ temperature and rainfall observations, to elucidate the interplay between warming, permafrost degradation, and landslide activity. Through the analysis of high-resolution satellite imagery and field surveys, we identified 1298 landslides along the QTEC between 2016 and 2022, with an additional 386 landslides recorded in a typical landslide-prone sub-area. In 2016, 621 new active-layer detachments (ALDs) were identified, 1.3 times the total historical record. This surge aligned with unprecedented mean annual and August temperatures. The ALDs emerged primarily between late August and early September, coinciding with maximum thaw depth. From 2016 to 2022, 97.8 % of these ALDs evolved into retrogressive thaw slumps (RTSs), identified as active landslides. Landslides typically occur in alpine meadows at moderate altitudes and on gentle northward slopes. The thick ice layer near the permafrost table serves as the material basis for ALD occurrence. Abnormally high temperature significantly increased the active layer thickness (ALT), resulting in melting of the ice layer and formation of a thawed interlayer, which was the direct causing factor for ALD. By altering the local material, micro-topography, and thermal conditions, ALD activity significantly increases RTS susceptibility. Understanding the mechanisms of ALD formation and evolution into RTS provides a theoretical foundation for infrastructure development and disaster mitigation in extreme environments.

The novel TFEB agonist desloratadine ameliorates hepatic steatosis by activating the autophagy-lysosome pathway.

The autophagy-lysosome pathway plays an essential role in promoting lipid catabolism and preventing hepatic steatosis in non-alcoholic fatty liver disease (NAFLD). Transcription factor EB (TFEB) enhances the autophagy-lysosome pathway by regulating the expression of genes related to autophagy and lysosome biogenesis. Therefore, targeting TFEB provides a novel strategy for the treatment of lipid metabolic diseases. In this study, the antiallergic drug desloratadine was screened and identified as a novel TFEB agonist. Desloratadine effectively induced translocation of TFEB to the nucleus and promoted autophagy and lysosome biogenesis. Desloratadine-induced TFEB activation was dependent on AMPK rather than mTORC1. Moreover, desloratadine treatment enhanced clearance of lipid droplets in cells induced by fatty acids oleate and palmitate. Furthermore, high-fat diet (HFD) induced obesity mouse model experiments indicated treatment with desloratadine markedly reduced the body weight of HFD-fed mice, as well as the levels of hepatic triglycerides and total cholesterol, serum glutamic pyruvic transaminase and glutamic-oxaloacetic transaminase. Oil red O staining showed the liver fat was significantly reduced after desloratadine treatment, and H&E staining analysis demonstrated hepatocellular ballooning was improved. In addition, autophagy and lysosomal biogenesis was stimulated in the liver of desloratadine treated mice. Altogether, these findings demonstrate desloratadine ameliorates hepatic steatosis through activating the TFEB-mediated autophagy-lysosome pathway, thus desloratadine has an exciting potential to be used to treat fatty liver disease.

Clinical efficacy of enhanced recovery surgery in Da Vinci robot-assisted pancreatoduodenectomy.

Da Vinci robot-assisted pancreaticoduodenectomy offers advantages, including minimal invasiveness, precise, and safe procedures. This study aimed to investigate the clinical effectiveness of implementing enhanced recovery after surgery (ERAS) concepts in Da Vinci robot-assisted pancreaticoduodenectomy. A retrospective analysis was conducted on clinical data from 62 patients who underwent Da Vinci robot-assisted pancreaticoduodenectomy between January 2018 and December 2022. Among these patients, 30 were managed with ERAS principles, while 32 were managed using traditional perioperative management protocols. Surgical time, intraoperative blood loss, postoperative oral intake time, time to return of bowel function, time to ambulation, visual analog scale (VAS) pain scores, fluid replacement volume, length of hospital stay, total hospital expenses, complications, and patient satisfaction were recorded and compared between the two groups. Postoperative follow-up included assessment of postoperative functional scores, reoperation rates, SF-36 quality of life scores, and survival rates. The average follow-up time was 35.6 months (range: 12-56 months). There were no statistically significant differences in general characteristics, including age, surgical time, intraoperative blood loss, and preoperative medical history between the two groups (P > 0.05). Compared to the control group, the intervention group had an earlier postoperative oral intake time, faster return of bowel function, rapid ambulation, and shorter hospital stays (P < 0.05). The intervention group also had lower postoperative VAS scores, lower fluid replacement volume, lower total hospital expenses, and a lower rate of complications (P < 0.05). Patient satisfaction was higher in the intervention group (P < 0.05). There were no statistically significant differences between the two groups in two-year functional scores, reoperation rates, quality of life scores, and survival rates (P > 0.05). Implementing ERAS principles in Da Vinci robot-assisted pancreaticoduodenectomy substantially expedited postoperative recovery, lowered pain scores, and diminished complications. However, there were no notable differences in long-term outcomes between the two groups.

