Rice false smut virulence protein subverts host chitin perception and signaling at lemma and palea for floral infection.

The flower-infecting fungus Ustilaginoidea virens causes rice false smut, which is a severe emerging disease threatening rice (Oryza sativa) production worldwide. False smut not only reduces yield, but more importantly produces toxins on grains, posing a great threat to food safety. U. virens invades spikelets via the gap between the 2 bracts (lemma and palea) enclosing the floret and specifically infects the stamen and pistil. Molecular mechanisms for the U. virens-rice interaction are largely unknown. Here, we demonstrate that rice flowers predominantly employ chitin-triggered immunity against U. virens in the lemma and palea, rather than in the stamen and pistil. We identify a crucial U. virens virulence factor, named UvGH18.1, which carries glycoside hydrolase activity. Mechanistically, UvGH18.1 functions by binding to and hydrolyzing immune elicitor chitin and interacting with the chitin receptor CHITIN ELICITOR BINDING PROTEIN (OsCEBiP) and co-receptor CHITIN ELICITOR RECEPTOR KINASE1 (OsCERK1) to impair their chitin-induced dimerization, suppressing host immunity exerted at the lemma and palea for gaining access to the stamen and pistil. Conversely, pretreatment on spikelets with chitin induces a defense response in the lemma and palea, promoting resistance against U. virens. Collectively, our data uncover a mechanism for a U. virens virulence factor and the critical location of the host-pathogen interaction in flowers and provide a potential strategy to control rice false smut disease.

MADS-box protein PpDAM6 regulates chilling requirement-mediated dormancy and bud break in peach.

Bud dormancy is crucial for winter survival and is characterized by the inability of the bud meristem to respond to growth-promotive signals before the chilling requirement (CR) is met. However, our understanding of the genetic mechanism regulating CR and bud dormancy remains limited. This study identified PpDAM6 (DORMANCY-ASSOCIATED MADS-box) as a key gene for CR using a genome-wide association study analysis based on structural variations in 345 peach (Prunus persica (L.) Batsch) accessions. The function of PpDAM6 in CR regulation was demonstrated by transiently silencing the gene in peach buds and stably overexpressing the gene in transgenic apple (Malus × domestica) plants. The results showed an evolutionarily conserved function of PpDAM6 in regulating bud dormancy release, followed by vegetative growth and flowering, in peach and apple. The 30-bp deletion in the PpDAM6 promoter was substantially associated with reducing PpDAM6 expression in low-CR accessions. A PCR marker based on the 30-bp indel was developed to distinguish peach plants with non-low and low CR. Modification of the H3K27me3 marker at the PpDAM6 locus showed no apparent change across the dormancy process in low- and non-low- CR cultivars. Additionally, H3K27me3 modification occurred earlier in low-CR cultivars on a genome-wide scale. PpDAM6 could mediate cell-cell communication by inducing the expression of the downstream genes PpNCED1 (9-cis-epoxycarotenoid dioxygenase 1), encoding a key enzyme for ABA biosynthesis, and CALS (CALLOSE SYNTHASE), encoding callose synthase. We shed light on a gene regulatory network formed by PpDAM6-containing complexes that mediate CR underlying dormancy and bud break in peach. A better understanding of the genetic basis for natural variations of CR can help breeders develop cultivars with different CR for growing in different geographical regions.

Haplotype-resolved genome of a heterozygous wild peach reveals the PdaWRKY4-PdaCYP716A1 module mediates resistance to aphids by regulating betulin biosynthesis.

