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Visualization of multiple targets in living cells is important for understanding complex biological processes, but it still faces difficulties, such as complex operation, difficulty in multiplexing, and expensive equipment. Here, we developed a nanoplatform integrating a nucleic acid aptamer and DNA nanotechnology for living cell imaging. Aptamer-based recognition probes (RPs) were synthesized through rolling circle amplification, which were further self-assembled into DNA nanoflowers encapsulated by an aptamer loop. The signal probes (SPs) were obtained by conjugation of multicolor emission carbon quantum dots with oligonucleotides complementary to RPs. Through base pairing, RPs and SPs were hybridized to generate aptamer sgc8-, AS1411-, and Apt-based imaging systems. They were used for individual/simultaneous imaging of cellular membrane protein PTK7, nucleolin, and adenosine triphosphate (ATP) molecules. Fluorescence imaging and intensity analysis showed that the living cell imaging system can not only specifically recognize and efficiently bind their respective targets but also provide a 5-10-fold signal amplification. Cell-cycle-dependent distribution of nucleolin and concentration-dependent fluorescence intensity of ATP demonstrated the utility of the system for tracking changes in cellular status. Overall, this system shows the potential to be a simple, low-cost, highly selective, and sensitive living cell imaging platform.

Main Conclusion: A mutation was first found to cause the great generation of glutelin precursors (proglutelins) in rice (Oryza sativa L.) endosperm, and thus referred to as GPGG1. The GPGG1 was involved in synthesis and compartmentation of storage proteins. The PPR-like gene in GPGG1-mapped region was determined as its candidate gene. In the wild type rice, glutelins and prolamins are synthesized on respective subdomains of rough endoplasmic reticulum (ER) and intracellularly compartmentalized into different storage protein bodies. In this study, a storage protein mutant was obtained and characterized by the great generation of proglutelins combining with the lacking of 13 kD prolamins. A dominant genic-mutation, referred to as GPGG1, was clarified to result in the proteinous alteration. Novel saccular composite-ER was shown to act in the synthesis of proglutelins and 14 kD prolamins in the mutant. Additionally, a series of organelles including newly occurring several compartments were shown to function in the transfer, trans-plasmalemmal transport, delivery, deposition and degradation of storage proteins in the mutant. The GPGG1 gene was mapped to a 67.256 kb region of chromosome 12, the pentatricopeptide repeat (PPR)-like gene in this region was detected to contain mutational sites., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Keloids are benign skin tumors resulting from the excessive proliferation of connective tissue in wound skin. Precise prediction of keloid risk in trauma patients and timely early diagnosis are of paramount importance for in-depth keloid management and control of its progression. This study analyzed four keloid datasets in the high-throughput gene expression omnibus (GEO) database, identified diagnostic markers for keloids, and established a nomogram prediction model. Initially, 37 core protein-encoding genes were selected through weighted gene co-expression network analysis (WGCNA), differential expression analysis, and the centrality algorithm of the protein-protein interaction network. Subsequently, two machine learning algorithms including the least absolute shrinkage and selection operator (LASSO) and the support vector machine-recursive feature elimination (SVM-RFE) were used to further screen out four diagnostic markers with the highest predictive power for keloids, which included hepatocyte growth factor (HGF), syndecan-4 (SDC4), ectonucleotide pyrophosphatase/phosphodiesterase 2 (ENPP2), and Rho family guanosine triphophatase 3 (RND3). Potential biological pathways involved were explored through gene set enrichment analysis (GSEA) of single-gene. Finally, univariate and multivariate logistic regression analyses of diagnostic markers were performed, and a nomogram prediction model was constructed. Internal and external validations revealed that the calibration curve of this model closely approximates the ideal curve, the decision curve is superior to other strategies, and the area under the receiver operating characteristic curve is higher than the control model (with optimal cutoff value of 0.588). This indicates that the model possesses high calibration, clinical benefit rate, and predictive power, and is promising to provide effective early means for clinical diagnosis.