Effect of siaD on Ag-8 to improve resistance to crown gall in grapes and related mechanisms.

Crown gall caused by Agrobacterium vitis (A. vitis) is one of the crucial issues restricting the to grape industry. In this study, Agrobacterium tumefaciens (Ag-8) was separated from the soil that could prevent the occurrence of grape crown gall. By the mutagenesis of Ag-8 transposon, the siaD gene deletion strain (ΔsiaD) showed significantly lower efficacy in grape and tomato plants for controlling grape crown gall, but the relevant mechanism was not clear. The biofilm formation and motility of ΔsiaD were significantly decreased, and the colonization ability of ΔsiaD in tomato roots was significantly reduced. RNA-seq analysis showed that the expression of nemR significantly reduced in the ΔsiaD and that the expression of nemR showed a high correlation with biofilm and motility. Further studies showed that the nemR gene deletion strain of Ag-8 (ΔnemR) showed significantly reduced motility, biofilm formation and control of grape crown gall compared to Ag-8, and the nemR gene complementary strain of Ag-8 (ΔnemR-comp) recovered to Ag-8 wild-type levels. The inoculation experiments of preventive, curative or simultaneous treatment further showed that the preferential inoculation with Ag-8 reduced the incidence of grape crown gall on tomato plants, and studies showed that the mutation of siaD affected the site competition between Ag-8 and A. vitis, and that the mutation of nemR was consistent with the previous results. This study provides a new strategy for the prevention and control of grape crown gall, which is of great significance to the grape industry to increase production and income.

Nomogram model for the diagnosis of solitary nodular pulmonary mucinous adenocarcinoma.

The objective of this study was to develop a nomogram model based on the natural progression of tumor and other radiological features to discriminate between solitary nodular pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinomas. A retrospective analysis was conducted on 15,655 cases of lung adenocarcinoma diagnosed at our institution between January 2010 and June 2023. Primary nodular invasive mucinous adenocarcinomas and non-mucinous adenocarcinomas with at least two preoperative CT scans were included. These patients were randomly assigned to training and validation sets. Univariate and multivariate analyses were employed to compare tumor growth rates and clinical radiological characteristics between the two groups in the training set. A nomogram model was constructed based on the results of multivariate analysis. The diagnostic value of the model was evaluated in both the training and validation sets using calibration curves and receiver operating characteristic curves (ROC). The study included 174 patients, with 58 cases of mucinous adenocarcinoma and 116 cases of non-mucinous adenocarcinoma. The nomogram model incorporated the maximum tumor diameter, the consolidation/tumor ratio (CTR), and the specific growth rate (SGR) to generate individual scores for each patient, which were then accumulated to obtain a total score indicative of the likelihood of developing mucinous or non-mucinous adenocarcinoma. The model demonstrated excellent discriminative ability with an area under the receiver operating characteristic curve of 0.784 for the training set and 0.833 for the testing set. The nomogram model developed in this study, integrating SGR with other radiological and clinical parameters, provides a valuable and accurate tool for differentiating between solitary nodular pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinomas. This prognostic model offers a robust and objective basis for personalized management of patients with pulmonary adenocarcinomas.

Serum copper assessment in patients with polycystic ovary syndrome and tubal infertility: A retrospective 5-year study.

The association between serum copper and polycystic ovary syndrome (PCOS) lacks definitive conclusions, and the intricate interactions with in vitro fertilization (IVF) cycle characteristics in infertility remain insufficiently explored. This retrospective study included 560 patients with tubal infertility (no-PCOS) and 266 patients with PCOS undergoing IVF at the Affiliated Suzhou Hospital of Nanjing Medical University from January 2018 to December 2022. Patients' basic characteristics, hormonal and metabolic parameters, essential trace elements, and IVF cycle characteristics were measured and analyzed. The results revealed a significantly elevated serum copper level in the PCOS group compared to the control group [17.27 (15.54, 19.67) vs 15.4 (13.87, 17.35), µmol/L; p < .001]. Spearman correlation analyses revealed a significant positive correlation between serum copper concentration and body mass index (BMI), fasting glucose (FG), triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL) in the no-PCOS group. Additionally, a notable negative correlation with high-density lipoprotein (HDL) was observed (r = -.184, p < .001). Within the PCOS group, serum copper concentration correlated significantly with BMI (r = .198, p = .004) and TG (r = .214, p = .002). The linear trend analysis indicated no significant relationship between serum copper concentration and ovarian response as well as preimplantation outcomes in both groups after adjusting for confounding factors. Our study provided evidence of elevated serum copper concentration in PCOS patients, closely associated with lipid metabolism but showing no correlation with IVF outcomes. These findings provide valuable real-world data, enriching our nuanced understanding of the role of copper in female fertility.

