Whole-genome sequencing of diverse wheat accessions uncovers genetic changes during modern breeding in China and the United States.

Breeding has dramatically changed the plant architecture of wheat (Triticum aestivum), resulting in the development of high-yielding varieties adapted to modern farming systems. However, how wheat breeding shaped the genomic architecture of this crop remains poorly understood. Here, we performed a comprehensive comparative analysis of a whole-genome resequencing panel of 355 common wheat accessions (representing diverse landraces and modern cultivars from China and the United States) at the phenotypic and genomic levels. The genetic diversity of modern wheat cultivars was clearly reduced compared to landraces. Consistent with these genetic changes, most phenotypes of cultivars from China and the United States were significantly altered. Of the 21 agronomic traits investigated, 8 showed convergent changes between the 2 countries. Moreover, of the 207 loci associated with these 21 traits, more than half overlapped with genomic regions that showed evidence of selection. The distribution of selected loci between the Chinese and American cultivars suggests that breeding for increased productivity in these 2 regions was accomplished by pyramiding both shared and region-specific variants. This work provides a framework to understand the genetic architecture of the adaptation of wheat to diverse agricultural production environments, as well as guidelines for optimizing breeding strategies to design better wheat varieties.

Deciphering the Genetic Basis of Silkworm Cocoon Colors Provides New Insights into Biological Coloration and Phenotypic Diversification.

The genetic basis of phenotypic variation is a long-standing concern of evolutionary biology. Coloration has proven to be a visual, easily quantifiable, and highly tractable system for genetic analysis and is an ever-evolving focus of biological research. Compared with the homogenized brown-yellow cocoons of wild silkworms, the cocoons of domestic silkworms are spectacularly diverse in color, such as white, green, and yellow-red; this provides an outstanding model for exploring the phenotypic diversification and biological coloration. Herein, the molecular mechanism underlying silkworm green cocoon formation was investigated, which was not fully understood. We demonstrated that five of the seven members of a sugar transporter gene cluster were specifically duplicated in the Bombycidae and evolved new spatial expression patterns predominantly expressed in silk glands, accompanying complementary temporal expression; they synergistically facilitate the uptake of flavonoids, thus determining the green cocoon. Subsequently, polymorphic cocoon coloring landscape involving multiple loci and the evolution of cocoon color from wild to domestic silkworms were analyzed based on the pan-genome sequencing data. It was found that cocoon coloration involved epistatic interaction between loci; all the identified cocoon color-related loci existed in wild silkworms; the genetic segregation, recombination, and variation of these loci shaped the multicolored cocoons of domestic silkworms. This study revealed a new mechanism for flavonoids-based biological coloration that highlights the crucial role of gene duplication followed by functional diversification in acquiring new genetic functions; furthermore, the results in this work provide insight into phenotypic innovation during domestication.

Rapid molecular identification of Rana dybowskii by species-specific primers.

Oviductus Ranae is the dried oviduct from Rana dybowskii, a forest frog species with medicinal, tonic, and cosmetic properties. Due to the high price and resource shortage, counterfeit varieties of Oviductus Ranae often appear in the market. However, traditional identification methods cannot accurately differentiate between Oviductus Ranae and its adulterants. In this study, a rapid molecular identification method has been established. The method involves extracting genomic DNA in just 30 s using filter paper purification, species-specific rapid polymerase chain reaction (PCR) amplification, and finally, fluorescence detection of the products. It can accurately identify Oviductus Ranae and its three common adulterants in about 30 min, making the process simple, fast, and highly specific.

Visible-light promoted cascade cyanoalkylsulfonylation/ipso-cyclization of N-arylpropiolamides toward sulfonated spiro[4,5]trienones via SO2 insertion.

A novel visible-light induced sulfonylation/ipso-cyclization of N-arylpropiolamides with cyclobutanone oxime esters and Na2S2O5 was reported. This protocol proceeded via a radical process. The wide substrate scope, sustainable metal-free conditions and readily accessible reagents make this protocol an efficient and green strategy for the synthesis of cyanoalkyl sulfonated spiro[4,5]trienones.

Correlation between platelet-derived growth factor-B gene polymorphism and coronary heart disease.

