Comparing the obesogenic effect and regulatory mechanisms of long-term exposure to per/polyfluoroalkyl substances with different terminal groups in Caenorhabditis elegans.

Per/polyfluoroalkyl substances (PFASs) are ubiquitous, bioaccumulative, and recalcitrant contaminants, posing global exposure and health risks. The effects of chemical structures on toxicities and the mechanisms of their obesogenic effects were largely unclear. This study used the model organism Caenorhabditis elegans to assess the impact of long-term exposure to different PFASs (PFNA, PFOSA, PFBS, PFHxS, 6:2 FTS, 4:2 FTS, PFOA, and PFOS) on growth and lipid metabolism and discussed the obesogenic mechanisms of selected PFASs. The growth assays indicated longer carbon-fluorine (-CF) chains and total fluorine atoms increased developmental toxicity of PFASs, while at 8 -CF chain-length, PFNA (-COOH terminal), PFOS (-SO3 terminal), and PFOSA (-SO2NH2 terminal) exhibited differential growth inhibition. With the toxicity ranking of PFNA > PFOS > PFOSA, all PFASs significantly induced total lipid accumulation and perturbed the lipid composition in C. elegans. All three PFASs significantly induced lipogenesis gene expression and partially suppressed lipolysis genes. The results suggested that the disruption of lipid metabolism of PFOSA depends on sbp-1, while PFNA and PFOS depend on nhr-49. In conclusion, long-term exposure to PFNA, PFOSA, and PFOS triggers obesogenic effects in organisms by distinct molecular mechanisms.

Identification and Characterization of a Highly Active Hyaluronan Lyase from Enterobacter asburiae.

Hyaluronic acid (HA) is a well-known functional marine polysaccharide. The utilization and derivative development of HA are of great interest. Hyaluronan lyase has wide application prospects in the production of HA oligosaccharides and lower molecular weight HA. In this study, a strain of Enterobacter asburiae CGJ001 with high hyaluronan lyase activity was screened from industrial wastewater. This strain exhibited an impressive enzyme activity of 40,576 U/mL after being incubated for 14 h. Whole genome sequencing analysis revealed that E. asburiae CGJ001 contained a cluster of genes involved in HA degradation, transport, and metabolism. A newly identified enzyme responsible for glycosaminoglycan degradation was designated as HylEP0006. A strain of E. coli BL21(DE3)/pET-22b(+)-hylEP0006 was successfully constructed. HylEP0006 exhibited optimal degradation at 40 °C and pH 7.0, showing a high activity of 950,168.3 U/mg. HylEP0006 showed specific activity against HA. The minimum degradation fragment of HylEP0006 was hyaluronan tetrasaccharides, and HylEP0006 could efficiently degrade HA into unsaturated disaccharides (HA2), with HA2 as the final product. These characteristics indicate that HylEP0006 has a potential application prospect for the extraction and utilization of hyaluronic acid.

Unraveling the intricacies of glycosaminoglycan biosynthesis: Decoding the molecular symphony in understanding complex polysaccharide assembly.

Glycosaminoglycans (GAGs) are extensively utilized in clinical, cosmetic, and healthcare field, as well as in the treatment of thrombosis, osteoarthritis, rheumatism, and cancer. The biological production of GAGs is a strategy that has garnered significant attention due to its numerous advantages over traditional preparation methods. In this review, we embark on a journey to decode the intricate molecular symphony that orchestrates the biosynthesis of glycosaminoglycans. By unraveling the complex interplay of related enzymes and thorough excavation of the intricate metabolic cascades involved, GAGs chain aggregation and transportation, which efficiently and controllably modulate GAGs sulfation patterns involved in biosynthetic pathway, we endeavor to offer a thorough comprehension of how these remarkable GAGs are intricately assembled and pushes the boundaries of our understanding in GAGs biosynthesis.

Targeting tumor cell-to-macrophage communication by blocking Vtn-C1qbp interaction inhibits tumor progression via enhancing macrophage phagocytosis.