Pydiflumetofen is a novel and efficient broad-spectrum chiral fungicide consisting of a pair of enantiomers. A simple and sensitive chiral analytical method was established to determine the enantiomers of this chiral fungicide in food and environmental samples by ultra-high-performance liquid chromatography tandem triple quadrupole mass spectrometry (UHPLC-MS/MS) using QuEChERS method coupled with octadecylsilane-dispersive solid-phase extraction (C 18 -dSPE) as extraction procedure. The specific optical rotation and the absolute configuration of the enantiomers were identified by polarimetry and electronic circular dichroism (ECD). The elution order of the pydiflumetofen enantiomers on Lux Cellulose-2 was S-(-)-pydiflumetofen and R-(+)-pydiflumetofen. The average recoveries of eleven matrices ranged from 71.3% to 107.4%. The intraday relative standard deviations (RSDs) were less than 11.8%, and the interday RSDs were less than 12.6% for the two enantiomers. Stereoselective dissipation in pakchoi and soil were observed: S-(-)-pydiflumetofen was degraded faster than R-(+)-pydiflumetofen in pakchoi, causing the enantiomer fraction (EF) of the enantiomers to change from 0.50 to 0.42 in 7 days. However, R-(+)-pydiflumetofen was degraded faster than S-(-)-pydiflumetofen in soil, causing the EF of the enantiomers to change from 0.49 to 0.52 in 21 days. This study provides a method for monitoring pydiflumetofen enantiomer residues, which is crucial for improving risk assessments and the development of chiral pesticides., (Copyright © 2020 Elsevier Inc. All rights reserved.)

High hardness and corrosion resistance of SiC (silicon carbide) bulk materials have always been a difficult problem in the processing of an all-SiC piezoresistive pressure sensor. In this work, we demonstrated a SiC sealing cavity structure utilizing SiC shallow plasma-etched process (≤20 μm) and SiC-SiC room temperature bonding technology. The SiC bonding interface was closely connected, and its average tensile strength could reach 6.71 MPa. In addition, through a rapid thermal annealing (RTA) experiment of 1 min and 10 mins in N 2 atmosphere of 1000 °C, it was found that Si, C and O elements at the bonding interface were diffused, while the width of the intermediate interface layer was narrowed, and the tensile strength could remain stable. This SiC sealing cavity structure has important application value in the realization of an all-SiC piezoresistive pressure sensor.

Silver nanoparticle (Ag NP)-coated carbon quantum dot (CQD) core-shell-structured nanocomposites (CQD@Ag NCs) were developed for fluorescent imaging of intracellular superoxide anion (O 2 •- ). The morphology of CQD@Ag NCs was investigated by transmission electron microscopy, and the composition was characterized by X-ray diffraction and X-ray photoelectron spectroscopy. CQDs display blue fluorescence with excitation/emission maxima at 360/440 nm, and the fluorescence was quenched by Ag NPs in CQD@Ag NCs. In the presence of O 2 •- , Ag NPs were oxide-etched and the fluorescence of CQDs was recovered. A linearity between the relative fluorescence intensity and O 2 •- solution concentration within the range 0.6 to 1.6 μM was found, with a detection limit of 0.3 μM. Due to their high sensitivity, selectivity, and low cytotoxicity, the as-synthesized CQD@Ag NCs have been successfully applied for imaging of O 2 •- in MCF-7 cells during the whole process of autophagy induced by serum starvation. In our perception, the developed method provides a cost-effective, sensitive, and selective tool in bioimaging and monitoring of intracellular O 2 •- changes, and is promising for potential biological applications. Graphical abstract Illustration of the synthesis of carbon quantum Dot@Silver nanocomposites (CQD@Ag NCs), and CQD@Ag NCs as a "turn-on" nanoprobe for fluorescent imaging of intracellular superoxide anion.

