Methylation of a MITE insertion in the MdRFNR1-1 promoter is positively associated with its allelic expression in apple in response to drought stress.

Miniature inverted-repeat transposable elements (MITEs) are widely distributed in the plant genome and can be methylated. However, whether DNA methylation of MITEs is associated with induced allelic expression and drought tolerance is unclear. Here, we identified the drought-inducible MdRFNR1 (root-type ferredoxin-NADP+ oxidoreductase) gene in apple (Malus domestica). MdRFNR1 plays a positive role in drought tolerance by regulating the redox system, including increasing NADP+ accumulation and catalase and peroxidase activities and decreasing NADPH levels. Sequence analysis identified a MITE insertion (MITE-MdRF1) in the promoter of MdRFNR1-1 but not the MdRFNR1-2 allele. MdRFNR1-1 but not MdRFNR1-2 expression was significantly induced by drought stress, which was positively associated with the MITE-MdRF1 insertion and its DNA methylation. The methylated MITE-MdRF1 is recognized by the transcriptional anti-silencing factors MdSUVH1 and MdSUVH3, which recruit the DNAJ domain-containing proteins MdDNAJ1, MdDNAJ2, and MdDNAJ5, thereby activating MdRFNR1-1 expression under drought stress. Finally, we showed that MdSUVH1 and MdDNAJ1 are positive regulators of drought tolerance. These findings illustrate the molecular roles of methylated MITE-MdRF1 (which is recognized by the MdSUVH-MdDNAJ complex) in induced MdRFNR1-1 expression as well as the drought response of apple and shed light on the molecular mechanisms of natural variation in perennial trees.

An open-label, prospective trial to evaluate the efficacy and safety of ixazomib in combination with cyclophosphamide and dexamethasone in patients with newly diagnosed POEMS syndrome.

This open-label, prospective trial evaluated the combination of ixazomib, cyclophosphamide and dexamethasone (ICD) in 12 newly diagnosed POEMS syndrome patients. The study is registered with the Chinese Clinical Trials Registry (ChiCTR2000030072). The treatment protocol consisted of 12 cycles of the ICD regimen compromising ixazomib (4 mg on Days 1, 8 and 15), oral cyclophosphamide (300 mg on Days 1, 8 and 15) and dexamethasone (20 mg weekly). A total of 12 patients received a median of 10 (range: 3-23) cycles of the ICD regimen. The haematological response could be evaluated in 10 patients. The overall haematological response rate was 80% (8/10), with 30% (3/10) achieving complete haematological response, and the overall serum VEGF response rate and neurological response were 100% and 83.3% respectively. Two patients experienced grade 3/4 AEs, including diarrhoea (n = 1) and leukopenia (n = 1). The combination of ixazomib, cyclophosphamide and dexamethasone demonstrated both efficacy and safety in newly diagnosed POEMS syndrome, making it a viable treatment option.

The lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branch number by affecting brassinosteroid biosynthesis.

Branch number is one of the most important agronomic traits of fruit trees such as peach. Little is known about how LncRNA and/or miRNA modules regulate branching through transcription factors. Here, we used molecular and genetic tools to clarify the molecular mechanisms underlying brassinosteroid (BR) altering plant branching. We found that the number of sylleptic branch and BR content in pillar peach ('Zhaoshouhong') was lower than those of standard type ('Okubo'), and exogenous BR application could significantly promote branching. PpTCP4 expressed great differentially comparing 'Zhaoshouhong' with 'Okubo'. PpTCP4 could directly bind to DWARF2 (PpD2) and inhibited its expression. PpD2 was the only one differentially expressed key gene in the path of BR biosynthesis. At the same time, PpTCP4 was identified as a target of miR6288b-3p. LncRNA1 could act as the endogenous target mimic of miR6288b-3p and repress expression of miR6288b-3p. Three deletions and five SNP sites of lncRNA1 promoter were found in 'Zhaoshouhong', which was an important cause of different mRNA level of PpTCP4 and BR content. Moreover, overexpressed PpTCP4 significantly inhibited branching. A novel mechanism in which the lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branching number was proposed.

Global hypermethylation of the N6-methyladenosine RNA modification associated with apple heterografting.

