Acclimation of intertidal macroalgae Ulva prolifera to UVB radiation: the important role of alternative oxidase.

BACKGROUND: Solar radiation is primarily composed of ultraviolet radiation (UVR, 200 - 400 nm) and photosynthetically active radiation (PAR, 400 - 700 nm). Ultraviolet-B (UVB) radiation accounts for only a small proportion of sunlight, and it is the primary cause of plant photodamage. The use of chlorofluorocarbons (CFCs) as refrigerants caused serious ozone depletion in the 1980s, and this had led to an increase in UVB. Although CFC emissions have significantly decreased in recent years, UVB radiation still remains at a high intensity. UVB radiation increase is an important factor that influences plant physiological processes. Ulva prolifera, a type of macroalga found in the intertidal zone, is intermittently exposed to UVB. Alternative oxidase (AOX) plays an important role in plants under stresses. This research examines the changes in AOX activity and the relationships among AOX, photosynthesis, and reactive oxygen species (ROS) homeostasis in U. prolifera under changes in UVB and photosynthetically active radiation (PAR). RESULTS: UVB was the main component of solar radiation impacting the typical intertidal green macroalgae U. prolifera. AOX was found to be important during the process of photosynthesis optimization of U. prolifera due to a synergistic effect with non-photochemical quenching (NPQ) under UVB radiation. AOX and glycolate oxidase (GO) worked together to achieve NADPH homeostasis to achieve photosynthesis optimization under changes in PAR + UVB. The synergism of AOX with superoxide dismutase (SOD) and catalase (CAT) was important during the process of ROS homeostasis under PAR + UVB. CONCLUSIONS: AOX plays an important role in the process of photosynthesis optimization and ROS homeostasis in U. prolifera under UVB radiation. This study provides further insights into the response of intertidal macroalgae to solar light changes.

COVPRIG robustly predicts the overall survival of IDH wild-type glioblastoma and highlights METTL1+ neural-progenitor-like tumor cell in driving unfavorable outcome.

BACKGROUND: Accurately predicting the outcome of isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) remains hitherto challenging. This study aims to Construct and Validate a Robust Prognostic Model for IDH wild-type GBM (COVPRIG) for the prediction of overall survival using a novel metric, gene-gene (G × G) interaction, and explore molecular and cellular underpinnings. METHODS: Univariate and multivariate Cox regression of four independent trans-ethnic cohorts containing a total of 800 samples. Prediction efficacy was comprehensively evaluated and compared with previous models by a systematic literature review. The molecular underpinnings of COVPRIG were elucidated by integrated analysis of bulk-tumor and single-cell based datasets. RESULTS: Using a Cox-ph model-based method, six of the 93,961 G × G interactions were screened to form an optimal combination which, together with age, comprised the COVPRIG model. COVPRIG was designed for RNA-seq and microarray, respectively, and effectively identified patients at high risk of mortality. The predictive performance of COVPRIG was satisfactory, with area under the curve (AUC) ranging from 0.56 (CGGA693, RNA-seq, 6-month survival) to 0.79 (TCGA RNAseq, 18-month survival), which can be further validated by decision curves. Nomograms were constructed for individual risk prediction for RNA-seq and microarray-based cohorts, respectively. Besides, the prognostic significance of COVPRIG was also validated in GBM including the IDH mutant samples. Notably, COVPRIG was comprehensively evaluated and externally validated, and a systemic review disclosed that COVPRIG outperformed current validated models with an integrated discrimination improvement (IDI) of 6-16%. Moreover, integrative bioinformatics analysis predicted an essential role of METTL1+ neural-progenitor-like (NPC-like) malignant cell in driving unfavorable outcome. CONCLUSION: This study provided a powerful tool for the outcome prediction for IDH wild-type GBM, and preliminary molecular underpinnings for future research.

Functional role of a novel zinc finger protein, AoZFA, in growth and kojic acid synthesis in Aspergillus oryzae.

