IRE1α Mediates the Hypertrophic Growth of Cardiomyocytes Through Facilitating the Formation of Initiation Complex to Promote the Translation of TOP-Motif Transcripts.

BACKGROUND: Cardiomyocyte growth is coupled with active protein synthesis, which is one of the basic biological processes in living cells. However, it is unclear whether the unfolded protein response transducers and effectors directly take part in the control of protein synthesis. The connection between critical functions of the unfolded protein response in cellular physiology and requirements of multiple processes for cell growth prompted us to investigate the role of the unfolded protein response in cell growth and underlying molecular mechanisms. METHODS: Cardiomyocyte-specific inositol-requiring enzyme 1α (IRE1α) knockout and overexpression mouse models were generated to explore its function in vivo. Neonatal rat ventricular myocytes were isolated and cultured to evaluate the role of IRE1α in cardiomyocyte growth in vitro. Mass spectrometry was conducted to identify novel interacting proteins of IRE1α. Ribosome sequencing and polysome profiling were performed to determine the molecular basis for the function of IRE1α in translational control. RESULTS: We show that IRE1α is required for cell growth in neonatal rat ventricular myocytes under prohypertrophy treatment and in HEK293 cells in response to serum stimulation. At the molecular level, IRE1α directly interacts with eIF4G and eIF3, 2 critical components of the translation initiation complex. We demonstrate that IRE1α facilitates the formation of the translation initiation complex around the endoplasmic reticulum and preferentially initiates the translation of transcripts with 5' terminal oligopyrimidine motifs. We then reveal that IRE1α plays an important role in determining the selectivity and translation of these transcripts. We next show that IRE1α stimulates the translation of epidermal growth factor receptor through an unannotated terminal oligopyrimidine motif in its 5' untranslated region. We further demonstrate a physiological role of IRE1α-governed protein translation by showing that IRE1α is essential for cardiomyocyte growth and cardiac functional maintenance under hemodynamic stress in vivo. CONCLUSIONS: These studies suggest a noncanonical, essential role of IRE1α in orchestrating protein synthesis, which may have important implications in cardiac hypertrophy in response to pressure overload and general cell growth under other physiological and pathological conditions.

Silicon and selenium alleviate cadmium toxicity in Artemisia selengensis Turcz by regulating the plant-rhizosphere.

Soil cadmium (Cd) pollution has emerged as a pressing concern due to its deleterious impacts on both plant physiology and human well-being. Silicon (Si) is renowned for its ability to mitigate excessive Cd accumulation within plant cells and reduce the mobility of Cd in soil, whereas Selenium (Se) augments plant antioxidant capabilities and promotes rhizosphere microbial activity. However, research focusing on the simultaneous utilization of Si and Se to ameliorate plant Cd toxicity through multiple mechanisms within the plant-rhizosphere remains comparatively limited. This study combined hydroponic and pot experiments to investigate the effects of the combined application of Si and Se on Cd absorption and accumulation, as well as the growth and rhizosphere of A. selengensis Turcz under Cd stress. The results revealed that a strong synergistic effect was observed between both Si and Se. The combination of Si and Se significantly increased the activity and content of enzymes and non-enzyme antioxidants within A. selengensis Turcz, reduced Cd accumulation and inhibiting its translocation from roots to shoots. Moreover, Si and Se application improved the levels of reducing sugar, soluble protein, and vitamin C, while reducing nitrite content and Cd bioavailability. Furthermore, the experimental results showed that the combination of Si and Se not only increased the abundance of core rhizosphere microorganisms, but also stimulated the activity of soil enzymes, which effectively limited the migration of Cd in the soil. These findings provided valuable insights into the effective mitigation of soil Cd toxicity to plants and also the potential applications in improving plant quality and safety.

A meta-analysis of UCA1 accuracy in the detection of bladder cancer.