Wild species of domesticated crops provide valuable genetic resources for resistance breeding. Prunus davidiana, a wild relative of peach with high heterozygosity and diverse stress tolerance, exhibits high resistance against aphids. However, the highly heterozygous genome of P. davidiana makes determining the underlying factors influencing resistance traits challenging. Here, we present the 501.7 Mb haplotype-resolved genome assembly of P. davidiana. Genomic comparisons of the two haplotypes revealed 18,152 structural variations, 2,699 Pda_hap1-specific and 2,702 Pda_hap2-specific genes, and 1,118 allele-specific expressed genes. Genome composition indicated 4.1% of the P. davidiana genome was non-peach origin, out of which 94.5% was derived from almond. Based on the haplotype genome, the aphid resistance quantitative trait locus (QTL) was mapped at the end of Pda03. From the aphid resistance QTL, PdaWRKY4 was identified as the major dominant gene, with a 9-bp deletion in its promoter of the resistant phenotype. Specifically, PdaWRKY4 regulates aphid resistance by promoting PdaCYP716A1-mediated anti-aphid metabolite betulin biosynthesis. Moreover, we employed a genome design to develop a breeding workflow for rapidly and precisely producing aphid-resistant peaches. In conclusion, this study identifies a novel aphid resistance gene and provides insights into genome design for the development of resistant fruit cultivars.

CEBoosting: Online sparse identification of dynamical systems with regime switching by causation entropy boosting.

Regime switching is ubiquitous in many complex dynamical systems with multiscale features, chaotic behavior, and extreme events. In this paper, a causation entropy boosting (CEBoosting) strategy is developed to facilitate the detection of regime switching and the discovery of the dynamics associated with the new regime via online model identification. The causation entropy, which can be efficiently calculated, provides a logic value of each candidate function in a pre-determined library. The reversal of one or a few such causation entropy indicators associated with the model calibrated for the current regime implies the detection of regime switching. Despite the short length of each batch formed by the sequential data, the accumulated value of causation entropy corresponding to a sequence of data batches leads to a robust indicator. With the detected rectification of the model structure, the subsequent parameter estimation becomes a quadratic optimization problem, which is solved using closed analytic formulas. Using the Lorenz 96 model, it is shown that the causation entropy indicator can be efficiently calculated, and the method applies to moderately large dimensional systems. The CEBoosting algorithm is also adaptive to the situation with partial observations. It is shown via a stochastic parameterized model that the CEBoosting strategy can be combined with data assimilation to identify regime switching triggered by the unobserved latent processes. In addition, the CEBoosting method is applied to a nonlinear paradigm model for topographic mean flow interaction, demonstrating the online detection of regime switching in the presence of strong intermittency and extreme events.

Comprehensive plasma metabolomics and lipidomics of benign and malignant solitary pulmonary nodules.

INTRODUCTION: Solitary pulmonary nodules (SPNs) are commonly found in imaging technologies, but are plagued by high false-positive rates. OBJECTIVE: We aimed to identify metabolic alterations in SPN etiology and diagnosis using less invasive plasma metabolomics and lipidomics. METHODS: In total, 1160 plasma samples were obtained from healthy volunteers (n = 280), benign SPNs (n = 157) and malignant SPNs (stage I, n = 723) patients enrolled from 5 independent centers. Gas chromatography-triple quadrupole mass spectrometry (GC‒MS) and liquid chromatography-Q Exactive Hybrid Quadrupole-Orbitrap mass spectrometry (LC‒MS) were used to analyze the samples for untargeted metabolomics and lipidomics. RESULTS AND CONCLUSION: GC‒MS-based metabolomics revealed 1336 metabolic features, while LC‒MS-based lipidomics revealed 6088 and 2542 lipid features in the positive and negative ion modes, respectively. The metabolic and lipidic characteristics of healthy vs. benign or malignant SPNs exhibited substantial pattern differences. Of note, benign and malignant SPNs had no significant variations in circulating metabolic and lipidic markers and were validated in four other centers. This study demonstrates evidence of early metabolic alterations that can possibly distinguish SPNs from healthy controls, but not between benign and malignant SPNs.

The false smut pathogen Ustilaginoidea virens requires rice stamens for false smut ball formation.