Cysteine is the first organic molecule generated during the assimilation of sulfate. As such, cysteine and its derivatives are always essential signal molecules and thus have important roles in the regulation of many plant processes. O-acetylserine (thiol) lyase (OASTL) catalyzes the last step of the biosynthesis of cysteine. At present, detailed and comprehensive work about these enzymes has only been reported from the plant Arabidopsis thaliana, though sporadic studies on OASTL have been conducted on other dicots, such as spinach and soybean. However, few reports on the functions of OASTLs in monocots have been found in the literature. Here in this study, we obtained four SiOASTL genes (SiOASTL7, SiOASTL8, SiOASTL9 and SiOASTL10) from foxtail millet and analyzed their potential functions. Phylogenetically, the four SiOASTL genes did not belong to any published subfamily of the OASTL genes; instead they constituted a new subfamily specific to the OASTL genes from monocots. In sequencing, we found that with the exception of the pseudogene SiOASTL8, proteins encoded by the other three genes exhibited high similarity with OASTL proteins from Arabidopsis, though the critical PLP-binding sites of both SiOASTL7 and SiOASTL10 were missing. The enzymatic activity assays demonstrated that SiOASTL9 has the ability to catalyze the biosynthesis of both cysteine and S-sulfocysteine, while SiOASTL7 and SiOASTL10 did not possess any previously reported catalyzing abilities. In addition, the gene expression pattern analysis showed that all four genes were widely expressed in various tissues of foxtail millet, and all had a preference in the leaves. Under abiotic stresses, the expression of these genes could be induced by salt and drought stress. Our finding that cadmium could only up-regulate the transcription of SlOASTL8 and SlOASTL9, further indicates the diversified responses of SiOASTLs to abiotic stresses., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

This paper presents a novel manipulation method for micro-objects using acoustically oscillating bubbles with a controllable position based on the gas permeability of polydimethylsiloxane. The oscillating bubble trapped within the side channel attracts the neighboring micro-objects, and the position of the air-liquid interface is controlled by generating temporary pressure difference between the side channel and the air channel. To demonstrate the feasibility of the method in technological applications, polystyrene microparticles of 10  μ m in diameter were successfully captured, transported, and released. The influence of pressure difference on the movement speed of the air-liquid interface was demonstrated in our experiments, and the manipulation performance was also characterized by varying the frequency of the acoustic excitation and the pressure difference. Since the bubble generation and the air-liquid interface movement in our manipulation method do not need any electrochemical reaction and any high temperature, this on-chip manipulation method provides a controllable, efficient, and noninvasive tool for handling micro-objects such as particles, cells, and other entities. The whole manipulation process, including capturing, transporting, and releasing of particles, spent less than 1 min. It can be used to select the cells and particles in the microfluidic device or change the cell culture medium.

Methyl jasmonate (MeJA), a vital cellular regulator, mediates diverse developmental processes and defense responses against environmental stresse. Recently, a novel gasotransmitter, hydrogen sulfide (H2S), was found to have similar functions, but the interactions between H2S and MeJA in the acquisition of cadmium (Cd) tolerance have not been reported. Treating foxtail millet with 1 microM MeJA not only enhanced Cd tolerance and alleviated growth inhibitions but also decreased the contents of hydrogen peroxide, malondialdehyde and Cd in seedlings under 200 microM of Cd stress. Exogenous application of MeJA inhibited the transcript levels of the Natural Resistance-Associated Macrophage Protein (NRAMP1 and NRAMP6) and intensified Cd-induced expression of the homeostasis-related genes (MTP1, MTP12, CAX2 and ZIP4, besides HMA3). In addition, treatment with MeJA induced the production of endogenous H2S. Fumigation with sodium hydrosulfide (H2S donor) significantly enhanced MeJA-induced Cd tolerance, but this ability was weakened when H2S biosynthesis was inhibited with hydroxylamine. These results suggest that pretreatment with MeJA alleviated Cd stress and that this improvement was mediated by H2S in foxtail millet.