INTRODUCTION: Bladder cancer (BCa) exhibits a relatively high prevalence, yet convenient tools for its early detection are lacking. Our study aims to assess the diagnostic value of Urothelial Carcinoma-Associated 1 (UCA1) in the early detection of BCa. METHODS: Systematic searches were performed in electronic databases (PubMed, Web of Science, Science Direct, CNKI, Wanfang, and VIP) until 20 July 2023. QUADAS-2 was used for quality assessment, while Meta-DiSc 1.4 and STATA 14.0 were employed for statistical analysis. RESULTS: A total of 1252 BCa patients and 779 controls, from 12 identified articles, were included. UCA1 showed strong discriminatory ability in BCa detection, with an overall sensitivity of 0.84 specificity of 0.91, and a 0.91 area under the curve (AUC). Strikingly, UCA1 expressed in urine and tissue exhibited higher diagnostic value (0.92 AUC) compared to that in blood (0.86 AUC). Furthermore, urine UCA1 demonstrated remarkable diagnostic performance with 91% sensitivity and 98% specificity. Deeks' funnel plot detected no substantial publication bias. CONCLUSION: UCA1 could serve as a potential biomarker for BCa detection with good diagnostic performance. Besides, compared to UCA1 in blood, urine and tissue UCA1 exhibited higher diagnostic value. Further prospective clinical research is needed to corroborate the conclusion. PROSPERO REGISTRATION: CRD42023463210.

A review of cellulose-based catechol-containing functional materials for advanced applications.

With the increment in global energy consumption and severe environmental pollution, it is urgently needed to explore green and sustainable materials. Inspired by nature, catechol groups in mussel adhesion proteins have been successively understood and utilized as novel biomimetic materials. In parallel, cellulose presents a wide class of functional materials rating from macro-scale to nano-scale components. The cross-over among both research fields alters the introduction of impressive materials with potential engineering properties, where catechol-containing materials supply a general stage for the functionalization of cellulose or cellulose derivatives. In this review, the role of catechol groups in the modification of cellulose and cellulose derivatives is discussed. A broad variety of advanced applications of cellulose-based catechol-containing materials, including adhesives, hydrogels, aerogels, membranes, textiles, pulp and papermaking, composites, are presented. Furthermore, some critical remaining challenges and opportunities are studied to mount the way toward the rational purpose and applications of cellulose-based catechol-containing materials.

HiHo-AID2: boosting homozygous knock-in efficiency enables robust generation of human auxin-inducible degron cells.

Recent developments in auxin-inducible degron (AID) technology have increased its popularity for chemogenetic control of proteolysis. However, generation of human AID cell lines is challenging, especially in human embryonic stem cells (hESCs). Here, we develop HiHo-AID2, a streamlined procedure for rapid, one-step generation of human cancer and hESC lines with high homozygous degron-tagging efficiency based on an optimized AID2 system and homology-directed repair enhancers. We demonstrate its application for rapid and inducible functional inactivation of twelve endogenous target proteins in five cell lines, including targets with diverse expression levels and functions in hESCs and cells differentiated from hESCs.

Porcine deltacoronavirus enters ST cells by clathrin-mediated endocytosis and does not require Rab5, Rab7, or Rab11.

IMPORTANCE: Porcine deltacoronavirus (PDCoV) is a newly emerged enteric virus threatening pig industries worldwide. Our previous work showed that PDCoV enters porcine kidney (PK-15) cells through a caveolae-dependent pathway, but the entry mechanism for PDCoV into swine testicle (ST) cells remains unclear. Mechanisms of virus entry can be different with different virus isolates and cell types. Here, we determined that PDCoV enters ST cells via clathrin-mediated endocytosis. Additionally, we found that PDCoV entry does not require Rab5, Rab7, or Rab11. These findings provide additional understanding of the entry mechanisms of PDCoV and possible antiviral targets.

Maleic acid and malonic acid reduced the pathogenicity of Sclerotinia sclerotiorum by inhibiting mycelial growth, sclerotia formation and virulence factors.