Kojic acid (KA) is a valuable secondary metabolite that is regulated by zinc finger proteins in Aspergillus oryzae. However, only two such proteins have been characterized to function in kojic acid production of A. oryzae to date. In this study, we identified a novel zinc finger protein, AoZFA, required for kojic acid biosynthesis in A. oryzae. Our results showed that disruption of AozfA led to increased expression of kojA and kojR involved in kojic acid synthesis, resulting in enhanced kojic acid production, while overexpression of AozfA had the opposite effect. Furthermore, deletion of kojR in the AozfA disruption strain abolished kojic acid production, whereas overexpression of kojR enhanced it, indicating that AoZFA regulates kojic acid production by affecting kojR. Transcriptional activation assay revealed that AoZFA is a transcriptional activator. Interestingly, when kojR was overexpressed in the AozfA overexpression strain, the production of kojic acid failed to be rescued, suggesting that AozfA plays a distinct role from kojR in kojic acid biosynthesis. Moreover, we found that AozfA was highly induced by zinc during early growth stages, and its overexpression inhibited the growth promoted by zinc, whereas its deletion had no effect, suggesting that AoZFA is non-essential but has a role in the response of A. oryzae to zinc. Overall, these findings provide new insights into the roles of zinc finger proteins in the growth and kojic acid production of A. oryzae.IMPORTANCEKojic acid (KA) is an economically valuable secondary metabolite produced by Aspergillus oryzae due to its vast biological activities. Genetic modification of A. oryzae has emerged as an efficient strategy for enhancing kojic acid production, which is dependent on the mining of genes involved in kojic acid synthesis. In this study, we have characterized a novel zinc-finger protein, AoZFA, as a negative regulator of kojic acid production by affecting kojR. AozfA is an excellent target for improving kojic acid production without any effects on the growth of A. oryzae. Furthermore, the simultaneous modification of AozfA and kojR exerts a more significant promotional effect on kojic acid production than the modification of single genes. This study provides new insights for the regulatory mechanism of zinc finger proteins in the growth and kojic acid production of A. oryzae.

Remediation materials for the immobilization of hexavalent chromium in contaminated soil: Preparation, applications, and mechanisms.

Hexavalent chromium is a toxic metal that can induce severe chromium contamination of soil, posing a potential risk to human health and ecosystems. In recent years, the immobilization of Cr(VI) using remediation materials including inorganic materials, organic materials, microbial agents, and composites has exhibited great potential in remediating Cr(VI)-contaminated soil owing to the environmental-friendliness, short period, simple operation, low cost, applicability on an industrial scale, and high efficiency of these materials. Therefore, a systematical summary of the current progress on various remediation materials is essential. This work introduces the production (sources) of remediation materials and examines their characteristics in detail. Additionally, a critical summary of recent research on the utilization of remediation materials for the stabilization of Cr(VI) in the soil is provided, together with an evaluation of their remediation efficiencies toward Cr(VI). The influences of remediation material applications on soil physicochemical properties, microbial community structure, and plant growth are summarized. The immobilization mechanisms of remediation materials toward Cr(VI) in the soil are illuminated. Importantly, this study evaluates the feasibility of each remediation material application for Cr(VI) remediation. The latest knowledge on the development of remediation materials for the immobilization of Cr(VI) in the soil is also presented. Overall, this review will provide a reference for the development of remediation materials and their application in remediating Cr(VI)-contaminated soil.

Release of dissolved organic matter from wetland plants and its interaction with polycyclic aromatic hydrocarbons.

Dissolved organic matter (DOM) derived from wetland plants played a critical role in CWs pollutant migration. This study investigated the character and release pattern of DOM derived from two wetland plants, Phragmites australis and Cladophora sp., and the interaction between DOM with phenanthrene (PHE), benzo(a)pyrene (Bap), and benzo [k]fluoranthene (BkF) under different physical conditions were also studied using spectroscopic techniques. DOM release was related to plant species and withering stage. Humic acid (HA)-like fractions (C3 and C5) were dominated in P. australis (52%) and completely withered Cladophora sp. groups (55%), while protein-like fractions (C1 and C2) dominated in early withered Cladophora sp. groups (52%). Due to the cell and tissue structure difference among plants and their withering stage, DOM derived from early withered P. australis revealed a two-stage slow-fast phase, while other groups were linearly released (R2 0.87207-0.97091). A strong correlation existed between HA-like fractions and water quality index, reflecting the critical influence of plant decay in CWs operation performance. The analysis with Stern-Volmer equation indicated that plant-based DOM interacted with PAHs to form ground state complexes with possible involvement of π-π interaction, hydrogen bonding and cation bridging effect. Aromatic, molecular weight, and hydrophilicity of both DOM and PAHs affected their binding with the interaction capability in the order of BKF > Bap > PHE and C3 > C5 > C2 > C1 > C4. Besides, alkaline environment and high DO condition was highly unsuitable for the combination. Scientific management and appropriate operating condition were important in optimizing operation performance and controlling pollutant migration in CWs.