Rice false smut has emerged as a serious grain disease in rice production worldwide. The disease is characterized by the transformation of individual rice florets into false smut balls, which is caused by the fungal pathogen Ustilaginoidea virens. To date, little is known about the host factors required for false smut ball formation by U. virens. In this study, we identified histological determinants for the formation of false smut balls by inoculating U. virens into rice floral mutants defective with respect to individual floral parts. The results showed that U. virens could form mature false smut balls in rice floral mutants with defective pistils, but failed to develop false smut balls in the superwoman mutant lacking stamens, identifying that U. virens requires rice stamens to complete its infection cycle. Comparative transcriptome analysis indicated a list of candidate host genes that may facilitate nutrient acquisition by U. virens from the rice stamens, such as SWEET11, SWEET14 and SUT5, and genes involved in the biosynthesis of trehalose and raffinose family sugars. These data pinpoint rice stamens as the key target organ of U. virens infection and provide a valuable starting point for dissecting the molecular mechanism of false smut ball formation.

Tumor Targeting Synergistic Drug Delivery by Self-Assembled Hybrid Nanovesicles to Overcome Drug Resistance.

PURPOSE: To overcome multi-drug resistance (MDR) in tumor chemotherapy, a polymer/inorganic hybrid drug delivery platform with tumor targeting property and enhanced cell uptake efficiency was developed. METHOD: To evaluate the applicability of our delivery platform for the delivery of different drug resistance inhibitors, two kinds of dual-drug pairs (doxorubicin/buthionine sulfoximine and doxorubicin/tariquidar, respectively) were loaded in heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles to realize simultaneous delivery of an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells. RESULTS: Prepared by self-assembly, the drug loaded hybrid nanovesicles with a mean size less than 210 nm and a negative zeta potential exhibit good stability in serum contained aqueous media. The in vitro cytotoxicity evaluation indicates that hybrid nanovesicles with tumor targeting biotin moieties have an enhanced tumor cell inhibitory effect. In addition, dual-drug loaded hybrid nanovesicles exhibit significantly stronger cell growth inhibition as compared with doxorubicin (DOX) mono-drug loaded nanovesicles due to the reduced intracellular glutathione (GSH) content by buthionine sulfoximine (BSO) or the P-glycoprotein (P-gp) inhibition by tariquidar (TQR). CONCLUSIONS: The tumor targeting nanovesicles prepared in this study, which can simultaneously deliver multiple drugs and effectively reverse drug resistance, have promising applications in drug delivery for tumor treatments. The polymer/inorganic hybrid drug delivery platform developed in this study has good applicability for the co-delivery of different anti-tumor drug/drug resistance inhibitor pairs to overcome MDR. Graphical Abstract A polymer/inorganic hybrid drug delivery platform with enhanced cell uptake was developed for tumor targeting synergistic drug delivery. The heparin-biotin/heparin/protamine sulfate/calcium carbonate nanovesicles prepared in this study can deliver an anticancer drug and a drug resistance inhibitor into drug-resistant tumor cells simultaneously to overcome drug resistance efficiently.

[Protective effect of synthetic salidroside on acute lung injury in rats].

To study the protective effect and mechanism of synthetic salidroside on acute lung injury (ALI) induced by lipopolysaccharide (LPS), male Sprague-Dawley (SD) rats were randomly divided into saline control group, 3 mg/kg LPS model group, different doses of salidroside groups (5, 20 and 80 mg/kg), and 5 mg/kg dexamethasone group. Intratracheal LPS instillation was used to establish the ALI model 0.5 h after intraperitoneal injection of salidroside or dexamethasone, and the rats were sacrificed 6 h later. Lung wet/dry weight ratio (W/D) was calculated. Lung tissue pathology and lung injury score (LIS) were observed and evaluated through hematoxylin and eosin (HE) staining. The centrifugal sediment of bronchoalveolar lavage fluid (BALF) was used to count the polymorphonuclear leukocyte (PMN) number by Wright's staining, and the centrifugal supernatant of BALF was used to determine the contents of protein and inflammatory factors (TNF-α, IL-1ß and IL-6). The contents of myeloperoxidase (MPO) and malondialdehyde (MDA) in lung tissue were determined. Western blot was used to detect the expression levels of phosphorylated and total nuclear factor kappa B (NF-κB)/p65 protein in lung tissue. The results showed that, compared with LPS group, the intervention of synthetic salidroside alleviated the pathological damage in lung tissue, decreased the LIS and lung W/D ratio (P < 0.05), reduced the PMN number, the contents of protein and inflammatory factors in BALF (P < 0.05), reduced the contents of MPO and MDA in lung tissue (P < 0.05), and inhibited the expression of p-NF-κB in lung tissue (P < 0.05). The results suggest that synthetic salidroside has a protective effect on ALI induced by LPS, and its mechanism is related to inhibiting the phosphorylation of NF-κB and reducing the aggregation of PMN in the lung.