Sclerotinia sclerotiorum is a necrotrophic plant pathogenic fungus with broad distribution and host range. Bioactive compounds derived from plant extracts have been proven to be effective in controlling S. sclerotiorum. In this study, the mycelial growth of S. sclerotiorum was effectively inhibited by maleic acid, malonic acid, and their combination at a concentration of 2 mg/mL, with respective inhibition rates of 32.5%, 9.98%, and 67.6%. The treatment of detached leaves with the two acids resulted in a decrease in lesion diameters. Interestingly, maleic acid and malonic acid decreased the number of sclerotia while simultaneously increasing their weight. The two acids also disrupted the cell structure of sclerotia, leading to sheet-like electron-thin regions. On a molecular level, maleic acid reduced oxalic acid secretion, upregulated the expression of Ss-Odc2 and downregulated CWDE10, Ss-Bi1 and Ss-Ggt1. Differently, malonic acid downregulated CWDE2 and Ss-Odc1. These findings verified that maleic acid and malonic acid could effectively inhibit S. sclerotiorum, providing promising evidence for the development of an environmentally friendly biocontrol agent.

Se Ameliorates Cd Toxicity in Oilseed rape (Brassica napus L.) Seedlings by Inhibiting Cd Transporter Genes and Maintaining root Plasma Membrane Integrity.

Se (Selenium) has been reported to be an important protective agent to decreases Cd (Cadmium) induced toxic in plants. However, it remains unclear how Se mitigates the uptake of Cd and increased the resistance to Cd toxicity. Hydroponic experiments were arranged to investigate the changes of physiological properties, root cell membrane integrity and Cd-related transporter genes in rape seedlings. Comparison of the biomass between the addition of Se and the absence of Se under Cd exposure showed that the Cd-induced growth inhibition of rape seedlings was alleviated by Se. Cd decreased the photosynthetic rate (Pn), stomatal conductance (Gs) and photosynthetic pigment content including chlorophyll a, chlorophyll b and carotenoid. However, all these parameters were all significantly improved by Se addition. Moreover, exposure to Se resulted in a decrease in Cd concentration in both shoot and root, ranging from 4.28 to 27.2%. Notably, the application of Se at a concentration of 1 µmol L- 1 exhibited the best performance. Furthermore, Se enhanced cell membrane integrity and reduced superoxide anion levels, thereby contributing to the alleviation of cadmium toxicity in plants. More critically, Se decreased the expression levels of root Cd-related transporter genes BnIRT1, BnHMA2 and BnHMA4 under Cd stress, which are responsible for Cd transport and translocation. These results are important to increase crop growth and reduce Cd load in the food chain from metal toxicity management and agronomical point of view.

Characterization, phylogenetic analysis, and pathogenicity of a novel genotype 2 porcine Enterovirus G.

Enterovirus G belongs to the family Picornaviridae and are associated with a variety of animal diseases. We isolated and characterized a novel EV-G2 strain, CHN-SCMY2021, the first genotype 2 strain isolated in China. CHN-SCMY2021 is about 25 nm diameter with morphology typical of picornaviruses and its genome is 7341 nucleotides. Sequence alignment and phylogenetic analysis based on VP1 indicated that this isolate is a genotype 2 strain. The whole genome similarity between CHN-SCMY2021 and other EV-G genotype 2 strains is 78.3-86.4%, the greatest similarity is to EVG/Porcine/JPN/Iba26-506/2014/G2 (LC316792.1). Recombination analysis indicated that CHN-SCMY2021 resulted from recombination between 714,171/CaoLanh_VN (KT265894.2) and LP 54 (AF363455.1). Except for ST cells, CHN-SCMY2021 has a broad spectrum of cellular adaptations, which are susceptible to BHK-21, PK-15, IPEC-J2, LLC-PK and Vero cells. In piglets, CHN-SCMY2021 causes mild diarrhea and thinning of the intestinal wall. The virus was mainly distributed to intestinal tissue but was also found in heart, liver, spleen, lung, kidney, brain, and spinal cord. CHN-SCMY2021 is the first systematically characterized EV-G genotype 2 strain from China, our results enrich the information on the epidemiology, molecular evolution and pathogenicity associated with EV-G.

