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Bone tissue engineering provides a promising strategy for the treatment of bone defects. Nonetheless, the clinical utilization of biomaterial-based scaffolds is constrained by their inadequate mechanical strength and absence of osteo-inductive properties. Here, we proposed to endow nano-scaffold (NS) constructed by coaxial electrospinning technique with enhanced osteogenic bioactivities and mechanical properties by incorporating biocompatible magnetic iron oxide nanoparticles (IONPs) and icaritin (ICA). Four types of nano-scaffolds (NS, ICA@NS, NS-IONPs and ICA@NS-IONPs) were prepared. The incorporation of ICA and IONPs minimally impact their surface morphological and chemical properties. IONPs enhanced the mechanical properties of NS scaffolds, including hardness, tensile strength, and elastic modulus. In vitro assessments demonstrated that ICA@NS-IONPs exhibited enhanced osteogenic bioactivities towards mouse calvarial pre-osteoblast cell line MC3T3-E1 as evidenced by detecting the alkaline phosphatase (ALP) activity level, expressions of osteogenesis-related genes and proteins as well as mineralized nodule formation. Mechanistic investigations revealed that MEK/ERK (MAP kinase-ERK kinase (MEK)/extracellular-signal-regulated kinase (ERK)) signaling pathway could offer a plausible explanation for the osteogenic differentiation of MC3T3-E1 cells induced by ICA@NS-IONPs. Furthermore, the implantation of nano-scaffolds in rat skull defects exhibited a substantial improvement in in vivo bone regeneration. Therefore, IONPs and ICA incorporated coaxial electrospinning nano-scaffolds present a novel strategy for the optimization of scaffolds for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Tiller number greatly contributes to grain yield in wheat. Using ethylmethanesulfonate mutagenesis, we previously discovered the oligo-tillering mutant ot1. The tiller number was significantly lower in ot1 than in the corresponding wild type from the early tillering stage until the heading stage. Compared to the wild type, the thousand-grain weight and grain length were increased by 15.41% and 31.44%, respectively, whereas the plant height and spike length were decreased by 26.13% and 37.25%, respectively. Transcriptomic analysis was conducted at the regreening and jointing stages to identify differential expressed genes (DEGs). Functional enrichment analysis with the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) databases showed differential expression of genes associated with ADP binding, transmembrane transport, and transcriptional regulation during tiller development. Differences in tiller number in ot1 led to the upregulation of genes in the strigolactone (SL) and abscisic acid (ABA) pathways. Specifically, the SL biosynthesis genes DWARF (D27), D17, D10, and MORE AXILLARY GROWTH 1 (MAX1) were upregulated by 3.37- to 8.23-fold; the SL signal transduction genes D14 and D53 were upregulated by 1.81- and 1.32-fold, respectively; the ABA biosynthesis genes 9-CIS-EPOXICAROTENOID DIOXIGENASE 3 (NCED3) and NCED5 were upregulated by 1.66- and 3.4-fold, respectively; and SNF1-REGULATED PROTEIN KINASE2 (SnRK2) and PROTEIN PHOSPHATASE 2C (PP2C) genes were upregulated by 1.30- to 4.79-fold. This suggested that the tiller number reduction in ot1 was due to alterations in plant hormone pathways. Genes known to promote tillering growth were upregulated, whereas those known to inhibit tillering growth were downregulated. For example, PIN-FORMED 9 (PIN9), which promotes tiller development, was upregulated by 8.23-fold in ot1; Ideal Plant Architecture 1 (IPA1), which inhibits tiller development, was downregulated by 1.74-fold. There were no significant differences in the expression levels of TILLER NUMBER 1 (TN1) or TEOSINTE BRANCHED 1 (TB1), indicating that the tiller reduction in ot1 was not controlled by known genes. Our findings provide valuable data for subsequent research into the genetic bases and regulatory mechanisms of wheat tillering. [ABSTRACT FROM AUTHOR]

In this study, an efficient visible light responsive MIL-125(Ti)/ZnIn2S4 hybrid structure (MIL-1.2/ZIS) was synthesized through two-step method with improved photocatalytic H2-evolution performance. The MIL-1.2/ZIS nanocomposites could retained the characteristic features including the highly surface area of metal organic frameworks and the hierarchical sheet-like structure of ZnIn2S4. The optimal sample could exhibit the H2 generation rate of 873.4 μmol g−1·h−1, and the improved photocatalytic activity could be ascribed to the well-matched band structure and the formation of hybrid interfaces, which could lead to the effective charge transfer and separation of photo-excited electron–hole pairs. We hope this paper could broad the potential utilization of MOF-based nanocomposites in photocatalytic energy conversion fields. [ABSTRACT FROM AUTHOR]