Grafting can facilitate better scion performance and is widely used in plants. Numerous studies have studied the involvement of mRNAs, small RNAs, and epigenetic regulations in the grafting process. However, it remains unclear whether the mRNA N6-methyladenosine (m6A) modification participates in the apple (Malus x domestica Borkh.) grafting process. Here, we decoded the landscape of m6A modification profiles in 'Golden delicious' (a cultivar, Gd) and Malus prunifolia 'Fupingqiuzi' (a unique rootstock with resistance to environmental stresses, Mp), as well as their heterografted and self-grafted plants. Interestingly, global hypermethylation of m6A occurred in both heterografted scion and rootstock compared with their self-grafting controls. Gene Ontology (GO) term enrichment analysis showed that grafting-induced differentially m6A-modified genes were mainly involved in RNA processing, epigenetic regulation, stress response, and development. Differentially m6A-modified genes harboring expression alterations were mainly involved in various stress responses and fatty acid metabolism. Furthermore, grafting-induced mobile mRNAs with m6A and gene expression alterations mainly participated in ABA synthesis and transport (e.g. carotenoid cleavage dioxygenase 1 [CCD1] and ATP-binding cassette G22 [ABCG22]) and abiotic and biotic stress responses, which might contribute to the better performance of heterografted plants. Additionally, the DNA methylome analysis also demonstrated the DNA methylation alterations during grafting. Downregulated expression of m6A methyltransferase gene MdMTA (ortholog of METTL3) in apples induced the global m6A hypomethylation and distinctly activated the expression level of DNA demethylase gene MdROS1 (REPRESSOR OF SILENCING 1) showing the possible association between m6A and 5mC methylation in apples. Our results reveal the m6A modification profiles in the apple grafting process and enhance our understanding of the m6A regulatory mechanism in plant biological processes.

Understanding the Interface Enhancement Mechanisms of CFRP with the Polydopamine-Polyetheramine Interphase at the Molecular Level.

In this work, polydopamine (PDA) and polyetheramine D230 were selected to construct the PDA-D230 interphase between the carbon fiber (CF) and epoxy matrix. Density functional theory (DFT) and molecular dynamics (MD) simulations were performed to explore the interface enhancement mechanisms of a carbon fiber reinforced polymer (CFRP) with the PDA-D230 interphase from the molecular level. The adsorption characteristics of a PDA molecule on the CF surface were investigated using the DFT method. The results show that stronger π-π stacking interactions are formed due to the structure and orientation preference of the PDA molecule. The interfacial structures and properties of CFRP with the PDA-D230 interphase are derived from MD simulations. The PDA-D230 interphase on the CF surface induces stronger interfacial interaction energy, leading to the better load transfer between the CF and epoxy matrix. The existence of the PDA-D230 interphase on the CF surface can decrease the mean-square displacement (MSD) value and the free volume fraction of CFRP, which restricts the movement of epoxy atoms and inhibits the translational and rotational motion of epoxy chains. Compared with the epoxy using pristine CFs as reinforcement, the interfacial shear stress (ISS) of CFRP with the PDA-D230 interphase is improved by 13.1%. Our results provide valuable insights into the interface characteristics of CFRP with the PDA-D230 interphase, which are of great significance for exploring the strengthening mechanisms for CFRPs with the PDA-D230 interphase.

MdGH3.6 is targeted by MdMYB94 and plays a negative role in apple water-deficit stress tolerance.

Drought significantly limits apple fruit production and quality. Decoding the key genes involved in drought stress tolerance is important for breeding varieties with improved drought resistance. Here, we identified GRETCHEN HAGEN3.6 (GH3.6), an indole-3-acetic acid (IAA) conjugating enzyme, to be a negative regulator of water-deficit stress tolerance in apple. Overexpressing MdGH3.6 reduced IAA content, adventitious root number, root length and water-deficit stress tolerance, whereas knocking down MdGH3.6 and its close paralogs increased IAA content, adventitious root number, root length and water-deficit stress tolerance. Moreover, MdGH3.6 negatively regulated the expression of wax biosynthetic genes under water-deficit stress and thus negatively regulated cuticular wax content. Additionally, MdGH3.6 negatively regulated reactive oxygen species scavengers, including antioxidant enzymes and metabolites involved in the phenylpropanoid and flavonoid pathway in response to water-deficit stress. Further study revealed that the homolog of transcription factor AtMYB94, rather than AtMYB96, could bind to the MdGH3.6 promoter and negatively regulated its expression under water-deficit stress conditions in apple. Overall, our results identify a candidate gene for the improvement of drought resistance in fruit trees.

The positive feedback regulatory loop of miR160-Auxin Response Factor 17-HYPONASTIC LEAVES 1 mediates drought tolerance in apple trees.