Novel Mito-Nuclear Combinations Facilitate the Global Invasion of a Major Agricultural Crop Pest.

A fundamental understanding of the underlying mechanisms involved in biological invasions is crucial to developing effective risk assessment and control measures against invasive species. The fall armyworm (FAW), Spodoptera frugiperda, is a highly invasive pest that has rapidly spread from its native Americas into much of the Eastern Hemisphere, with a highly homogeneous nuclear genetic background. However, the exact mechanism behind its rapid introduction and propagation remains unclear. Here, a systematic investigation is conducted into the population dynamics of FAW in China from 2019 to 2021 and found that FAW individuals carrying "rice" mitochondria (FAW-mR) are more prevalent (>98%) than that with "corn" mitochondria (FAW-mC) at the initial stage of the invasion and in newly-occupied non-overwintering areas. Further fitness experiments show that the two hybrid-strains of FAW exhibit different adaptions in the new environment in China, and this may have been facilitated by amino acid changes in mitochondrial-encoded proteins. FAW-mR used increases energy metabolism, faster wing-beat frequencies, and lower wing loadings to drive greater flight performance and subsequent rapid colonization of new habitats. In contrast, FAW-mC individuals adapt with more relaxed mitochondria and shuttle energetics into maternal investment, observed as faster development rate and higher fecundity. The presence of two different mitochondria types within FAW has the potential to significantly expand the range of damage and enhance competitive advantage. Overall, the study describes a novel invasion mechanism displayed by the FAW population that facilitates its expansion and establishment in new environments.

Genome-wide DNA methylation profile and its function in regulating Vip3Aa tolerance in fall armyworm (Spodoptera frugiperda).

BACKGROUND: Vegetative insecticidal proteins (Vips) are widely used in pest management, but Vip tolerance poses a significant threat. DNA methylation plays important roles in regulating the response of biological organisms to environmental stress, and it may also regulate fall armyworm (FAW, Spodoptera frugiperda) Vip3Aa tolerance. RESULTS: In this study, a DNA methylation map was developed for FAW, and its function in regulating FAW Vip3Aa tolerance was explored. The FAW genome-wide DNA methylation map showed that exons were preferred regions for DNA methylation and housekeeping genes were highly methylated. FAW was screened using Vip3Aa for ten generations, and bioassays indicated that Vip3Aa tolerance increased trans-generationally. A comparison of DNA methylation maps between Vip3Aa-tolerant and -susceptible strains showed that gene body methylation was positively correlated with gene expression level. FAW exhibits significant variation in DNA methylation among individuals, and Vip3Aa screening induces epigenetic variation based on DNA methylation. Moreover, the study demonstrated that a reduction in methylation density within the gene body of a 3'5'-cyclic nucleotide phosphodiesterase gene resulted in decreased expression and increased tolerance of FAW to Vip3Aa, which was validated through RNA interference experiments. CONCLUSION: The DNA methylation map and mechanism of Vip3Aa tolerance improve our understanding of DNA methylation and its function in Lepidoptera and provide a new perspective for developing pest management strategies. © 2024 Society of Chemical Industry.

Improving bee feed recipes to safeguard honeybee colonies during times of food scarcity.

In beekeeping, when natural nectar or pollen sources become limited, it is crucial to provide supplemental bee feed to maintain the viability of the bee colony. This study was conducted during the autumn food shortage season, during which bees were fed with different proportions of modified bee feed. We identified an optimal bee diet by evaluating honeybee longevity, food consumption, body weight, and gut microbe distribution, with natural pollen serving as a control diet. The results indicated that bees preferred a mixture of 65% defatted soy flour, 20% corn protein powder, 13% wheat germ flour, 2% yeast powder, and a 50% sucrose solution. This bee food recipe significantly increased the longevity, feed consumption, and body weight of bees. The group fed the natural pollen diet exhibited a greater abundance of essential intestinal bacteria. The bee diets used in this study contained higher protein levels and lower concentrations of unsaturated fatty acids and vitamins than did the diets stored within the colonies. Therefore, we propose that incorporating both bee feed and natural pollen in beekeeping practices will achieve more balanced nutritional intake.