OBJECT: The aim of the present work was to investigate the correlation of plasma platelet-derived growth factor (PDGF)-BB level and single nucleotide polymorphism (SNP, rs1800817 and rs2285094) of PDGF-B gene with the onset and stability condition of coronary heart disease (CHD). METHODS: Totally, 335 subjects were included in and divided into CHD (n = 247) and control group (n = 88) according to coronary angiography. Besides, the patients in the CHD group were divided into acute coronary syndrome (ACS) group (n = 165) and stable angina pectoria (SAP) group (n = 82), based on CHD stability condition. The plasma PDGF-BB level was measured by ELISA, and the genotype of PDGF-B was examined through qPCR assay. RESULTS: The PDGF-BB level was positively correlated with hsCRP level (r = 0.149, p < 0.05). The genotype frequencies of SNP rs1800817 and rs2285094 match Hardy-Weinberg equilibrium. There was weak linkage disequilibrium between SNP rs1800817 and rs2285094: D' = 0.419, r2  = 0.04, which has no correlation with CHD. There was no statistical difference in plasma PDGF-BB level among different genotypes in rs1800817 and rs2285094. There were no differences in the plasma PDGF-BB level among patients with any genotype of SNP rs1800817 and rs2285094, no matter how it was grouped. Logistic regression results indicated that the plasma PDGF-BB level was the independent risk factor of CHD onset (OR = 1.003, 95% CI 1.001-1.006, p = 0.014). CONCLUSIONS: High plasma PDGF-BB level is the risk factor of CHD and has correlation with instability of CHD. The plasma PDGF-BB level change may be related to inflammatory response. PDGF-B gene rs1800817 and rs2285094 polymorphisms are not correlated with CHD.

The Role of Chitooligosaccharidolytic ß-N-Acetylglucosamindase in the Molting and Wing Development of the Silkworm Bombyx mori.

The insect glycoside hydrolase family 20 ß-N-acetylhexosaminidases (HEXs) are key enzymes involved in chitin degradation. In this study, nine HEX genes in Bombyx mori were identified by genome-wide analysis. Bioinformatic analysis based on the transcriptome database indicated that each gene had a distinct expression pattern. qRT-PCR was performed to detect the expression pattern of the chitooligosaccharidolytic ß-N-acetylglucosaminidase (BmChiNAG). BmChiNAG was highly expressed in chitin-rich tissues, such as the epidermis. In the wing disc and epidermis, BmChiNAG has the highest expression level during the wandering stage. CRISPR/Cas9-mediated BmChiNAG deletion was used to study the function. In the BmChiNAG-knockout line, 39.2% of female heterozygotes had small and curly wings. The ultrastructure of a cross-section showed that the lack of BmChiNAG affected the stratification of the wing membrane and the formation of the correct wing vein structure. The molting process of the homozygotes was severely hindered during the larva to pupa transition. Epidermal sections showed that the endocuticle of the pupa was not degraded in the mutant. These results indicate that BmChiNAG is involved in chitin catabolism and plays an important role in the molting and wing development of the silkworm, which highlights the potential of BmChiNAG as a pest control target.

Quantitative features and clinical significance of two subpopulations of AChR-specific CD4+ T cells in patients with myasthenia gravis.

Acetylcholine receptor (AChR)-specific CD4+ T cells play a driving role in myasthenia gravis (MG) by regulating the production of autoantibodies. However, the quantitative features of AChR-specific T cells and their clinical significance in MG are unclear. In this study, we adopted standard and cultured enzyme-linked immunosorbent spot (ELISPOT) assays to quantify subpopulations of AChR-specific CD4+ T cells in MG patients, and evaluate their correlation with clinical characteristics. The results showed that Th1- and Th17-AChR-specific CD4+ T cells were detectable by standard and cultured ELISPOT assay respectively, with higher levels observed in MG patients comparing with healthy controls. The number of Th17-AChR-specific CD4+ T cells was positively correlated with anti-AChR antibody titer and quantitative MG score and may have latent capacity to reflect responses to immunosuppressants. These results highlight the differences in quantitative features of AChR-specific CD4+ T cells and imply Th17-AChR-specific CD4+ T cells can serve as a biomarker in MG.

Circulating Th1/17 cells serve as a biomarker of disease severity and a target for early intervention in AChR-MG patients.