Drought stress tolerance is a complex trait regulated by multiple factors. Here, we demonstrate that the miRNA160-Auxin Response Factor 17 (ARF17)-HYPONASTIC LEAVES 1 module is crucial for apple (Malus domestica) drought tolerance. Using stable transgenic plants, we found that drought tolerance was improved by higher levels of Mdm-miR160 or MdHYL1 and by decreased levels of MdARF17, whereas reductions in MdHYL1 or increases in MdARF17 led to greater drought sensitivity. Further study revealed that modulation of drought tolerance was achieved through regulation of drought-responsive miRNA levels by MdARF17 and MdHYL1; MdARF17 interacted with MdHYL1 and bound to the promoter of MdHYL1. Genetic analysis further suggested that MdHYL1 is a direct downstream target of MdARF17. Importantly, MdARF17 and MdHYL1 regulated the abundance of Mdm-miR160. In addition, the Mdm-miR160-MdARF17-MdHYL1 module regulated adventitious root development. We also found that Mdm-miR160 can move from the scion to the rootstock in apple and tomato (Solanum lycopersicum), thereby improving root development and drought tolerance of the rootstock. Our study revealed the mechanisms by which the positive feedback loop of Mdm-miR160-MdARF17-MdHYL1 influences apple drought tolerance.

Decellularized tympanic membrane scaffold with bone marrow mesenchymal stem cells for repairing tympanic membrane perforation.

BACKGROUND: Tympanic membrane perforation (TMP) is a common disease in otology, and few acellular techniques have been reported for repairing this condition. Decellularized extracellular matrix (ECM) scaffolds have been used in organ reconstruction. OBJECTIVE: This study on tissue engineering aimed to develop a tympanic membrane (TM) scaffold prepared using detergent immersion and bone marrow mesenchymal stem cells (BMSCs) as repair materials to reconstruct the TM. RESULTS: General structure was observed that the decellularized TM scaffold with BMSCs retained the original intact anatomical ECM structure, with no cell residue, as observed using scanning electron microscopy (SEM), and exhibited low immunogenicity. Therefore, we seeded the decellularized TM scaffold with BMSCs for recellularization. Histology and eosin staining, SEM and immunofluorescence in vivo showed that the recellularized TM patch had a natural ultrastructure and was suitable for the migration and proliferation of BMSCs. The auditory brainstem response (ABR) evaluated after recellularized TM patch repair was slightly higher than that of the normal TM, but the difference was not significant. CONCLUSION: The synthetic ECM scaffold provides temporary physical support for the three-dimensional growth of cells during the tissue developmental stage. The scaffold stimulates cells to secrete their own ECM required for tissue regeneration. The recellularized TM patch shows potential as a natural, ultrastructure biological material for TM reconstruction.

Long Non-Coding RNA Malat1 Increases the Rescuing Effect of Quercetin on TNFα-Impaired Bone Marrow Stem Cell Osteogenesis and Ovariectomy-Induced Osteoporosis.

Osteoporosis, a common systematic bone homeostasis disorder related disease, still urgently needs innovative treatment methods. Several natural small molecules were found to be effective therapeutics in osteoporosis. In the present study, quercetin was screened out from a library of natural small molecular compounds by a dual luciferase reporter system. Quercetin was found to upregulate Wnt/ß-catenin while inhibiting NF-κB signaling activities, and thereby rescuing osteoporosis-induced tumor necrosis factor alpha (TNFα) impaired BMSCs osteogenesis. Furthermore, a putative functional lncRNA, Malat1, was shown to be a key mediator in quercetin regulated signaling activities and TNFα-impaired BMSCs osteogenesis, as mentioned above. In an ovariectomy (OVX)-induced osteoporosis mouse model, quercetin administration could significantly rescue OVX-induced bone loss and structure deterioration. Serum levels of Malat1 were also obviously rescued in the OVX model after quercetin treatment. In conclusion, our study demonstrated that quercetin could rescue TNFα-impaired BMSCs osteogenesis in vitro and osteoporosis-induced bone loss in vivo, in a Malat1-dependent manner, suggesting that quercetin may serve as a therapeutic candidate for osteoporosis treatment.

Novel Hepatic Schistosomula Antigens as Promising Targets for Immunodiagnosis and Immunoprotection of Schistosomiasis japonica.

BACKGROUND: Antigens of migrating schistosomula are promising candidates as schistosomiasis vaccine targets, since immune attack on hepatic schistosomula would interrupt the parasites life cycle and reduce egg burden on the host. METHODS: In this study, we report a collection of Schistosoma japonicum schistosomula proteins (SjScPs) that are highly expressed in hepatic schistosomula. The expression characteristics, antigenicity and immune protection of these proteins were studied by western blot, ELISA, immunofluorescence and challenge assays. RESULTS: We found that several of these SjScPs were highly antigenic and could effectively stimulate humoral immune responses in both human and other mammalian hosts. In particular, SjScP25, SjScP37, SjScP41, SjScP80, and SjScP88 showed high potential as biomarkers for schistosomiasis immunodiagnosis. Furthermore, we demonstrated that immunization with several of the recombinant SjScPs were able to protect mice from S japonicum challenge infection, with SjScP25 generating the most protective results. CONCLUSIONS: Our work represents a group of novel schistosome immunogens, which may be promising schistosomiasis japonica diagnosis and vaccine candidates.