Self-assembled polymer/inorganic hybrid nanovesicles for multiple drug delivery to overcome drug resistance in cancer chemotherapy.

With the aim to develop a facile strategy to prepare functional drug carriers to overcome multidrug resistance (MDR), we prepared heparin/protamine/calcium carbonate (HP/PS/CaCO3) hybrid nanovesicles with enhanced cell internalization, good serum stability, and pH sensitivity for drug delivery. All the functional components including protamine to improve the cell uptake, heparin to enhance the stability, and CaCO3 to improve drug loading and endow the system with pH sensitivity were introduced to the nanovesicles by self-assembly in an aqueous medium. An antitumor drug (doxorubicin, DOX) and a drug resistance inhibitor (tariquidar, TQR) were coloaded in the nanovesicles during self-assembly preparation of the nanovesicles. The drug loaded nanovesicles, which had a mean size less than 200 nm, exhibited a pH-sensitive drug release behavior. In vitro study was carried out in both nonresistant cells (HeLa and MCF-7) and drug-resistant cancer cells (MCF-7/ADR). Because of the enhanced intracellular and nuclear drug accumulation through effective inhibition of the P-gp efflux transporter, DOX/TQR coloaded nanovesicles showed significantly improved tumor cell inhibitory efficiency, especially for drug-resistant cells. These results suggest the self-assembled nanovesicles have promising applications in multidrug delivery to overcome drug resistance in tumor treatments.

[Association between gene polymorphism of CD40 gene and coronary artery lesion in Kawasaki disease].

OBJECTIVE: To study the association between two single nucleotide polymorphisms (rs4810485 and rs1535045 in CD40 gene) and Kawasaki disease (KD) in Han Chinese children. METHODS: A case-control study was performed on 184 children with KD and 206 normal controls. The polymorphisms of two SNPs in CD40 gene were detected using PCR-RFLP. RESULTS: There were no significant differences in the genotype distribution and allele frequency of SNP rs4810485 in CD40 gene between the KD and normal groups (P>0.05). The genotype distribution of SNP rs1535045 in CD40 gene in the KD group was significantly different from the control group (P<0.05). T allele of SNP rs1535045 was shown as a risk factor for development of KD (OR=1.592, 95%CI: 1.182-2.144, P=0.004). There were no association between the polymorphisms of the two SNPs and coronary artery lesions (P>0.05). CONCLUSIONS: SNP rs1535045 may be associated with the development of KD in Han Chinese children, while SNP rs4810485 may not.

(1S,3aS,4S,7aS)-Ethyl 1-benzyl-2-(4-meth-oxy-benz-yl)-6,7-dimethyl-3-oxo-2,3,3a,4,5,7a-hexa-hydro-1H-isoindole-4-carboxyl-ate dichloro-methane monosolvate.

In the title compound, C(28)H(33)NO(4)·CH(2)Cl(2), the pyrrolidone ring adopts a twisted envelope conformation and the cyclo-hexene has a half-chair conformation. In the crystal, weak C-H⋯O hydrogen bonds link the components into chains along [100].

2-(2-Chloro-phen-yl)-N-cyclo-hexyl-2-oxoacetamide.

In the title compound, C14H16ClNO2, the cyclo-hexyl ring has a chair conformation. The dihedral angle between the benzene ring and the mean plane of the four planar C atoms of the cyclo-hexyl ring is 45.2 (3)°. The two carbonyl groups are trans to one another, with an O=C-C=O torsion angle of -137.1 (3)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds forming chains propagating along [001]. A region of disordered electron density, situated near the unit-cell corners, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. It gave a solvent-accessible void of ca 400 Å(3) for only 21 electrons. It is probably due to traces of the solvent of crystallization and was not taken into account during structure refinement.