Background: Cancer cells are capable of evading clearance by macrophages through overexpression of anti-phagocytic surface proteins known as "don't eat me" signals. Monoclonal antibodies that antagonize the "don't-eat-me" signaling in macrophages and tumor cells by targeting phagocytic checkpoints have shown therapeutic promises in several cancer types. However, studies on the responses to these drugs have revealed the existence of other unknown "don't eat me" signals. Moreover, identification of key molecules and interactions regulating macrophage phagocytosis is required for tumor therapy. Methods: CRISPR screen was used to identify genes that impede macrophage phagocytosis. To explore the function of Vtn and C1qbp in phagocytosis, knockdown and subsequent functional experiments were conducted. Flow cytometry were performed to explore the phagocytosis rate, polarization of macrophage, and immune microenvironment of mouse tumor. To explore the underlying molecular mechanisms, RNA sequencing, immunoprecipitation, mass spectrometry, and immunofluorescence were conducted. Then, in vivo experiments in mouse models were conducted to explore the probability of Vtn knockdown combined with anti-CD47 therapy in breast cancer. Single-cell sequencing data from the Gene Expression Omnibus from The Cancer Genome Atlas database were analyzed. Results: We performed a genome-wide CRISPR screen to identify genes that impede macrophage phagocytosis, followed by analysis of cell-to-cell interaction databases. We identified a ligand-receptor pair of Vitronectin (Vtn) and complement C1Q binding protein (C1qbp) in tumor cells or macrophages, respectively. We demonstrated tumor cell-secreted Vtn interacts with C1qbp localized on the cell surface of tumor-associated macrophages, inhibiting phagocytosis of tumor cells and shifting macrophages towards the M2-like subtype in the tumor microenvironment. Mechanistically, the Vtn-C1qbp axis facilitated FcγRIIIA/CD16-induced Shp1 recruitment, which reduced the phosphorylation of Syk. Furthermore, the combination of Vtn knockdown and anti-CD47 antibody effectively enhanced phagocytosis and infiltration of macrophages, resulting in a reduction of tumor growth in vivo. Conclusions: This work has revealed that the Vtn-C1qbp axis is a new anti-phagocytic signal in tumors, and targeting Vtn and its interaction with C1qbp may sensitize cancer to immunotherapy, providing a new molecular target for the treatment of triple-negative breast cancer.

Electride pureα-Zr: interstitial electrons induced type-II nodal line.

Electrides have attracted significant attention in the fields of physics, materials science, and chemistry due to their distinctive electron properties characterized by weak nuclear binding. In this study, based on first-principles calculations and symmetry analysis, we report that the pure zirconium with alpha-phase (α-Zr) is expected to be the electrically neutral electride with topological nodal loop. Furthermore, the nodal loop located at thekz= 0 plane exhibits a clear drumhead-like surface state. The energy levels of the topological nodal loop can be regulated by applying uniaxial strain, resulting in the topological nodal loop being closer to the Fermi level. Remarkably, the work function of the electride Zr shows a significant anisotropy along the (001), (100), and (110) directions, particularly with a low work function of 3.14 eV along the (110) surface. Therefore, we predict thatα-Zr provides a promising platform for future research on topological electrides.

KINASE-INDUCIBLE DOMAIN INTERACTING 8 regulates helical pod morphology in Medicago truncatula.

Leguminosae exhibits a wide diversity of legume forms with varying degrees of spiral morphologies, serving as an ideal clade for studying the growth and development of spiral organs. While soybean (Glycine max) develops straight pods, the pod of the model legume Medicago truncatula is a helix structure. Despite the fascinating structures and intensive description of the pods in legumes, little is known regarding the genetic mechanism underlying the highly varied spirality of the legume pods. In this study, we found that KINASE-INDUCIBLE DOMAIN INTERACTING 8 (MtKIX8) plays a key role in regulating the pod structure and spirality in M. truncatula. Unlike the coiled and barrel-shaped helix pods of the wild type, the pods of the mtkix8 mutant are loose and deformed and lose the topologic structure as observed in the wild-type pods. In the pods of the mtkix8 mutant, the cells proliferate more actively and overly expand, particularly in the ventral suture, resulting in uncoordinated growth along the dorsal and ventral sutures of pods. The core cell cycle genes CYCLIN D3s are upregulated in the mtkix8 pods, leading to the prolonged growth of the ventral suture region of the pods. Our study revealed the key role of MtKIX8 in regulating seed pod development in M. truncatula and demonstrates a genetic regulatory model underlying the establishment of the helical pod in legumes.