Reaction mechanism and detecting properties of a novel molecularly imprinted electrochemical sensor for microcystin based on three-dimensional AuNPs@MWCNTs/GQDs.

Microcystins with leucine arginine (MC-LR) is a virulent hepatotoxin, which is commonly present in polluted water with its demethylated derivatives [Dha7] MC-LR. This study reported a low-cost molecularly imprinted polymer network-based electrochemical sensor for detecting MC-LR. The sensor was based on a three-dimensional conductive network composed of multi-walled carbon nanotubes (MWCNTs), graphene quantum dots (GQDs), and gold nanoparticles (AuNPs). The molecularly imprinted polymer was engineered by quantum chemical computation utilizing p-aminothiophenol (p-ATP) and methacrylic acid (MAA) as dual functional monomers and L-arginine as a segment template. The electrochemical reaction mechanism of MC-LR on the sensor was studied for the first time, which is an irreversible electrochemical oxidation reaction involving an electron and two protons, and is controlled by a mixed adsorption-diffusion mechanism. The sensor exhibited a great detection response to MC-LR in the linear range of 0.08-2 µg/L, and the limit of detection (LOD) is 0.0027 µg/L (S/N = 3). In addition, the recoveries of the total amount of MC-LR and [Dha7] MC-LR in the actual sample by the obtained sensor were in the range from 91.4 to 116.7%, which indicated its great potential for environmental detection.

Selenium-mediated Cr(VI) reduction and SeNPs synthesis accelerated Bacillus cereus SES to remediate Cr contamination.

Microbial biotransformation of Cr(VI) is a sustainable approach to reduce Cr(VI) toxicity and remediate Cr(VI) contamination. In this study, Bacillus cereus SES with the capability of reducing both Cr(VI) and Se(IV) was isolated, and the effect of Se supplementation on Cr(VI) reduction by Bacillus cereus SES was investigated. Se(IV) addition enabled 2.6-fold faster Cr(VI) reduction, while B. cereus SES reduced 96.96% Se(IV) and produced more selenium nanoparticles (SeNPs) in the presence of Cr(VI). Co-reduction products of B. cereus SES on Cr(VI) and Se(IV) were SeNPs adsorbed with Cr(III). The relevant mechanisms were further revealed by proteomics. Se(IV) supplementation mediated the synthesis of Cr(VI) reductants and stress-resistant substances, thus enhancing Cr(VI) resistance and promoting Cr(VI) reduction. Meanwhile, high Se(IV) reduction rate was associated with Cr(VI)-induced electron transport processes, and Cr(VI) mediated the up-regulation of flagellar assembly, protein export and ABC transporters pathways to synthesis and export more SeNPs. Furthermore, Se combined with B. cereus SES had the potential to reduce the toxicity of Cr(VI) via reducing the bioavailability of Cr and improving the bioavailability of Se in soil. Results suggested that Se could be an efficient strategy to enhance the remediation of B. cereus SES on Cr contamination.

Porcine Deltacoronavirus (PDCoV) Entry into PK-15 Cells by Caveolae-Mediated Endocytosis.

(1) Background: Porcine deltacoronavirus (PDCoV) is a newly emerged enteric virus affecting pig breeding industries worldwide, and its pathogenic mechanism remains unclear. (2) Methods: In this study, we preliminarily identified the endocytic pathway of PDCoV in PK-15 cells, using six chemical inhibitors (targeting clathrin-mediated endocytosis, caveolae-mediated endocytosis, macropinocytosis pathway and endosomal acidification), overexpression of dominant-negative (DN) mutants to treat PK-15 cells and proteins knockdown. (3) Results: The results revealed that PDCoV entry was not affected after treatment with chlorpromazine (CPZ), 5-(N-ethyl-N-isopropyl) amiloride (EIPA)or ammonium chloride (NH4Cl), indicating that the entry of PDCoV into PK-15 cells were clathrin-, micropinocytosis-, PH-independent endocytosis. Conversely, PDCoV infection was sensitive to nystatin, dynasore and methyl-ß-cyclodextrin (MßCD) with reduced PDCoV internalization, indicating that entry of PDCoV into PK-15 cells was caveolae-mediated endocytosis that required dynamin and cholesterol; indirect immunofluorescence and shRNA interference further validated these results. (4) Conclusions: In conclusion, PDCoV entry into PK-15 cells depends on caveolae-mediated endocytosis, which requires cholesterol and dynamin. Our finding is the first initial identification of the endocytic pathway of PDCoV in PK-15 cells, providing a theoretical basis for an in-depth understanding of the pathogenic mechanism of PDCoV and the design of new antiviral targets.