Interleukin-17-expressing CD4+ T helper 17 (Th17) cells are considered to be critical regulators of thymic inflammation in AChR-MG patients. However, Th17 cells are functionally heterogeneous and circulating Th17 subsets are incompletely understood in AChR-MG patients. Here, we studied characteristics of Th17 subsets in peripheral blood from treatment-naïve AChR-MG patients, patients treated with immunosuppressants, as well as healthy controls. We found increased frequencies of circulating Th1-like Th17 (Th1/17) (IFN-γ + IL-17 + CD4 + CD3+) cells, which declined earlier than conventional Th17 (IFN-γ - IL-17 + CD4 + CD3+) cells in patients who respond well to immunosuppression treatment. Additionally, circulating Th1/17 cell frequencies were found to correlate positively with disease severity. Further, compared to conventional Th17 cells, Th1/17 cells showed an elevated expression of IFNG, TBX21, IL23R, CSF2, and a reduced expression of AHR and IL10. Taken together, our results suggest circulating Th1/17 cells may serve as a biomarker of disease severity and provide a strong rationale for early intervention in AChR-MG patients.

Glutamate synthase 1 is involved in iron-deficiency response and long-distance transportation in Arabidopsis.

Iron is an essential microelement for plant growth. After uptake from the soil, iron is chelated by ligands and translocated from roots to shoots for subsequent utilization. However, the number of ligands involved in iron chelation is unclear. In this study, we identified and demonstrated that GLU1, which encodes a ferredoxin-dependent glutamate synthase, was involved in iron homeostasis. First, the expression of GLU1 was strongly induced by iron deficiency condition. Second, lesion of GLU1 results in reduced transcription of many iron-deficiency-responsive genes in roots and shoots. The mutant plants revealed a decreased iron concentration in the shoots, and displayed severe leaf chlorosis under the condition of Fe limitation, compared to wild-type. Third, the product of GLU1, glutamate, could chelate iron in vivo and promote iron transportation. Last, we also found that supplementation of glutamate in the medium can alleviate cadmium toxicity in plants. Overall, our results provide evidence that GLU1 is involved in iron homeostasis through affecting glutamate synthesis under iron deficiency conditions in Arabidopsis.

Identification and Application of Epitopes in EtMIC1 of Eimeria tenella Recognized by the Monoclonal Antibodies 1-A1 and 1-H2.

Eimeria tenella microneme-1 protein (EtMIC1) has been proposed to be a transmembrane protein, but this characteristic has not yet been confirmed experimentally. Furthermore, despite EtMIC1 being an important candidate antigen, its key epitope has not been reported. Here, two linear B-cell epitopes of EtMIC1, 91LITFATRSK99 and 698ESLISAGE705, were identified by Western blotting using specific monoclonal antibodies (MAbs) and were named epitope I (located in the I-domain) and epitope CTR (located in the CTR domain), respectively. Sequence comparative analyses of these epitopes among Eimeria species that infect chickens showed that epitope I differs greatly across species, whereas epitope CTR is relatively conserved. Point mutation assay results indicate that all the amino acid residues of the epitopes recognized by MAb 1-A1 or 1-H2 are key amino acids involved in recognition. Comparative analyses of indirect immunofluorescence assay (IFA) results for MAbs 1-A1 and 1-H2 under both nonpermeabilization and permeabilization conditions indicate that epitope I is located on the outer side of the sporozoite surface membrane whereas epitope CTR is located on the inner side, together providing experimental evidence that EtMIC1 is a transmembrane protein. IFA also labeled the EtMIC1 protein on the parasitophorous vacuole membrane and on the surface of schizonts, which suggests that the EtMIC1 protein may play an important role in parasitophorous vacuole formation and E. tenella development. Immunoprotective efficacy experiments revealed that epitope I has good immunogenicity, as evidenced by its induction of high serum antibody levels, blood lymphocyte proliferation, and CD4+ blood lymphocyte percentage.

Förster Resonance Energy Transfer-Based Fluorescent Probe for the Selective Imaging of Hydroxylamine in Living Cells.