Targeting carnitine palmitoyl transferase 1A (CPT1A) induces ferroptosis and synergizes with immunotherapy in lung cancer.

Despite the successful application of immune checkpoint therapy, no response or recurrence is typical in lung cancer. Cancer stem cells (CSCs) have been identified as a crucial player in immunotherapy-related resistance. Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, is highly regulated by cellular metabolism remolding and has been shown to have synergistic effects when combined with immunotherapy. Metabolic adaption of CSCs drives tumor resistance, yet the mechanisms of their ferroptosis defense in tumor immune evasion remain elusive. Here, through metabolomics, transcriptomics, a lung epithelial-specific Cpt1a-knockout mouse model, and clinical analysis, we demonstrate that CPT1A, a key rate-limiting enzyme of fatty acid oxidation, acts with L-carnitine, derived from tumor-associated macrophages to drive ferroptosis-resistance and CD8+ T cells inactivation in lung cancer. Mechanistically, CPT1A restrains ubiquitination and degradation of c-Myc, while c-Myc transcriptionally activates CPT1A expression. The CPT1A/c-Myc positive feedback loop further enhances the cellular antioxidant capacity by activating the NRF2/GPX4 system and reduces the amount of phospholipid polyunsaturated fatty acids through ACSL4 downregulating, thereby suppressing ferroptosis in CSCs. Significantly, targeting CPT1A enhances immune checkpoint blockade-induced anti-tumor immunity and tumoral ferroptosis in tumor-bearing mice. The results illustrate the potential of a mechanism-guided therapeutic strategy by targeting a metabolic vulnerability in the ferroptosis of CSCs to improve the efficacy of lung cancer immunotherapy.

Two-dimensional Cs3Sb2Br9 inducing transformation of three-dimensional CsPbBr3 to nanoplates.

This communication describes an effective morphological control strategy involving introducing two-dimensional (2D) Cs3Sb2Br9 to induce a transformation of three-dimensional (3D) CsPbBr3 to 2D nanoplates (NPLs). By tuning the Sb/Pb ratio, 2D CsPbBr3 NPLs exhibiting a deep-blue emission centered at a wavelength of 464 nm with an FWHM of 24 nm have been produced. The absence of organic ligands in these high-quality 2D NPLs mitigate the instability issue induced by organic ligand migration and penetration, and these NPLs exhibit 80% of the initial PL intensity after 55 days.

High-Level Extracellular Expression of Hyaluronate Lyase HylP in Bacillus subtilis for Hyaluronan Degradation.

Hyaluronate lyase (HA lyase) has potential in the industrial processing of hyaluronan. In this study, HylP, an HA lyase from Streptococcus pyogenes phage (SPB) was successfully expressed in Bacillus subtilis. To improve the extracellular enzyme activity of HylP in B. subtilis, signal peptide engineering systematic optimization was carried out, and cultured it from shake flasks and fermenters, followed by purification, characterization, and analysis of degradation products. The results showed that the replacement of the signal peptide increased the extracellular enzyme activity of HylP from 1.0 × 104 U/mL to 1.86 × 104 U/mL in the shake flask assay, and using a 20 L fermenter in a batch fermentation process, the extracellular enzyme activity achieved the level of 1.07 × 105 U/mL. HylP exhibited significant thermal and pH stability in the temperature range of 40 °C and pH range of 4-8, respectively. The enzyme showed optimum activity at 40 °C and pH 6, with significant activity in the presence of Na+, Mg2+, and Co2+ ions. Degradation analysis showed that HylP efficiently degraded hyaluronan as an endonuclease, releasing unsaturated disaccharides. These comprehensive findings underscore the substantial industrial potential of HylP for hyaluronan processing applications, offering valuable insights into enzyme characterization and optimization of expression for potential industrial utilization.

Engineering protein translocation and unfolded protein response enhanced human PH-20 secretion in Pichia pastoris.