Seipin localizes at endoplasmic-reticulum-mitochondria contact sites to control mitochondrial calcium import and metabolism in adipocytes.

Deficiency of the endoplasmic reticulum (ER) protein seipin results in generalized lipodystrophy by incompletely understood mechanisms. Here, we report mitochondrial abnormalities in seipin-deficient patient cells. A subset of seipin is enriched at ER-mitochondria contact sites (MAMs) in human and mouse cells and localizes in the vicinity of calcium regulators SERCA2, IP3R, and VDAC. Seipin association with MAM calcium regulators is stimulated by fasting-like stimuli, while seipin association with lipid droplets is promoted by lipid loading. Acute seipin removal does not alter ER calcium stores but leads to defective mitochondrial calcium import accompanied by a widespread reduction in Krebs cycle metabolites and ATP levels. In mice, inducible seipin deletion leads to mitochondrial dysfunctions preceding the development of metabolic complications. Together, these data suggest that seipin controls mitochondrial energy metabolism by regulating mitochondrial calcium influx at MAMs. In seipin-deficient adipose tissue, reduced ATP production compromises adipocyte properties, contributing to lipodystrophy pathogenesis.

Study of the inhibitory effect of STAT1 on PDCoV infection.

Porcine deltacoronavirus (PDCoV) is an enteropathogen found in many pig producing countries. It can cause acute diarrhea, vomiting, dehydration, and death in newborn piglets, seriously affecting the development of pig breeding industries. To date, our knowledge of the pathogenesis of PDCoV and its interactions with host cell factors remains incomplete. Using Co-IP coupled with LC/MS-MS, we identified 67 proteins that potentially interact with PDCoV in LLC-PK1 cells; five of the identified proteins were chosen for further evaluation (IMMT, STAT1, XPO5, PIK3AP1, and TMPRSS11E). Five LLC-PK1 cell lines, each with one of the genes of interest knocked down, were constructed using CRISPR/cas9. In these knockdown cells lines, only STAT1KD resulted in a significantly greater virus yield. Knockdown of the remaining four genes resulted, to varying degrees, in a lower virus yield that wild-type LLC-PK1 cells. The absence of STAT1 did not significantly affect the attachment of PDCoV to cells, but did result in increased viral internalization. Additionally, PDCoV infection stimulated expression of interferon stimulated genes (ISGs) downstream of STAT1 (IFIT1, IFIT2, RADS2, ISG15, MX1, and OAS1) while knockdown of STAT1 resulted in a greater than 80 % decrease in the expression of all six ISGs. Our findings show that STAT1 interacts with PDCoV, and plays a negative regulatory role in PDCoV infection.

HSP90 inhibitors 17-AAG and VER-82576 inhibit porcine deltacoronavirus replication in vitro.