Key message: A minor-effect QTL, Qhd.2AS, that affects heading date in wheat was mapped to a genomic interval of 1.70-Mb on 2AS, and gene analysis indicated thatthe C2H2-type zinc finger proteingene TraesCS2A02G181200is the best candidate for Qhd.2AS. Heading date (HD) is a complex quantitative trait that determines the regional adaptability of cereal crops, and identifying the underlying genetic elements with minor effects on HD is important for improving wheat production in diverse environments. In this study, a minor QTL for HD that we named Qhd.2AS was detected on the short arm of chromosome 2A by Bulked Segregant Analysis and validated in a recombinant inbred population. Using a segregating population of 4894 individuals, Qhd.2AS was further delimited to an interval of 0.41 cM, corresponding to a genomic region spanning 1.70 Mb (from 138.87 to 140.57 Mb) that contains 16 high-confidence genes based on IWGSC RefSeq v1.0. Analyses of sequence variations and gene transcription indicated that TraesCS2A02G181200, which encodes a C2H2-type zinc finger protein, is the best candidate gene for Qhd.2AS that influences HD. Screening a TILLING mutant library identified two mutants with premature stop codons in TraesCS2A02G181200, both of which exhibited a delay in HD of 2–4 days. Additionally, variations in its putative regulatory sites were widely present in natural accession, and we also identified the allele which was positively selected during wheat breeding. Epistatic analyses indicated that Qhd.2AS-mediated HD variation is independent of VRN-B1 and environmental factors. Phenotypic investigation of homozygous recombinant inbred lines (RILs) and F2:3 families showed that Qhd.2AS has no negative effect on yield-related traits. These results provide important cues for refining HD and therefore improving yield in wheat breeding programs and will deepen our understanding of the genetic regulation of HD in cereal plants. [ABSTRACT FROM AUTHOR]

Particle surface morphology is an important factor influencing sand structure and mechanical properties. In this study, the effect of sand particle sphericity on sand direct shear performance is investigated by using the discrete element method (DEM). Two ways are adapted to simulate different approaching methods from round particles to irregular sand. The macroresponse shows that irregular sand has a higher shear strength at lower normal stress than round particles. The shape of the particle has less influence on shear strength at higher normal stress. The irregular shape of sand leads to an increase in the shear band proportion. However, the shear band proportion is not related to the sphericity. Under all conditions, particles within the shear band have a larger average rotation angle than those outside the shear band. When the particle shape approaches round (regardless of the round particle proportion and particle shape), the average rotation angle of particles within and without shear bands increase, while the coordinate number and contact anisotropy decrease. [ABSTRACT FROM AUTHOR]

To identify novel allelic variations in key genes of wheat quality, the present study used the targeting induced local lesions in genomes platform to detect point mutations in target genes. The wheat variety Longfumai 17 was treated by the mutagen ethyl methanesulfonate to produce a bulk M generation, and the population included 1122 plants. A total length of 3906.80 kb nucleotides was analyzed, and the average mutation density was 1/244.17 kb. The identified mutations included G>A substitutions (43.75%), C>T substitutions (31.25%), A insertions (12.50%), T insertions (6.25%), and deletions (6.25%). These point mutations led to changes in amino acids and thus the encoded protein sequences, ultimately producing 18.75% of missense mutations, 12.50% of frame shift mutations, 6.25% of nonsense mutations, 25.00% of silent mutations and 37.50% of non-coding region mutations. In the kernel hardness gene Pinb and 3 starch synthesis genes waxy, Agp2 and SSIIa-A, we detected 16 different point mutations in 25 mutant lines. The Pinb gene harbored two missense mutations and a nonsense mutation; the C>T missense mutation resulted in a novel allele, this novel allele and the nonsense mutation alerted protein 3D structure; the waxy gene presented missense and frame shift mutations; the Agp2 gene carried a missense mutation; the SSIIa-A incurred a missense mutation and a frame shift mutation that resulted in premature protein termination. All the frame shift mutations, nonsense mutations and the Pinb novel allele resulted in allelic variation of their corresponding genes, which in turn affected their gene functions. The identified mutant lines can be used as intermediate materials in wheat quality improvement schemes. [ABSTRACT FROM AUTHOR]

The melastatin-like transient receptor potential 7 (TRPM7) has been implicated in proliferation or apoptosis of some cancers, indicating the potential of TRPM7 as an anti-anaplastic target. Here, we identified the characteristic TRPM7 channel currents in human malignant glioma MGR2 cells, which could be blocked by a pharmacologic inhibitor Gd. We mined the clinical sample data from Oncomine Database and found that human malignant glioma tissues expressed higher TRPM7 mRNA than normal brain ones. Importantly, we identified a widely used clinical anesthetic midazolam as a TRPM7 inhibitor. Midazolam treatment for seconds suppressed the TRPM7 currents and calcium influx, and treatment for 48 h inhibited the TRPM7 expression. The inhibitory effect on TRPM7 accounts for the proliferation loss and G/G phase cell cycle arrest induced by midazolam. Our data demonstrates that midazolam represses proliferation of human malignant glioma cells through inhibiting TRPM7 currents, which may be further potentiated by suppressing the expression of TRPM7. Our result indicates midazolam as a pharmacologic lead compound with brain-blood barrier permeability for targeting TRPM7 in the glioma. [ABSTRACT FROM AUTHOR]

Demonstrates that the rga5 is a functional gene encoding gibberellin 20-oxidase in rice. Increase in the endogenous GA[sub 1] level and plant height of rice by over-expressing rga5; Effect of overexpression and antisense-expression on the biological characters of rice.