Hyaluronidases catalyze the degradation of hyaluronan (HA), which is finding rising applications in medicine, cosmetic, and food industries. Recombinant expression of hyaluronidases in microbial hosts has been given special attention as a sustainable way to substitute animal tissue-derived hyaluronidases. In this study, we focused on optimizing the secretion of hyaluronidase from Homo sapiens in Pichia pastoris by secretion pathway engineering. The recombinant hyaluronidase was first expressed under the control of a constitutive promoter PGCW14. Then, two endoplasmic reticulum-related secretory pathways were engineered to improve the secretion capability of the recombinant strain. Signal peptide optimization suggested redirecting the protein into co-translational translocation using the ost1-proα signal sequence improved the secretion level by 20%. Enhancing the co-translational translocation by overexpressing signal recognition particle components further enhanced the secretory capability by 48%. Then, activating the unfolded protein response by overexpressing a transcriptional factor ScHac1p led to a secreted hyaluronidase activity of 4.06 U/mL, which was 2.1-fold higher than the original strain. Finally, fed-batch fermentation elevated the production to 19.82 U/mL. The combined engineering strategy described here could be applied to enhance the secretion capability of other proteins in yeast hosts. KEY POINTS: • Improving protein secretion by enhancing co-translational translocation in P. pastoris was reported for the first time. • Overexpressing Hac1p homologous from different origins improved the rhPH-20 secretion. • A 4.9-fold increase in rhPH-20 secretion was achieved after fermentation optimization and fed-batch fermentation.

Pan-cancer analysis of the tumorigenic role of Fanconi anemia complementation group D2 (FANCD2) in human tumors.

Monoubiquitination of FANCD2 is a central step in the activation of the Fanconi anemia (FA) pathway after DNA damage. Defects in the FA pathway centered around FANCD2 not only lead to genomic instability but also induce tumorigenesis. At present, few studies have investigated FANCD2 in tumors, and no pan-cancer research on FANCD2 has been conducted. We conducted a comprehensive analysis of the role of FANCD2 in cancer using public databases and other published studies. Moreover, we evaluated the role of FANCD2 in the proliferation, migration and invasion of lung adenocarcinoma cells through in vitro and in vivo experiments, and explored the role of FANCD2 in cisplatin chemoresistance. We investigated the regulatory effect of FANCD2 on the cell cycle of lung adenocarcinoma cells by flow cytometry, and verified this effect by western blotting. FANCD2 expression is elevated in most TCGA tumors and shows a strong positive correlation with poor prognosis in tumor patients. In addition, FANCD2 expression shows strong correlations with immune infiltration, immune checkpoints, the tumor mutation burden (TMB), and microsatellite instability (MSI), which are immune-related features, suggesting that it may be a potential target of tumor immunotherapy. We further found that FANCD2 significantly promotes the proliferation, invasion, and migration abilities of lung adenocarcinoma cells and that its ability to promote cancer cell proliferation may be achieved by modulating the cell cycle. The findings indicate that FANCD2 is a potential biomarker and therapeutic target in cancer treatment by analyzing the oncogenic role of FANCD2 in different tumors.

Mutual communication between radiosensitive and radioresistant esophageal cancer cells modulates their radiosensitivity.

Radiotherapy is an important treatment modality for patients with esophageal cancer; however, the response to radiation varies among different tumor subpopulations due to tumor heterogeneity. Cancer cells that survive radiotherapy (i.e., radioresistant) may proliferate, ultimately resulting in cancer relapse. However, the interaction between radiosensitive and radioresistant cancer cells remains to be elucidated. In this study, we found that the mutual communication between radiosensitive and radioresistant esophageal cancer cells modulated their radiosensitivity. Radiosensitive cells secreted more exosomal let-7a and less interleukin-6 (IL-6) than radioresistant cells. Exosomal let-7a secreted by radiosensitive cells increased the radiosensitivity of radioresistant cells, whereas IL-6 secreted by radioresistant cells decreased the radiosensitivity of radiosensitive cells. Although the serum levels of let-7a and IL-6 before radiotherapy did not vary significantly between patients with radioresistant and radiosensitive diseases, radiotherapy induced a more pronounced decrease in serum let-7a levels and a greater increase in serum IL-6 levels in patients with radioresistant cancer compared to those with radiosensitive cancer. The percentage decrease in serum let-7a and the percentage increase in serum IL-6 levels at the early stage of radiotherapy were inversely associated with tumor regression after radiotherapy. Our findings suggest that early changes in serum let-7a and IL-6 levels may be used as a biomarker to predict the response to radiotherapy in patients with esophageal cancer and provide new insights into subsequent treatments.