Hydroxylamine (HA) is an important product of cell metabolism and plays a significant role in many biological processes, and therefore, real-time imaging of HA is of great importance for the in-depth study of its physiological and pathological functions. However, a HA-specific fluorescent probe is currently lacking primarily because the highly selective HA-responsive site is undeveloped. To address this critical issue, we present a HA-specific FRET-based fluorescent probe (RhChr) for the selective detection of HA in living systems. Inspired by aza-Michael addition, the unsaturated system appended with an iminium ion was employed as the new HA-specific response site. In response to HA, RhChr provided a ratiometric signal output with excellent selectivity toward HA over biothiols and ammonia. We have demonstrated that RhChr could be applied for the ratiometric imaging of endogenous HA in living cells and the evaluation of xanthine oxidase (XOD) activity in living organs.

Ratiometric Imaging of Cysteine Level Changes in Endoplasmic Reticulum during H2O2-Induced Redox Imbalance.

Cysteine (Cys) is an important mediator to regulate the redox state of endoplasmic reticulum (ER), and its level is closely related with many ER stress induced serious diseases. Herein, we present an ER-specific fluorescent probe for the ratiometric imaging of cellular Cys for the first time. The probe exhibited desirable selectivity and sensitivity to Cys. Biological imaging experiments demonstrated that the probe possessed an ER-targeting property, showed ratiometric response to Cys in ER, and could be applied for the ratiometric imaging of Cys level changes during H2O2-induced redox imbalance in living cells.

A near-infrared and two-photon dual-mode fluorescent probe for the colorimetric monitoring of SO2in vitro and in vivo.

SO2 has been recently identified as an essential gas messenger followed by NO, CO and H2S. However, abnormal concentrations of SO2 in our bodies can cause many diseases. Thus, the real-time monitoring of SO2 to well define the generation, physiological and pathological functions of SO2 is urgently needed. In this work, we developed a novel SO2 fluorescent probe on the basis of the conjugation of semi-cyanine and coumarin derivate dyes with superior features, such as near-infrared (NIR) and two-photon dual-mode monitoring, a large Stokes shift (175 nm), ultrafast response towards SO2 (within 10 s), high selectivity and photostability. Furthermore, this probe could sense SO2 by dual colorimetric and fluorescence means. In biological imaging, the probe was able to trace exogenous and endogenous SO2 in living cells, mitochondria, E. coli, zebrafish and mice under an NIR and two-photon dual-mode. These results demonstrated that the probe has strong potential for studying the physiological and pathological functions of SO2in vitro and in vivo.

The ubiquitin receptors DA1, DAR1, and DAR2 redundantly regulate endoreduplication by modulating the stability of TCP14/15 in Arabidopsis.

Organ growth involves the coordination of cell proliferation and cell growth with differentiation. Endoreduplication is correlated with the onset of cell differentiation and with cell and organ size, but little is known about the molecular mechanisms linking cell and organ growth with endoreduplication. We have previously demonstrated that the ubiquitin receptor DA1 influences organ growth by restricting cell proliferation. Here, we show that DA1 and its close family members DAR1 and DAR2 are redundantly required for endoreduplication during leaf development. DA1, DAR1, and DAR2 physically interact with the transcription factors TCP14 and TCP15, which repress endoreduplication by directly regulating the expression of cell-cycle genes. We also show that DA1, DAR1, and DAR2 modulate the stability of TCP14 and TCP15 proteins in Arabidopsis thaliana. Genetic analyses demonstrate that DA1, DAR1, and DAR2 function in a common pathway with TCP14/15 to regulate endoreduplication. Thus, our findings define an important genetic and molecular mechanism involving the ubiquitin receptors DA1, DAR1, and DAR2 and the transcription factors TCP14 and TCP15 that links endoreduplication with cell and organ growth.

Targeting HIF-1α alleviates the inflammatory responses and rebuilds the CD4+ T cell subsets balance in the experimental autoimmune myasthenia gravis inflammation model via regulating cellular and humoral immunity.

