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Recently, layered double hydroxides (LDH) have shown great potential in photoreduction of CO2 owing to its flexible structural adjustability. In this study, the mild acidic property of tannic acid (TA) is exploited to etch the bimetal LDH to create abundant vacancies to gain the coordination unsaturated active centers. Based on the different chelating abilities of TA to various metal ions, the active metals are remained by selective chelation while the inert metals are removed during the etching process of bimetal LDH. Furthermore, selective chelating with metal ions not only increases the percentage of highly active metals but also compensates for the structural damage caused by the etch, which achieves a scalpel-like selective construction of vacancies. The NiAl-LDH etched and functionalized by TA for 3 h exhibits superior photo-reduction of CO2 performance without co-catalysts and photo-sensitizers, which is 14 times that of the pristine NiAl-LDH. The fact that many bimetal LDHs can be functionalized by TA and exhibit significantly improved photocatalytic efficiency is confirmed, suggesting this strategy is generalized to functionalize double- or multi-metal LDH. The method provided in this work opens the door for polyphenol-functionalized LDHs to enhance their ability for light-driven chemical transformations.
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Egg performance significantly impacts the development of the local goose industry. The hypothalamus plays an essential role in the egg production of birds. However, few potential candidate genes and biological functions related to egg production in geese have been identified in hypothalamus tissue. In this study, 115 geese were raised and observed for 5 months during the laying period. To understand the regulation mechanism of egg production, the hypothalamus transcriptome profiles of these geese were sequenced using RNA-seq. The hypothalamus samples of four high egg production (HEP) and four low egg production (LEP) geese were selected and collected, respectively. A total of 14,679 genes were identified in the samples. After multiple bioinformatics analyses, Gene Ontology (GO) annotations indicated that genes related to egg production were mainly enriched in biological processes of "response to light stimulus," "sensory system development," and "visual perception." Six potential candidate genes (PDE6C, RHO, MFRP, F2, APOB, and IL6) based on their corresponding GO terms and interaction networks were identified. These identified candidate genes can be used as selection markers to improve the egg production of Wanxi white geese. Our study highlights how visual perception may affect the regulation of geese egg production.
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Sarcosine plays a key role in screening for early prostate cancer. However, the several already reported peroxidase mimics immobilized with sarcosine oxidase (SOX) utilized to detect uriary sarcosine still have some limitations such as complex synthesis process, using of expensive heavy metals to mimic enzyme activity and long color development time. Herein, an inexpensive peroxidase-like 2D Fe/Co-MOF nanosheet was prepared by a simple solvent modulation method. The resultant 2D Fe/Co-MOF nanosheets have strong peroxidase activity, with its Vmax value for H2O2 of 15.3 × 10-8 M/s, being 1.76 times that of HRP. Then, using the 2D Fe/Co-MOF as a peroxidase model for anchoring natural SOX to construct 2D Fe/Co-MOF/SOX , which can act as a cascade reactor for detection of sarcosine. Considering the above properties, a platform for the detection of sarcosine was built based on a colorimetric method. Because of presence of the high ratio of Fe2+ caused by the electron transfer from Co2+ to Fe3+, large specific surface area and plentiful active sites, 2D Fe/Co-MOF/SOX with TMB (3,3',5,5'-tetramethylbenzidine) colorimetric reagent could have fast color development and can be applied conveniently and fastly in an early screening tool for prostate cancer patients. The sarcosine could be quantified by peroxidase activity with a detection range of 1-400 µM and a limit of detection (LOD) of 0.324 µM. More importantly, the average sarcosine concentration of 21.367 µM and 1.871 µM was detected in patient's and normal urine (n = 5), respectively, which showed an excellent screening effect and a great potential in early prostate cancer.