Porcine deltacoronavirus (PDCoV) is highly pathogenic to piglets, and no specific drugs or vaccines are available for the prevention and treatment of PDCoV infection, the need for antiviral therapies is pressing. HSP90 inhibitors have potent inhibitory effects against the replication of numerous viruses, hence we evaluated three HSP90 inhibitors, 17-AAG, VER-82576, and KW-2478, for their effects on PDCoV infection in vitro. We evaluated their effectivenesses at suppressing PDCoV by qRT-PCR, western blot, and TCID50 assay, and found that 17-AAG and VER-82576 inhibited PDCoV at the early stage of replication, while KW-2478 showed no significant antiviral activity at any stage of infection. These results indicated that the PDCoV-inhibitory effects of 17-AAG and VER-82576 might be exerted by targeting host cell factor HSP90AB1 but not HSP90AA1. Further study showed that HSP90AB1 mRNA and protein levels were not significantly different in 17-AAG and VER-82576-treated cells versus control cells. 17-AAG and VER-82576 were also evaluated for their effects on the expressions of TNF-α, IL-6, and IL-12, which are PDCoV-induced proinflammatory cytokines. We found that both 17-AAG and VER-82576 inhibited the expressions of TNF-α, IL-6, and IL-12 to varying degrees, but in a dose dependent manner. From our data we can conclude that the HSP90 inhibitors 17-AAG and VER-82576 are promising candidates for the treatment of PDCoV infection.

Specific subdomain localization of ER resident proteins and membrane contact sites resolved by electron microscopy.

The endoplasmic reticulum (ER) is a large, single-copy, membrane-bound organelle that comprises an elaborate 3D network of diverse structural subdomains, including highly curved tubules, flat sheets, and parts that form contacts with nearly every other organelle. The dynamic and complex organization of the ER poses a major challenge on understanding how its functioning - maintenance of the structure, distribution of its functions and communication with other organelles - is orchestrated. In this study, we resolved a unique localization profile within the ER network for several resident ER proteins representing a broad range of functions associated with the ER using immuno-electron microscopy and calculation of a relative labeling index (RLI). Our results demonstrated the effect of changing cellular environment on protein localization and highlighted the importance of correct protein expression level when analyzing its localization at subdomain resolution. We present new software tools for anonymization of images for blind analysis and for quantitative assessment of membrane contact sites (MCSs) from thin section transmission electron microscopy micrographs. The analysis of ER-mitochondria contacts suggested the presence of at least three different types of MCSs that responded differently to changes in cellular lipid loading status.

Process optimization of polyphenol oxidase immobilization: Isotherm, kinetic, thermodynamic and removal of phenolic compounds.

Chitosan/montmorillonite (CTS/MMT) and chitosan­gold nanoparticles/montmorillonite (CTS-Au/MMT) composites were prepared, characterized through Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM), and utilized as support for immobilization of polyphenol oxidase (PPO). PPO was immobilized on CTS/MMT (IPPO) and CTS-Au/MMT (IPPO-Au) by physical adsorption, respectively. In order to achieve simultaneous maximization of immobilization efficiency and enzyme activity, the immobilization process parameters were optimized by Taguchi-Grey relational analysis (TGRA) approach. Under the optimal immobilization condition, the immobilization efficiency and enzyme activity reached at 50.16% and 1.46 × 104 U/mg for IPPO, and 63.35% and 3.01 × 104 U/mg for IPPO-Au, respectively. The isotherm, kinetic and thermodynamics of PPO adsorption were investigated in detail. The adsorption process was better explained by Toth isotherm and Fractal-like pseudo second order model, respectively. Intra-particle diffusion and film diffusion were involved in the adsorption process and intra-particle diffusion was not the only rate-controlling step. The adsorption of PPO was exothermic, physical and spontaneous at the investigated temperature range. The immobilized PPO were used to oxidize phenolic compounds. All investigated phenolic compounds showed the higher conversion as catalyzed by IPPO-Au. For both IPPO and IPPO-Au, the conversion of substituted phenols was higher than that of phenol.

Acute ST-Segment Elevation Myocardial Infarction as Initial Presentation of Atypical Hemolytic-Uremic Syndrome.

A young woman presented with an acute ST-segment elevation myocardial infarction. Her clinical course was complicated by cardiogenic shock and acute renal failure. Work-up revealed thrombocytopenia and hemolytic anemia. A diagnosis of atypical hemolytic-uremic syndrome was made on the basis of clinical and pathological findings. (Level of Difficulty: Intermediate.).