Mn(II)-Catalyzed Markovnikov Hydroiodination of Terminal Aryl Alkynes.

A Mn(II)-catalyzed Markovnikov hydroiodination of terminal aryl alkynes with TMSI as the iodination reagent has been developed. Cheap Mn(OAc)2·4H2O was employed as the catalyst. Twenty-five aryl alkynes (including two internal alkynes) were successfully transformed into their α-iodide styrene derivatives, including those natural product-based alkynes and poly alkynyl benzenes. The reaction has good chemoselectivity of alkynes over alkenes, which enabled the tolerance of olefin in the substrate. Gram-scale synthesis was also conducted.

Retrotransposon-mediated disruption of a chitin synthase gene confers insect resistance to Bacillus thuringiensis Vip3Aa toxin.

The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa.

Being Stung Once or Twice by Bees (Apis mellifera L.) Slightly Disturbed the Serum Metabolome of SD Rats to a Similar Extent.

In most cases, the number of honeybee stings received by the body is generally small, but honeybee stings can still cause serious allergic reactions. This study fully simulated bee stings under natural conditions and used 1H Nuclear Magnetic Resonance (1H NMR) to analyze the changes in the serum metabolome of Sprague-Dawley (SD) rats stung once or twice by honeybees to verify the impact of this mild sting on the body and its underlying mechanism. The differentially abundant metabolites between the blank control rats and the rats stung by honeybees included four amino acids (aspartate, glutamate, glutamine, and valine) and four organic acids (ascorbic acid, lactate, malate, and pyruvate). There was no separation between the sting groups, indicating that the impact of stinging once or twice on the serum metabolome was similar. Using the Principal Component Discriminant Analysis ( PCA-DA) and Variable Importance in Projection (VIP) methods, glucose, lactate, and pyruvate were identified to help distinguish between sting groups and non-sting groups. Metabolic pathway analysis revealed that four metabolic pathways, namely, the tricarboxylic acid cycle, pyruvate metabolism, glutamate metabolism, and alanine, aspartate, and glutamate metabolism, were significantly affected by bee stings. The above results can provide a theoretical basis for future epidemiological studies of bee stings and medical treatment of patients stung by honeybees.

Lewis acid catalyzed Markovnikov hydrobromination and hydrochlorination of alkynes using TMSX (X = Br, Cl).

Markovnikov hydrobromination and hydrochlorination of alkynes were achieved using TMSX (X = Br, Cl) instead of corrosive HX (X = Br, Cl) as the bromination and chlorination reagents. Mn(OAc)2·4H2O was used as the hydrobromination catalyst for electron-neutral/rich alkynes. For the hydrobromination of electron-deficient alkynes and hydrochlorination of alkynes, Zn(OAc)2·2H2O was employed as the catalyst. Mechanistic studies suggested that the in situ formed TMS-substituted alkyne might be a reactive intermediate and the proton of the terminal alkyne should be a hydrogen source for the hydrohalogenation reaction.

Loss of function variant in CIP2A associated with female infertility with early embryonic arrest and fragmentation.

BACKGROUND: Early embryonic arrest and fragmentation (EEAF) is a common cause of female infertility, but the genetic causes remain to be largely unknown. CIP2A encodes the cellular inhibitor of PP2A, playing a crucial role in mitosis and mouse oocyte meiosis. METHODS: Exome sequencing and Sanger sequencing were performed to identify candidate causative genes in patients with EEAF. The pathogenicity of the CIP2A variant was assessed and confirmed in cultured cell lines and human oocytes through Western blotting, semi-quantitative RT-PCR, TUNEL staining, and fluorescence localization analysis. FINDINGS: We identified CIP2A (c.1510C > T, p.L504F) as a novel disease-causing gene in human EEAF from a consanguineous family. L504 is highly conserved throughout evolution. The CIP2A variant (c.1510C > T, p.L504F) reduced the expression level of the mutant CIP2A protein, leading to the abnormal aggregation of mutant CIP2A protein and cell apoptosis. Abnormal aggregation of CIP2A protein and chromosomal dispersion occurred in the patient's oocytes and early embryos. We further replicated the patient phenotype by knockdown CIP2A in human oocytes. Additionally, CIP2A deficiency resulted in decreased levels of phosphorylated ERK1/2. INTERPRETATION: We first found that the CIP2A loss-of-function variant associate with female infertility characterized by EEAF. Our findings suggest the uniqueness and importance of CIP2A gene in human oocyte and early embryo development. FUNDING: This work was supported by National Key Research and Development Program of China (2023YFC2706302), the National Natural Science Foundation of China (81000079, 81170165, and 81870959), the HUST Academic Frontier Youth Team (2016QYTD02), and the Key Research of Huazhong University of Science and Technology, Tongji Hospital (2022A20).