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Bicyclo[1.1.1]pentane (BCP) heteroaryls make up an important class of BCP derivatives in drug discovery. Herein, we report the visible-light-mediated synthesis of cyanoisopropyl BCP-heteroaryls motifs from N-containing heterocycles, [1.1.1]propellane, and AIBN (2,2'-azobis(isobutyronitrile)) through three-component cascade reaction. Importantly, this protocol is compatible with pyrazinones, quinoxaline-2(1H)-one, azauracils, quinoline derivatives, and imidazo[1,2-b]pyridazine, as well as various phenyl disulfide derivatives; thus, this operationally simple and general methodology could enable rapid library generation of sought-after BCP derivatives for drug development.
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The human methyltransferase and transcriptional coactivator MLL4 and its paralog MLL3 are frequently mutated in cancer. MLL4 and MLL3 monomethylate histone H3K4 and contain a set of uncharacterized PHD fingers. Here, we report a novel function of the PHD2 and PHD3 (PHD2/3) fingers of MLL4 and MLL3 that bind to ASXL2, a component of the Polycomb repressive H2AK119 deubiquitinase (PR-DUB) complex. The structure of MLL4 PHD2/3 in complex with the MLL-binding helix (MBH) of ASXL2 and mutational analyses reveal the molecular mechanism which is conserved in homologous ASXL1 and ASXL3. The native interaction of the Trithorax MLL3/4 complexes with the PR-DUB complex in vivo depends solely on MBH of ASXL1/2, coupling the two histone modifying activities. ChIP-seq analysis in embryonic stem cells demonstrates that MBH of ASXL1/2 is required for the deubiquitinase BAP1 recruitment to MLL4-bound active enhancers. Our findings suggest an ASXL1/2-dependent functional link between the MLL3/4 and PR-DUB complexes.
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Proteínas de Ligação a DNA , Histona-Lisina N-Metiltransferase , Ligação Proteica , Proteínas Repressoras , Proteínas Supressoras de Tumor , Ubiquitina Tiolesterase , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Humanos , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Animais , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Camundongos , Elementos Facilitadores Genéticos , Células HEK293 , Dedos de Zinco PHD , Histonas/metabolismoRESUMO
The adsorptive separation of ternary propyne (C3H4)/propylene (C3H6)/propane (C3H8) mixtures is of significant importance due to its energy efficiency. However, achieving this process using an adsorbent has not yet been accomplished. To tackle such a challenge, herein, we present a novel approach of fine-regulation of the gradient of gate-opening in soft nanoporous crystals. Through node substitution, an exclusive gate-opening to C3H4 (17.1 kPa) in NTU-65-FeZr has been tailored into a sequential response of C3H4 (1.6 kPa), C3H6 (19.4 kPa), and finally C3H8 (57.2 kPa) in NTU-65-CoTi, of which the gradient framework changes have been validated by in situ powder X-ray diffractions and modeling calculations. Such a significant breakthrough enables NTU-65-CoTi to sieve the ternary mixtures of C3H4/C3H6/C3H8 under ambient conditions, particularly, highly pure C3H8 (99.9%) and C3H6 (99.5%) can be obtained from the vacuum PSA scheme. In addition, the fully reversible structural change ensures no loss in performance during the cycling dynamic separations. Moving forward, regulating gradient gate-opening can be conveniently extended to other families of soft nanoporous crystals, making it a powerful tool to optimize these materials for more complex applications.
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Human mixed lineage leukemia 4 (MLL4), also known as KMT2D, regulates cell type specific transcriptional programs through enhancer activation. Along with the catalytic methyltransferase domain, MLL4 contains seven less characterized plant homeodomain (PHD) fingers. Here, we report that the sixth PHD finger of MLL4 (MLL4PHD6) binds to the hydrophobic motif of ten-eleven translocation 3 (TET3), a dioxygenase that converts methylated cytosine into oxidized derivatives. The solution NMR structure of the TET3-MLL4PHD6 complex and binding assays show that, like histone H4 tail, TET3 occupies the hydrophobic site of MLL4PHD6, and that this interaction is conserved in the seventh PHD finger of homologous MLL3 (MLL3PHD7). Analysis of genomic localization of endogenous MLL4 and ectopically expressed TET3 in mouse embryonic stem cells reveals a high degree overlap on active enhancers and suggests a potential functional relationship of MLL4 and TET3.