Fibronectin promotes tumor progression through integrin αvß3/PI3K/AKT/SOX2 signaling in non-small cell lung cancer.

The tumor microenvironment, especially the extracellular matrix (ECM), is strongly associated with tumor cell proliferation and metastasis. Numerous studies have provided evidence suggesting that fibronectin (FN) in ECM supports cancer cell escape and contributes to cell migration, resulting in distant cancer metastasis and poor outcomes in patients. In our study, it was demonstrated that FN expression was elevated in tumor tissues from highly malignant NSCLC patients, compared to those with low malignancy (p = 0.0076). Importantly, FN promoted proliferative phenotypes and strengthened tumorigenesis capabilities in NSCLC cells, including A549 and Lewis cells, leading to sustained tumor growth in vivo. Mechanistically, it was identified that FN facilitated the activation of the integrin αvß3/PI3K/AKT signaling pathway, which subsequently upregulated tumor stemness through the downstream transcription factor SOX2. Blockade of integrin αvß3 signal efficiently suppressed NSCLC proliferation and tumorigenesis both in vitro and in vivo. In conclusion, our study demonstrated that extracellular FN could facilitate NSCLC development through the integrin αvß3/PI3K/AKT/SOX2 signaling pathway. Blockade of integrin αvß3 could efficiently enhance the anticancer effects of chemotherapy, offering an innovative approach for clinical NSCLC therapy.

A natural allele of proteasome maturation factor improves rice resistance to multiple pathogens.

Crops with broad-spectrum resistance loci are highly desirable in agricultural production because these loci often confer resistance to most races of a pathogen or multiple pathogen species. Here we discover a natural allele of proteasome maturation factor in rice, UMP1R2115, that confers broad-spectrum resistance to Magnaporthe oryzae, Rhizoctonia solani, Ustilaginoidea virens and Xanthomonas oryzae pv. oryzae. Mechanistically, this allele increases proteasome abundance and activity to promote the degradation of reactive oxygen species-scavenging enzymes including peroxidase and catalase upon pathogen infection, leading to elevation of H2O2 accumulation for defence. In contrast, inhibition of proteasome function or overexpression of peroxidase/catalase-encoding genes compromises UMP1R2115-mediated resistance. More importantly, introduction of UMP1R2115 into a disease-susceptible rice variety does not penalize grain yield while promoting disease resistance. Our work thus uncovers a broad-spectrum resistance pathway integrating de-repression of plant immunity and provides a valuable genetic resource for breeding high-yield rice with multi-disease resistance.

Decreased expression of C-erbB-2 and CXCR4 in breast cancer after primary chemotherapy.

BACKGROUND: Biological molecular markers such as proto-oncogene erbB-2 (HER-2/neu, c-erbB-2), the CXC chemokine receptor 4 (CXCR4), estrogen receptor (ER), Proliferating Cell Nuclear Antigen (PCNA), DNA topoisomerase II (topo II), P-glycoprotein (P-gp) and glutathione S-transferase (GST) were observed for changes after administration of neochemotherapy and whether these protein expression changes were correlated with response to chemotherapy. METHODS: Sixty-four patients with primary breast cancer who had undergone neo-adjuvant chemotherapy were enrolled in the present study. The expressions of C-erbB-2, CXCR4 and ER-α were measured by immunohistochemistry (IHC) on full tissue sections and on tissue microarrays (TMAs). PCNA, TopoII, P-gp and GST were measured by IHC on TMAs. On the other hand, CXCR4, C-erbB-2 and ER-α expressions were detected using western blot analysis to 16 pairs of fresh preoperative core biopsies. The final surgical specimens were obtained from patients with breast carcinoma who received neo-adjuvant chemotherapy and obtained a partial response (PR). RESULTS: Our data demonstrated that the levels of C-erbB-2, CXCR4 and ER-α in patients decreased after they received neo-adjuvant chemotherapy on full tissue sections and on TMAs. The PCNA level was down-regulated after receiving neo-adjuvant chemotherapy, and no significant change was observed for TopoII, P-gp and GST. The levels of C-erbB-2, CXCR4 and ER-α were also down-regulated after neo-adjuvant chemotherapy was administered, as detected by western blot. In addition, the change expressions of C-erbB-2 and CXCR4 in specimens tended to be correlated with pathological change to neo-adjuvant chemotherapy on full tissue sections and on TMAs in a Pearson chi-square analysis. CONCLUSIONS: As demonstrated in our study, after breast cancer patients were treated with neo-adjuvant systemic therapy, decreased expressions of C-erbB2, ER-α and CXCR4 were observed. Down-regulated expressions of c-erbB-2 and CXCR4 may be a novel mechanism of chemotherapy; the changes of these objective markers may be useful in evaluating the clinical response of neo-adjuvant chemotherapy in breast cancer.