Validation of mitochondrial biomarkers and immune dynamics in polycystic ovary syndrome.

PROBLEM: Polycystic ovary syndrome (PCOS), a prevalent endocrine-metabolic disorder, presents considerable therapeutic challenges due to its complex and elusive pathophysiology. METHOD OF STUDY: We employed three machine learning algorithms to identify potential biomarkers within a training dataset, comprising GSE138518, GSE155489, and GSE193123. The diagnostic accuracy of these biomarkers was rigorously evaluated using a validation dataset using area under the curve (AUC) metrics. Further validation in clinical samples was conducted using PCR and immunofluorescence techniques. Additionally, we investigate the complex interplay among immune cells in PCOS using CIBERSORT to uncover the relationships between the identified biomarkers and various immune cell types. RESULTS: Our analysis identified ACSS2, LPIN1, and NR4A1 as key mitochondria-related biomarkers associated with PCOS. A notable difference was observed in the immune microenvironment between PCOS patients and healthy controls. In particular, LPIN1 exhibited a positive correlation with resting mast cells, whereas NR4A1 demonstrated a negative correlation with monocytes in PCOS patients. CONCLUSION: ACSS2, LPIN1, and NR4A1 emerge as PCOS-related diagnostic biomarkers and potential intervention targets, opening new avenues for the diagnosis and management of PCOS.

Visible Light-Induced 1,2-Diphenyldisulfane-Mediated Defluoroborylation of Polyfluoroarenes.

A green and practical protocol of defluoroborylation of polyfluoroarenes with stable and readily accessible NHC-borane was developed, using 1,2-diphenyldisulfane as a hydrogen atom transfer (HAT) and single electron transfer (SET) reagent precursor under visible-light irradiation, leading to the concise formation of value-added fluorinated organoboron scaffolds. Mechanism studies revealed the method underwent a boryl radical addition reaction with polyfluoroarene, followed by successive single electron transfer pathways and defluorination of the C-F bond to offer the targeted product. This unprecedented platform relies on 1,2-diphenyldisulfane and base without using expensive photocatalysts, highlighting the methodology has promising application value to prepare borylated polyfluoroarene compounds.

1 H-NMR revealed pyruvate as a differentially abundant metabolite in the venom glands of Apis cerana and Apis mellifera.

As a common defense mechanism in Hymenoptera, bee venom has complex components. Systematic and comprehensive analysis of bee venom components can aid in early evaluation, accurate diagnosis, and protection of organ function in humans in cases of bee stings. To determine the differences in bee venom composition and metabolic pathways between Apis cerana and Apis mellifera, proton nuclear magnetic resonance (1 H-NMR) technology was used to detect the metabolites in venom samples. A total of 74 metabolites were identified and structurally analyzed in the venom of A. cerana and A. mellifera. Differences in the composition and abundance of major components of bee venom from A. cerana and A. mellifera were mapped to four main metabolic pathways: valine, leucine and isoleucine biosynthesis; glycine, serine and threonine metabolism; alanine, aspartate and glutamate metabolism; and the tricarboxylic acid cycle. These findings indicated that the synthesis and metabolic activities of proteins or polypeptides in bee venom glands were different between A. cerana and A. mellifera. Pyruvate was highly activated in 3 selected metabolic pathways in A. mellifera, being much more dominant in A. mellifera venom than in A. cerana venom. These findings indicated that pyruvate in bee venom glands is involved in various life activities, such as biosynthesis and energy metabolism, by acting as a precursor substance or intermediate product.

Association between triglyceride-glucose index and intracranial/extracranial atherosclerotic stenosis: findings from a retrospective study.