Overcoming delivery barriers for RNA therapeutics in the treatment of rheumatoid arthritis.

RNA therapeutics can manipulate gene expression or protein production, making them suitable for treating a wide range of diseases. Theoretically, any disease that has a definite biological target would probably find feasible therapeutic approach from RNA-based therapeutics. Numerous clinical trials using RNA therapeutics fighting against cancer, infectious diseases or inherited diseases have been reported and achieved desirable therapeutic efficacy. So far, encouraging findings from various animal experimental studies have also confirmed the great potential of RNA-based therapies in the treatment of rheumatic arthritis (RA). However, the in vivo multiple physiological barriers still seriously compromise the therapeutic efficacy of RNA drugs. Thus, safe and effective delivery strategies for RNA therapeutics are quite essential for their further and wide application in RA therapy. In this review, we will discuss the recent progress achieved using RNA-based therapeutics and focus on delivery strategies that can overcome the in vivo delivery barriers in RA treatment. Furthermore, discussion about the existing problems in current RNA delivery systems for RA therapy has been also included here.

IGF2BP3 Enhances the Growth of Hepatocellular Carcinoma Tumors by Regulating the Properties of Macrophages and CD8+ T Cells in the Tumor Microenvironment.

Background and Aims: Overexpression of IGF2BP3 is associated with the prognosis of hepatocellular carcinoma (HCC). However, its role in regulating tumor immune microenvironment (TME) is not well characterized. Here, we investigated the effects of IGF2BP3 on macrophages and CD8+ T cells within the TME of HCC. Methods: The relationship between IGF2BP3 and immune cell infiltration was analyzed using online bioinformatics tools. Knockout of IGF2BP3 in mouse hepatoma cell line Hepa1-6 was established using CRISPR/Cas9 technology. In vitro cell coculture and subcutaneously implanted hepatoma mice model were used to explore the effects of IGF2BP3 on immune cells. Expression of CCL5 or transforming growth factor beta 1 (TGF-ß1) was detected with quantitative real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The binding of IGF2BP3 and its target RNA was verified by trimolecular fluorescence complementation system and RNA immunoprecipitation followed by quantitative or semiquantitative polymerase chain reaction. Results: IGF2BP3 expression was elevated in HCC and was positively correlated with macrophage infiltration. Patients with higher IGF2BP3 expression and lower macrophage infiltration had a better survival rate. We found that IGF2BP3 could bind to the mRNA of CCL5 or TGF-ß1, increasing their expression, and inducing macrophage infiltration and M2 polarization while inhibiting the activation of CD8+ T cells. Furthermore, inhibition of IGF2BP3 combined with anti-CD47 antibody treatment significantly suppressed the growth of hepatoma in Hepa1-6 xenograft tumor mice. Conclusions: IGF2BP3 promoted the infiltration and M2-polarization of macrophages and suppressed CD8+ T activation by enhancing CCL5 and TGF-ß1 expression, which facilitated the progression of Hepa1-6 xenograft tumor.

Stable deep-blue FAPbBr3 quantum dots facilitated by amorphous metal halide matrices.

This communication describes a strategy to synthesize stable deep blue FAPbBr3 quantum dots (QDs) by constructing a matrix structure. Amorphous Ni2+-based metal halide matrices can stabilize QDs from both chemical and physical factors, and Ni2+ doping can further enhance their structural stability due to lattice shrinking. Such deep blue QD films exhibit stable X-ray diffraction patterns and photoluminescence even after 245 days of storage.

Small cytosolic double-stranded DNA represses cyclic GMP-AMP synthase activation and induces autophagy.