rac-7-[(2E)-But-2-eno-yl]-13-chloro-N-cyclo-hexyl-7,8-dihydro-5H-isochromeno[4,3-c]phenanthridine-8-carboxamide.

In the title compound, C(31)H(29)ClN(2)O(3), the two heterocyclic rings, belonging to a system of five condensed rings, adopt conformations intermediate between twist-boat and sofa. The secondary amide group is involved in a weak intramolecular N-H⋯N hydrogen bond. In the crystal, molecules are linked by pairs of C-H⋯Cl hydrogen bonds to form inversion dimers. These dimers are linked via a C-H⋯O interaction to form chains propagating along the b-axis direction.

N-Cyclo-hexyl-2-oxo-2-phenyl-acetamide.

In the title compound, C(14)H(17)NO(2), the two carbonyl groups are oriented with respect to each other with a torsion angle of -129.9 (3)°. The cyclo-hexane ring adopts a chair conformation. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds into a chain running along the a axis.

Ethyl 4-methyl-1,3-dioxo-1,2,3,4-tetra-hydro-isoquinoline-4-carboxyl-ate.

In the title compound, C(13)H(13)NO(4), the fused-ring system is nearly planar, with an r.m.s. deviation of 0.0408 Å. In the crystal, mol-ecules are linked into centrosymmetric dimers by a pair of N-H⋯O hydrogen bonds. The ethyl group is disordered over two positions in a ratio of 0.758 (6):0.242 (6).

Overproduction of OsRACK1A, an effector-targeted scaffold protein promoting OsRBOHB-mediated ROS production, confers rice floral resistance to false smut disease without yield penalty.

Grain formation is fundamental for crop yield but is vulnerable to abiotic and biotic stresses. Rice grain production is threatened by the false smut fungus Ustilaginoidea virens, which specifically infects rice floral organs, disrupting fertilization and seed formation. However, little is known about the molecular mechanisms of the U. virens-rice interaction and the genetic basis of floral resistance. Here, we report that U. virens secretes a cytoplasmic effector, UvCBP1, to facilitate infection of rice flowers. Mechanistically, UvCBP1 interacts with the rice scaffold protein OsRACK1A and competes its interaction with the reduced nicotinamide adenine dinucleotide phosphate oxidase OsRBOHB, leading to inhibition of reactive oxygen species (ROS) production. Although the analysis of natural variation revealed no OsRACK1A variants that could avoid being targeted by UvCBP1, expression levels of OsRACK1A are correlated with field resistance against U. virens in rice germplasm. Overproduction of OsRACK1A restores the OsRACK1A-OsRBOHB association and promotes OsRBOHB phosphorylation to enhance ROS production, conferring rice floral resistance to U. virens without yield penalty. Taken together, our findings reveal a new pathogenic mechanism mediated by an essential effector from a flower-specific pathogen and provide a valuable genetic resource for balancing disease resistance and crop yield.

2-(2-Chloro-phen-yl)-2-oxo-N-phenyl-acetamide.

In the title compound, C(14)H(10)ClNO(2), the dihedral angle between the two rings is 59.4 (2)°. The two carbonyl groups are oriented almost anti-periplanar to each other, with a torsion angle of -160.43 (2)°. In the crystal, mol-ecules are linked into inversion dimers by pairs of N-H⋯O hydrogen bonds.