OBJECTIVE: The association of the triglyceride-glucose (TyG) index with intracranial atherosclerotic stenosis (ICAS) and extracranial atherosclerotic stenosis (ECAS) is unclear. This study aimed to investigate the relationship of TyG index with the distribution and severity of ICAS and ECAS. METHOD: Patients who underwent digital subtraction angiography (DSA) for evaluating ICAS/ECAS in Zhongnan Hospital of Wuhan University from January 2017 to October 2021 were retrospectively enrolled in our study. Clinical characteristics, DSA data, blood routine, lipid profile and fasting glucose were recorded. The association of TyG index and ICAS/ECAS status were investigated in four aspects: location and distribution of stenosis, stenosis severity and whether stenosis is symptomatic. Logistic regression models were used to evaluate the association. Restricted cubic splines were constructed to model the non-linear relationship between the TyG index and different arterial stenosis status. RESULTS: Among 1129 included patients, the median age was 62 (IQR 55-68) years, and 71.3% were male. The median TyG index was 8.81 (8.40, 9.21). Elevated TyG index was significantly associated with ICAS, combined ICAS/ECAS, anterior circulation stenosis, posterior circulation stenosis, combined anterior/posterior circulation stenosis, severe stenosis, both asymptomatic and symptomatic stenosis. This association was maintained after adjusting for age, sex, smoking, drinking, medical history of hypertension and stroke, platelet, total cholesterol, high-density lipoprotein, and low-density lipoprotein. Multivariable-adjusted spline regression models showed that a progressively increasing risk of arterial stenosis was related to an elevated TyG index. CONCLUSION: Elevated TyG index was associated with ICAS/ECAS. TyG index might be a useful indicator of ICAS and severe stenosis.

Characterization of a membrane Fcγ receptor in largemouth bass (Micropterus saloumoides) and its response to bacterial challenge.

Fc receptors (FcRs), specific to the Fc portion of immunoglobulin (Ig), are required to regulate immune responses against pathogenic infections. However, FcγR is a member of FcRs family, whose structure and function remains to be elucidated in teleost fish. In this study, the FcγRII, from largemouth bass (Micropterus saloumoides), named membrane MsFcγRII (mMsFcγRII), was cloned and identified. The opening reading frame (ORF) of mMsFcγRII was 750 bp, encoding 249 amino acids with a predicted molecular mass of 27 kDa. The mMsFcγRII contained a signal peptide, two Ig domains, a transmembrane domain, and an intracellular region, which was highly homology with FcγR from other teleost fish. The mRNA expression analysis showed that mMsFcγRII was widely distributed in all tested tissues and with the highest expression level in spleen. After bacterial challenge, the expression of mMsFcγRII was significantly upregulated in vivo (spleen and head kidney), as well as in vitro (leukocytes from head kidney). The subcellular localization assay revealed that mMsFcγRII was mostly observed on the membrane of HEK293T cells which were transfected with mMsFcγRII overexpression plasmid. Flow cytometric analysis showed that natural mMsFcγRII protein was highly expressed in head kidney lymphocytes. Moreover, indirect immunofluorescence assay and pull-down assay indicated that mMsFcγRII could bind to IgM purified from largemouth bass serum. These results suggested that mMsFcγRII was likely to play an influential role in the immune response against pathogens and provided valuable insights for studying the function of FcRs in teleost.

A Drosophila Model Reveals the Potential Role for mtt in Retinal Disease.

Congenital stationary night blindness (CSNB) is a genetically heterogeneous inherited retinal disorder, caused by over 300 mutations in 17 different genes. While there are numerous fly models available for simulating ocular diseases, most are focused on mimicking retinitis pigmentosa (RP), with animal models specifically addressing CSNB limited to mammals. Here, we present a CSNB fly model associated with the mtt gene, utilizing RNA interference (RNAi) to silence the mtt gene in fly eyes (homologous to the mammalian GRM6 gene) and construct a CSNB model. Through this approach, we observed significant defects in the eye structure and function upon reducing mtt expression in fly eyes. This manifested as disruptions in the compound eye lens structure and reduced sensitivity to light responses. These results suggest a critical role for mtt in the function of fly adult eyes. Interestingly, we found that the mtt gene is not expressed in the photoreceptor neurons of adult flies but is localized to the inner lamina neurons. In summary, these results underscore the crucial involvement of mtt in fly retinal function, providing a framework for understanding the pathogenic mechanisms of CSNB and facilitating research into potential therapeutic interventions.