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway is a major mediator of inflammation following stimulation with >45 bp double-stranded DNA (dsDNA). Herein, we identify a class of ∼20-40 bp small cytosolic dsDNA (scDNA) molecules that compete with long dsDNA (200-1,500 bp herring testis [HT]-DNA) for binding to cGAS, thus repressing HT-DNA-induced cGAS activation. The scDNA promotes cGAS and Beclin-1 interaction, releasing Rubicon, a negative regulator of phosphatidylinositol 3-kinase class III (PI3KC3), from the Beclin-1-PI3KC3 complex. This leads to PI3KC3 activation and induces autophagy, causing degradation of STING and long cytosolic dsDNA. Moreover, DNA damage decreases, and autophagy inducers increase scDNA levels. scDNA transfection and treatment with autophagy inducers attenuate DNA damage-induced cGAS activation. Thus, scDNA molecules serve as effective brakes for cGAS activation, preventing excessive inflammatory cytokine production following DNA damage. Our findings may have therapeutic implications for cytosolic DNA-associated inflammatory diseases.

Multidentate Ligand-Passivated CsPbI3 Perovskite Nanocrystals for Stable and Efficient Red-Light-Emitting Diodes.

CsPbI3 nanocrystals (NCs) have become a research hot spot in the field of light-emitting diodes (LEDs). Whereas, the long chain ligands with weak affinity to CsPbI3 NCs have prevented their further development and commercialization. Herein, a novel multidentate short ligand tetramethylthiuram disulfide (TMTD) was employed via a ligand exchange process to enhance hole mobility and decrease trap density of the CsPbI3 NCs film. Therefore, TMTD passivated CsPbI3 NCs LED exhibited 20.65% maximum external quantum efficiency and 3861 cd/m2 maximum luminance. Furthermore, TMTD passivated CsPbI3 NCs LED exhibited good operational stability with a 128 min half-lifetime. This strategy using multidentate short ligand passivation provides an effective way to promote perovskite LED development and commercialization.

Genetic variation reveals the enhanced microbial hyaluronan biosynthesis via atmospheric and room temperature plasma.

This study reveals the genetic and biochemical changes underlying the enhanced hyaluronan (HA) biosynthesis in Streptococcus zooepidemicus. After multiple rounds of atmospheric and room temperature plasma (ARTP) mutagenesis combined with novel bovine serum albumin/cetyltrimethylammonium bromide coupled high-throughput screening assay, the HA yield of the mutant was increased by 42.9% and reached 0.813 g L-1 with a molecular weight of 0.54 × 106 Da within 18 h by shaking flask culture. HA production was increased to 4.56 g L-1 by batch culture in 5-L fermenter. Transcriptome sequencing exhibits that distinct mutants have similar genetic changes. Regulation in direction of metabolic flow into the HA biosynthesis, by enhancing genes responsible for the biosynthesis of HA including hasB, glmU and glmM, weaking downstream gene (nagA and nagB) of UDP-GlcNAc and significantly down-regulating transcription of wall-synthesizing genes, resulting in the accumulation of precursors (UDP-GlcA and UDP-GlcNAc) increased by 39.74% and 119.22%, respectively. These associated regulatory genes may provide control point for engineering of the efficient HA-producing cell factory.

High-level expression and characterization of a highly active hyaluronate lyase HylC with significant potential in hyaluronan oligosaccharide preparation.

Hyaluronate lyases (HA lyases) have been proved to distribute widely among microorganisms, with large potential in hyaluronan processing. Here, a highly active HA lyase HylC from Citrobacter freundii strain Cf1 is reported. HylC was expressed in Escherichia coli BL21(DE3) under the regulation of T7 promoter, and purified to electrophoretic homogeneity for enzymatic characterization, which suggested its suitable thermo- and pH stability under 45 °C and pH rang of 4-8, and high halotolerancy in 1.5 M NaCl. The enzyme exhibited the optimal activity under 37 °C and pH 5.5, and was activated by Ca2+, K+, Zn2+, Ni2+ and Li+. Analysis of degradation product proved it cleave HA in endolytic manner, releasing unsaturated disaccharides as final product. Then, through optimization of promoter and construction of dual promoter, expression level of HylC improved from 1.10 × 104 U/mL to 2.64 × 104 U/mL on shake-flask level. Finally, through batch fermentation, a highest activity of 2.65×105 U/mL was achieved in a 5-L fermenter. Taken together, this work demonstrates the potential of HylC and its recombinant strain in industrial applications. To our knowledge, the HA lyase production reported in this study was the highest level in literatures to date.