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Proteínas de Ligação a DNA , Dioxigenases , Histona-Lisina N-Metiltransferase , Ligação Proteica , Humanos , Dioxigenases/metabolismo , Dioxigenases/química , Dioxigenases/genética , Animais , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Sítios de Ligação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Modelos Moleculares , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteína de Leucina Linfoide-Mieloide/química , Proteína de Leucina Linfoide-Mieloide/genéticaRESUMO
We report here an asymmetric N,S-coordinated cobalt-based single-atom catalyst with sulfur (S)-bridge ligands (Co-N/S-C) for the oxygen reduction reaction (ORR). The Co-N/S-C exhibits a half-wave potential (E1/2) of 0.908 V versus RHE, outperforming most state-of-the-art ORR catalysts. Theoretical calculations indicate that the CoN3SC10-S moiety facilitates the ORR kinetics by optimizing the adsorption of intermediates. This work provides new insights into the design of single-atom catalysts for electrocatalysis through heteroatom-bridge ligand engineering.
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The discovery of non-precious catalysts for replacing the precious metal of ruthenium in the oxygen evolution reaction (OER) represents a key step in reducing the cost of green hydrogen production. The 2D d-MHOFs, a new 2D materials with controllable oxygen vacancies formed by controlling the degree of coordination bridging between metal hydroxyl oxide and BDC ligands are synthesized at room temperature, exhibit excellent OER properties with low overpotentials of 207 mV at 10 mA cm-2. High-resolution transmission electron microscopy images and density functional theory calculations demonstrate that the introduction of oxygen vacancy sites leads to a lattice distortion and charge redistribution in the catalysts, enhancing the OER activity of 2D d-MHOFs comprehensively. Synchrotron radiation and in situ Raman/Fourier transform infrared spectroscopy indicate that part of oxygen defect sites on the surface of 2D d-MHOFs are prone to transition to highly active metal hydroxyl oxides during the OER process. This work provides a mild strategy for scalable preparation of 2D d-MHOFs nanosheets with controllable oxygen defects, reveals the relationship between oxygen vacancies and OER performance, and offers a profound insight into the basic process of structural transformation in the OER process.
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Chromatin organization is essential for maintaining cell-fate trajectories and developmental programs. Here, we find that disruption of H3K36 methylation dramatically impairs normal epithelial differentiation and development, which promotes increased cellular plasticity and enrichment of alternative cell fates. Specifically, we observe a striking increase in the aberrant generation of excessive epithelial glandular tissues, including hypertrophic salivary, sebaceous, and meibomian glands, as well as enhanced squamous tumorigenesis. These phenotypic and gene expression manifestations are associated with loss of H3K36me2 and rewiring of repressive H3K27me3, changes we also observe in human patients with glandular hyperplasia. Collectively, these results have identified a critical role for H3K36 methylation in both in vivo epithelial cell-fate decisions and the prevention of squamous carcinogenesis and suggest that H3K36 methylation modulation may offer new avenues for the treatment of numerous common disorders driven by altered glandular function, which collectively affect large segments of the human population.