BACKGROUND: Cells and tissues in an inflammatory state are usually hypoxic. The hypoxic environment can affect the differentiation of immune cells and produce Hypoxia-inducible Factor-1α (HIF-1α). Inflammation is also a major contributor to the development and deterioration of Myasthenia Gravis (MG). There are limited studies on the immunopathological mechanism and targeted therapy associated with MG exacerbated with inflammation. This research aimed to explore whether BAY 87-2243 (HIF-1α inhibitor) ameliorates the symptoms of the Experimental Autoimmune Myasthenia Gravis (EAMG) inflammation model and study its regulatory mechanism on cellular immunity and humoral immunity. METHODS: We first establish the EAMG inflammation model using Lipopolysaccharide (LPS), BAY 87-2243 was applied to the EAMG inflammation model and its therapeutic effects were evaluated in vivo and in vitro experiments. RESULTS: The proportion of Treg cells was increased whereas Th1, Th17, and Th1/17 cells were decreased in BAY 87-2243-treated EAMG inflammation model. BAY 87-2243 ameliorated the acetylcholine receptors (AChRs) loss and the complement deposited at the neuromuscular junction of the EAMG inflammation model, declined the levels of IFN-γ, IL-17, and IL-6 in serum, and further attenuated responses in the germinal center and reduced the antibody levels by inhibiting the IL-6-dependent STAT3 axis. CONCLUSION: BAY 87-2243 restored the balance of CD4+T cell subsets and reduced the production of the pro-inflammatory cytokines, thus acting as both an immune imbalance regulator and anti-inflammatory. The current study suggests that HIF-1α might be a potential target for the treatment of MG exacerbated with inflammation.

Enhanced microwave absorption performance of Fe3Al flakes by optimizing the carbon nanotube coatings.

Fe3Al is a good magnetic loss absorber for microwave absorption. However, due to the relatively high density and poor impedance matching ratio, the potential of Fe3Al cannot be fully released. Herein, a dielectric loss absorber of carbon nanotubes (CNTs) is coupled with Fe3Al to form Fe3Al/CNTs composite absorbers. CNTs are randomly tangled and coated on the surface of the Fe3Al flakes, forming a connecting conductive network. By carefully tuning the content of CNTs, the optimized Fe3Al/CNTs composite absorber with 1.5% of CNTs can combine both magnetic loss and dielectric loss mechanisms, thus achieving an impedance matching ratio close to 1 while keeping strong attenuation for enhanced microwave absorption. As a result, an effective absorption bandwidth (RL ≤ -10 dB) of 4.73 GHz at a thickness of 2 mm is achieved.

The BTB-ZF gene Bm-mamo regulates pigmentation in silkworm caterpillars.

The color pattern of insects is one of the most diverse adaptive evolutionary phenotypes. However, the molecular regulation of this color pattern is not fully understood. In this study, we found that the transcription factor Bm-mamo is responsible for black dilute (bd) allele mutations in the silkworm. Bm-mamo belongs to the BTB zinc finger family and is orthologous to mamo in Drosophila melanogaster. This gene has a conserved function in gamete production in Drosophila and silkworms and has evolved a pleiotropic function in the regulation of color patterns in caterpillars. Using RNAi and clustered regularly interspaced short palindromic repeats (CRISPR) technology, we showed that Bm-mamo is a repressor of dark melanin patterns in the larval epidermis. Using in vitro binding assays and gene expression profiling in wild-type and mutant larvae, we also showed that Bm-mamo likely regulates the expression of related pigment synthesis and cuticular protein genes in a coordinated manner to mediate its role in color pattern formation. This mechanism is consistent with the dual role of this transcription factor in regulating both the structure and shape of the cuticle and the pigments that are embedded within it. This study provides new insight into the regulation of color patterns as well as into the construction of more complex epidermal features in some insects.

Clinical evaluation of efficacy of leflunomide combined with low-dose prednisone for treatment of myasthenia gravis.