Hydrogen sulfide (H 2 S) and some functional amino acids in crops have been involved in the defense system against heavy-metal pollution. Here we report the relationships and functions of H 2 S and proline to cadmium (Cd) stress. Sodium hydrosulfide (NaHS) pretreatment decreased the electrolytic leakage and the malondialdehyde and hydrogen peroxide contents while enhancing photosynthesis in Cd-treated seedlings. Furthermore, pretreatment with NaHS markedly exacerbated Cd-induced alterations in proline content, the activities of proline-5-carboxylate reductase (P5CR) and proline dehydrogenase (PDH), and the transcript levels of P5CR and PDH. When endogenous H 2 S was scavenged or inhibited by various H 2 S modulators, the Cd-induced increase in endogenous proline was weakened. Combined pretreatment with H 2 S and proline was moderately higher in the Cd-stressed growth status, stomata movements and oxidative damage of seedlings compared to a single treatment with H 2 S or proline. These results suggest that H 2 S and proline cooperate to alleviate Cd-damage in foxtail millet., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

The d2003 is a natural dwarf mutant from maize inbred line K36 and has less than one-third of K36 plant height with severely shortened internodes. In this study, we reported the cloning of d2003 gene using positional cloning. The results showed that there was a single-base insertion in the coding region of Viviparous8 (VP8) in d2003 mutant, which resulted in a premature stop codon. Further genetic allelism tests confirmed that d2003 mutation is a novel allele of VP8. VP8 is mainly expressed in the stem apex, young leaves, and developing vascular tissues, and its expression levels in nodes are significantly higher than that in internodes at 12-leaf stage. Subcellular localization demonstrated that the VP8 protein is localized to the endoplasmic reticulum and the N-terminal 26 amino acids (aa) of VP8 protein are essential to its localization in ER. Further transgenic experiments showed that lack of the 26 aa leads to loss of VP8 function in Arabidopsis amp1 phenotype rescue. These results strongly suggested that the N-terminal 26 aa is critical for VP8 protein localization, and the correct protein localization of VP8 in ER is necessary for its function.

Hydrogen sulfide (H(2)S) plays a crucial role in the regulation of stomatal closure in plant response to drought stress, and l-cysteine desulfhydrase (LCD) has been identified as being mainly responsible for the degradation of cysteine to generate H(2)S. In view of the similar roles to abscisic acid (ABA), in this study, the lcd, aba3 and abi1 mutants were studied to investigate the close inter-relationship between H(2)S and ABA. The lcd mutant showed enlarged stomatal aperture and more sensitivity to drought stress than wild-type plants. Expression of Ca(2+) channel and outward-rectifying K(+) channel coding genes decreased in the lcd mutant, and conversely, expression of inward-rectifying K(+) increased. The stomatal aperture of aba3 and abi1 mutants decreased after treatment with NaHS (a H(2)S donor), but stomatal closure in responses to ABA was impaired in the lcd mutant. The expression of LCD and H(2)S production rate decreased in both the aba3 and abi1 mutants. Transcriptional expression of ABA receptor candidates was upregulated in the lcd mutant and decreased with NaHS treatment. The above results suggested that H(2)S may be an important link in stomatal regulation by ABA via ion channels; H(2)S affected the expression of ABA receptor candidates; and ABA also influenced H(2)S production. Thus, H(2)S interacted with ABA in the stomatal regulation responsible for drought stress in Arabidopsis., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Deep-seeding tolerant seeds can emerge from deep soil where the moisture is suitable for seed germination. Breeding deep-seeding tolerant cultivars is becoming increasingly important in arid and semi-arid regions. To dissect the quantitative trait loci (QTL) controlling deep-seeding tolerance traits, we selected a tolerant maize inbred line 3681-4 and crossed it with the elite inbred line-X178 to generate an F(2) population and the derivative F(2:3) families. A molecular linkage map composed of 179 molecular markers was constructed, and 25 QTL were detected including 10 QTL for sowing at 10 cm depth and 15 QTL for sowing at 20 cm depth. The QTL analysis results confirmed that deep-seeding tolerance was mainly caused by mesocotyl elongation and also revealed considerable overlap among QTL for different traits. To confirm a major QTL on chromosome 10 for mesocotyl length measured at 20 cm depth, we selected and self-pollinated a BC(3)F(2) plant that was heterozygous at the markers around the target QTL and homozygous at other QTL to generate a BC(3)F(3) population. We found that this QTL explained more phenotypic variance in the BC(3)F(3) population than that in the F(2) population, which laid the foundation for fine mapping and NIL (near-isogenic line) construction.