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Carcinoma de Células Escamosas , Histonas , Humanos , Histonas/metabolismo , Plasticidade Celular , Metilação , Carcinogênese/genética , Carcinoma de Células Escamosas/genéticaRESUMO
Histone-lysine N-methyltransferase 2 (KMT2) methyltransferases are critical for gene regulation, cell differentiation, animal development, and human diseases. KMT2 biological roles are often attributed to their methyltransferase activities on lysine 4 of histone H3 (H3K4). However, recent data indicate that KMT2 proteins also possess non-enzymatic functions. In this review, we discuss the current understanding of KMT2 family, with a focus on their enzymatic activity-dependent and -independent functions. Six mammalian KMT2 proteins of three subgroups, KMT2A/B (MLL1/2), KMT2C/D (MLL3/4), and KMT2F/G (SETD1A/B or SET1A/B), have shared and distinct protein domains, catalytic substrates, genomic localizations, and associated complex subunits. Recent studies have revealed the importance of KMT2C/D in enhancer regulation, differentiation, development, tumor suppression and highlighted KMT2C/D enzymatic activity-dependent and -independent roles in mouse embryonic development and cell differentiation. Catalytic dependent and independent functions for KMT2A/B and KMT2F/G in gene regulation, differentiation, and development are less understood. Finally, we provide our perspectives and lay out future research directions that may help advance the investigation on enzymatic activity-dependent and -independent biological roles and working mechanisms of KMT2 methyltransferases.
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Histona-Lisina N-Metiltransferase , Histonas , Animais , Humanos , Camundongos , Diferenciação Celular/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica , Histonas/metabolismo , Domínios Proteicos , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Neoplasias/genéticaRESUMO
Cornelia de Lange syndrome (CdLS) is a congenital disorder featuring facial dysmorphism, postnatal growth deficits, cognitive disability and upper limb abnormalities. CdLS is genetically heterogeneous, with cases arising from mutation of BRD4, a bromodomain protein that binds and reads acetylated histones. In this study, we have modeled CdLS facial pathology through mouse neural crest cell (NCC)-specific mutation of BRD4 to characterize cellular and molecular function in craniofacial development. Mice with BRD4 NCC loss of function died at birth with severe facial hypoplasia, cleft palate, mid-facial clefting and exencephaly. Following migration, BRD4 mutant NCCs initiated RUNX2 expression for differentiation to osteoblast lineages but failed to induce downstream RUNX2 targets required for lineage commitment. BRD4 bound to active enhancers to regulate expression of osteogenic transcription factors and extracellular matrix components integral for bone formation. RUNX2 physically interacts with a C-terminal domain in the long isoform of BRD4 and can co-occupy osteogenic enhancers. This BRD4 association is required for RUNX2 recruitment and appropriate osteoblast differentiation. We conclude that BRD4 controls facial bone development through osteoblast enhancer regulation of the RUNX2 transcriptional program.
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Síndrome de Cornélia de Lange , Fatores de Transcrição , Animais , Camundongos , Proteínas de Ciclo Celular/genética , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core , Síndrome de Cornélia de Lange/genética , Crista Neural/metabolismo , Proteínas Nucleares/metabolismo , Osteoblastos/metabolismo , Osteogênese , Fatores de Transcrição/metabolismoRESUMO
Osteoarthritis (OA) is one of the most common joint diseases, there are no effective disease-modifying drugs, and the pathological mechanisms of OA need further investigation. Here, we show that H3K36 methylations were decreased in senescent chondrocytes and age-related osteoarthritic cartilage. Prrx1-Cre inducible H3.3K36M transgenic mice showed articular cartilage destruction and osteophyte formation. Conditional knockout Nsd1Prrx1-Cre mice, but not Nsd2Prrx1-Cre or Setd2Prrx1-Cre mice, replicated the phenotype of K36M/+; Prrx1-Cre mice. Immunostaining results showed decreased anabolic and increased catabolic activities in Nsd1Prrx1-Cre mice, along with decreased chondrogenic differentiation. Transcriptome and ChIP-seq data revealed that Osr2 was a key factor affected by Nsd1. Intra-articular delivery of Osr2 adenovirus effectively improved the homeostasis of articular cartilage in Nsd1Prrx1-Cre mice. In human osteoarthritic cartilages, both mRNA and protein levels of NSD1 and OSR2 were decreased. Our results indicate that NSD1-induced H3K36 methylations and OSR2 expression play important roles in articular cartilage homeostasis and OA. Targeting H3K36 methylation and OSR2 would be a novel strategy for OA treatment.