This study evaluated the clinical efficacy of leflunomide combined with low-dose prednisone (0.25 mg/kg/day) for treatment of myasthenia gravis (MG). We enrolled 32 MG patients treated with leflunomide combined with low-dose prednisone. In the control group, 14 patients were treated with low-dose prednisone. Improvement in MG composite (MGC) score of ≥ 3 points from enrollment to 12-week follow-up indicated that the treatment was effective. In the leflunomide combined low-dose prednisone group, the median of MGC score at the time of enrollment was 8.5 points. After 12 weeks, the MGC score dropped to four points. There was statistically significant difference in MGC score before and after treatment (p < 0.001). In the low-dose prednisone group also followed up for 12 weeks, the median of MGC score of the patients decreased from 7 to 4 points, and the change was not statistically significant (p = 0.05). In the leflunomide combined low-dose prednisone group, the improvement of clinical symptoms occurred mainly in the first 4 weeks and the last 4 weeks. Relatively, the decline of the score was mostly seen during the first 8 weeks in the low-dose prednisone group. In leflunomide combined with low-dose prednisone group, the effective rate of generalized MG(gMG) was significantly higher than ocular MG(oMG) (χ2 test, p = 0.036). However, there is no significant difference in the effective rate between AChR-Ab-positive and -negative groups (Fisher's Exact Test, p = 0.625). No serious side effects were observed in any of the subjects. Leflunomide combined with low-dose prednisone rapidly improved the clinical symptoms of patients with MG. It may be a promising treatment for gMG.

JAK2 inhibitor ameliorates the progression of experimental autoimmune myasthenia gravis and balances Th17/Treg cells via regulating the JAK2/STAT3-AKT/mTOR signaling pathway.

BACKGROUND: An imbalance in Th17/regulatory T (Treg) cells is the major pathogenic mechanism underlying myasthenia gravis (MG). JAK2 inhibitors selectively inhibit JAK2 and reduce inflammatory responses. However, there have been no studies examining the therapeutic effects of JAK2 inhibitors in the context of MG. METHODS: Here, an experimental autoimmune MG (EAMG) rat model was established to explore the therapeutic effect of JAK2 inhibitors on EAMG rats immunized with the AChR α-subunit (97-116 peptide). A JAK2 inhibitor was administered to EAMG rats both in vivo and in vitro. The following experimental methods were used to evaluate the effects of JAK2 inhibitors. The behavioral scores and body weights of the rats were assessed on alternate days. Serum anti-AChR (97-116) IgG and cytokine levels were detected using ELISA. CD4+ T cell subsets and related transcription factors in mononuclear cells were detected using flow cytometry and qPCR, respectively. The expression levels of protein molecules in the signaling pathway were detected by western blotting, and the neuromuscular junctions were observed using immunofluorescence. RESULTS: The results revealed that JAK2 inhibitors could regulate Th17/Treg balance in vivo and in vitro. JAK2 inhibitors reduced the immune response in EAMG rats (including reducing pro-inflammatory cytokines and postsynaptic membrane complement deposition), improved clinical symptoms, and increased AChR aggregation in the postsynaptic membrane. Meanwhile, this study demonstrated that JAK2 inhibitor treatment suppressed the phosphorylation of JAK2/STAT3 and AKT/mTOR pathways and decreased the expression level of the IL-23 receptor. CONCLUSIONS: This study reveals that there is crosstalk between the JAK2/STAT3 and AKT/mTOR pathways in EAMG rats. JAK2 inhibitors can ameliorate EAMG by regulating Th17/Treg balance by inhibiting both signaling pathways. Our study provides new potential therapeutic targets for MG immunotherapy.

Photosensitizers with aggregation-induced far-red/near-infrared emission for versatile visualization and broad-spectrum photodynamic killing of pathogenic microbes.

The exploration of photosensitizers with aggregation-induced emission (AIE PSs) for efficient visualization and broad-spectrum photodynamic killing of pathogenic microbes is a significant task. Herein, two far-red/near-infrared AIE-active PSs (TBTPy and TBTCy) were attained to show efficient Type I and Type II ROS generation, benefiting from the efficient ISC processes. The attained AIE PSs, especially TBTPy with bright emission, showed advantages in discriminating G+ bacteria over G- bacteria, and distinguishing dead E. coli from lived one. Both TBTPy and TBTCy have the capacity of broad-spectrum photodynamic killing of pathogenic microbes in vitro with considerable safety for mammalian cells. Antimicrobial mechanism is found to be changing osmotic pressure of cytoplasm in E. coli, causing cell deformation and destruction of S. aureus and C. albicans. In vivo anti-infection experiment demonstrated AIE PSs can accelerate the healing process of the burned wounds on rats infected by methicillin-resistant S. aureus (MRSA) or E. coli, indicating their potential to treat tertiary burns in clinical application. Therefore, the attained AIE PSs hold great promise as antimicrobial candidates in infective therapeutic application.