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Cartilagem Articular , Osteoartrite , Camundongos , Humanos , Animais , Condrócitos/metabolismo , Metiltransferases/metabolismo , Osteoartrite/patologia , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Camundongos Transgênicos , Homeostase , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismoRESUMO
The influence mechanism of biorelevant media on the dissolution of active pharmaceutical ingredients (APIs) is the key to their formulation design. The dissolution kinetics of naproxen (NAP) and indomethacin (IND) in biorelevant media was systematically investigated. The dissolution mechanism was analyzed by chemical potential gradient model to explore the influence of surfactant type, pH and ionic strength. Hexadecyl trimethyl ammonium bromide (CTAB) is superior to sodium dodecyl sulfate (SDS) in promoting the dissolution of NAP and IND by increasing the solubility and accelerating the surface reaction processes. The electrostatic repulsion between SDS and NAP and IND with the same negative charge facilitates the diffusion of API, while the mutual attraction between CTAB and NAP and IND is not conducive to diffusion. High pH was favorable for the dissolution of acidic NAP and IND, as the simultaneous increase in solubility, surface reaction constant, and diffusion constant. High ionic strength was beneficial for the surface reaction of NAP and IND, but hindered their diffusion. It was shown that the modeling results were in conformity with the in vitro experimental data. These results are expected to provide theoretical supports for the design of biorelevant media and pharmaceutical formulations in the pharmaceutical development.
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Tensoativos , Cetrimônio , Dodecilsulfato de Sódio , Cinética , Solubilidade , Preparações FarmacêuticasRESUMO
The major cause of treatment failure and mortality among medulloblastoma patients is metastasis intracranially or along the spinal cord. The molecular mechanisms driving tumor metastasis in Sonic hedgehog-driven medulloblastoma (SHH-MB) patients, however, remain largely unknown. In this study we define a tumor suppressive role of KMT2D (MLL2), a gene frequently mutated in the most metastatic ß-subtype. Strikingly, genetic mouse models of SHH-MB demonstrate that heterozygous loss of Kmt2d in conjunction with activation of the SHH pathway causes highly penetrant disease with decreased survival, increased hindbrain invasion and spinal cord metastasis. Loss of Kmt2d attenuates neural differentiation and shifts the transcriptional/chromatin landscape of primary and metastatic tumors toward a decrease in differentiation genes and tumor suppressors and an increase in genes/pathways implicated in advanced stage cancer and metastasis (TGFß, Notch, Atoh1, Sox2, and Myc). Thus, secondary heterozygous KMT2D mutations likely have prognostic value for identifying SHH-MB patients prone to develop metastasis.
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Soft nanoporous crystals with structural dynamics are among the most exciting recently discovered materials. However, designing or controlling a porous system with delicate softness that can recognize similar gas pairs, particularly for the promoted ability at increased temperature, remains a challenge. Here, we report a soft crystal (NTU-68) with a one-dimensional (1D) channel that expands and contracts delicately around 4 Å at elevated temperature. The completely different adsorption processes of propane (C3H8: kinetic dominance) and propylene (C3H6: thermodynamic preference) allow the crystal to show a sieving separation of this mixtures (9.9 min·g-1) at 273 K, and the performance increases more than 2-fold (20.4 min·g-1) at 298 K. This phenomenon is contrary to the general observation for adsorption separation: the higher the temperature, the lower the efficiency. Gas-loaded in situ powder X-ray analysis and modeling calculations reveal that slight pore expansion caused by the increased temperature provides plausible nanochannel for adsorption of the relatively smaller C3H6 while maintaining constriction on the larger C3H8. In addition, the separation process remains unaffected by the general impurities, demonstrating its true potential as an alternative sorbent for practical applications. Moving forward, the delicate crystal dynamics and promoted capability for molecular recognition provide a new route for the design of next-generation sieve materials.
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Zinc-air batteries (ZABs) have been considered as one of the most emerging systems for energy conversion and storage. However, the preparation of highly efficient oxygen reduction reaction (ORR) catalysts on an air cathode is still faced with significant challenges. Herein, we report a secondary nitrogen source strategy for fine-tuning the active center, which provides a carbon-based hierarchical porous catalyst (termed Co3O4@N/CNT-1000) for highly efficient ORR activity (E1/2 = 0.87 V, JL = 5.32 mA cm-2, and Eonset = 1.021 V) and excellent stability. Controlled experiments demonstrate that such high activity derives from the synergistic effect of cobalt tetroxide and bamboo-shaped carbon nanotubes doped with nitrogen, prepared by the pyrolysis of a two-dimensional metal-organic framework nanosheet (termed NTU-70) and melamine. Furthermore, the ZAB assembled with Co3O4@N/CNT-1000 displays high specific capacity (854 mA h g-1Zn) and power density (179 mW cm-2), excellent long-term cycling (330 h), and durable charging/discharging ability.
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An effective approach to synthesize polycrystalline Ni-Co-Mo sulfide (NiCoMoS) is developed through doping engineering coupled with chemical transformation. The polycrystalline NiCoMoS with enriched active edge sites is designed and fabricated on a Ni foam (NF) via a facile hydrothermal calcination and post-sulfidation approach, where the polycrystalline NiCoMoO4 precursor is elaborately prepared by doping Co ions into the NiMoO4 lattice and subsequently in-situ-converted into NiCoMoS with 3D architectures of ordered nanoneedle arrays. Benefiting from the unique 3D structure and synergistic effects of each component, the optimized needle-like NiCoMoS(2.0) arraying on a NF as a self-standing electrode exhibits superior electrochemical performances with a high specific charge (920.0 C g-1 at 1.0 A g-1), excellent rate capability, and good long-term stability. Furthermore, the assembled NiCoMoS//activated carbon hybrid device presents a satisfactory supercapacitor performance, affording an energy density of 35.2 W h kg-1 at a power density of 800.0 W kg-1 and competitive long-term stability (83.8% retention at 15 A g-1 after 10,000 cycles). Such a novel strategy may pave a new route for exploring other polymetallic sulfides with enriched, exposed active edge sites for energy-related applications.
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Highly efficient ethylene (C2H4) and acetylene (C2H2) separation is a great challenge and an important process in current industries. Herein, we finely tune a new family of 6-c metal-organic frameworks (MOFs) with crab-like carboxylic pincers for the recognition of a C2H2 tetramer and afford NTU-72 with high adsorption C2H2/C2H4 selectivity (56-441, 298 K) as well as unprecedented recovery of both highly pure C2H4 (99.95%) and C2H2 (99.36%). Furthermore, the effective binding of a C2H2 tetramer by NTU-72's carboxylic pincers has been revealed by gas-loaded crystallography and Raman spectral studies. Our work provides a novel approach for the selective binding of a small molecular cluster for designing high-performance MOFs.
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Although KMT2D, also known as MLL2, is known to play an essential role in development, differentiation, and tumor suppression, its role in pancreatic cancer development is not well understood. Here, we discovered a novel signaling axis mediated by KMT2D, which links TGF-ß to the activin A pathway. We found that TGF-ß upregulates a microRNA, miR-147b, which in turn leads to post-transcriptional silencing of KMT2D. Loss of KMT2D induces the expression and secretion of activin A, which activates a noncanonical p38 MAPK-mediated pathway to modulate cancer cell plasticity, promote a mesenchymal phenotype, and enhance tumor invasion and metastasis in mice. We observed a decreased KMT2D expression in human primary and metastatic pancreatic cancer. Furthermore, inhibition or knockdown of activin A reversed the protumoral role of KMT2D loss. These findings support a tumor-suppressive role of KMT2D in pancreatic cancer and identify miR-147b and activin A as novel therapeutic targets.