Transcriptome reveals the toxicity and genetic response of zebrafish to naphthenic acids and benzo[a]pyrene at ambient concentrations.

Naphthenic acids (NAs) are typical contaminants in heavily crude oil. Benzo[a]pyrene (B[a]P) is also a component of crude oil, but their combined effects have not been systematically explored. In this study, zebrafish (Danio rerio) were used as the test organisms, and behavioral indicators and enzyme activities were used as toxicity indicators. Combined with the effects of environmental concentrations, the toxic effects of low concentrations of commercially available NAs (0.5 mg/LNA) and benzo[a]pyrene (0.8 µg/LBaP) at single and compound exposures (0.5 mg/LNA and 0.8 µg/LBaP) were assayed in zebrafish, and transcriptome sequencing technology was used to explore the molecular mechanism of the two compounds affecting zebrafish from the molecular biology level. Sensitive molecular markers that could indicate the presence of contaminants were screened. The results showed that (1) zebrafish in the NA and BaP exposure groups exhibited increased locomotor behavior, and the mixed exposure group exhibited inhibition of locomotor behavior. Oxidative stress biomarkers showed increased activity under single exposure and decreased activity under the mixed exposure. (2) NA stress led to changes in the activity of transporters and the intensity of energy metabolism; BaP directly stimulates the pathway of actin production. When the two compounds are combined, the excitability of neurons in the central nervous system is decreased, and the actin-related genes are down-regulated. (3) After BaP and Mix treatments, genes were enriched in the cytokine-receptor interaction and actin signal pathway, while NA increased the toxic effect on the mixed treatment group. In general, the interaction between NA and BaP has a synergistic effect on the transcription of zebrafish nerve and motor behavior-related genes, resulting in increased toxicity under combined exposure. The changes in expression of various zebrafish genes are manifested in the changes in the normal movement behavior of zebrafish and the intensification of oxidative stress in the apparent behavior and physiological indicators. CAPSULE ABSTRACT: We investigated the toxicity and genetic alterations caused by NA, B[a]P, and their mixtures in zebrafish in an aquatic environment using transcriptome sequencing technology and comprehensive behavioral analysis. These changes involved energy metabolism, the generation of muscle cells, and the nervous system.

Phytophthora infection signals-induced translocation of NAC089 is required for endoplasmic reticulum stress response-mediated plant immunity.

Plants deploy various immune receptors to recognize pathogen-derived extracellular signals and subsequently activate the downstream defense response. Recently, increasing evidence indicates that the endoplasmic reticulum (ER) plays a part in the plant defense response, known as ER stress-mediated immunity (ERSI), that halts pathogen infection. However, the mechanism for the ER stress response to signals of pathogen infection remains unclear. Here, we characterized the ER stress response regulator NAC089, which was previously reported to positively regulate programed cell death (PCD), functioning as an ERSI regulator. NAC089 translocated from the ER to the nucleus via the Golgi in response to Phytophthora capsici culture filtrate (CF), which is a mixture of pathogen-associated molecular patterns (PAMPs). Plasma membrane localized co-receptor BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1 (BAK1) was required for the CF-mediated translocation of NAC089. The nuclear localization of NAC089, determined by the NAC domain, was essential for immune activation and PCD. Furthermore, NAC089 positively contributed to host resistance against the oomycete pathogen P. capsici and the bacteria pathogen Pseudomonas syringae pv. tomato (Pst) DC3000. We also proved that NAC089-mediated immunity is conserved in Nicotiana benthamiana. Together, we found that PAMP signaling induces the activation of ER stress in plants, and that NAC089 is required for ERSI and plant resistance against pathogens.

Ferroptosis induced by the biocontrol agent Pythium oligandrum enhances soybean resistance to Phytophthora sojae.

Ferroptosis is a newly discovered form of cell death accompanied by iron accumulation and lipid peroxidation. Both biotic and abiotic stresses can induce ferroptosis in plant cells. In the case of plant interactions with pathogenic Phytophthora oomycetes, the roles of ferroptosis are still largely unknown. Here, we performed transcriptome analysis on soybean plants treated with the biocontrol agent Pythium oligandrum, a soilborne and non-pathogenic oomycete capable of inducing plant resistance against Phytophthora sojae infection. Expression of homologous soybean genes involved in ferroptosis and resistance was reprogrammed upon P. oligandrum treatment. Typical hallmarks for characterizing ferroptosis were detected in soybean hypocotyl cells, including decreased glutathione (GSH) level, accumulation of ferric ions, and lipid peroxidation by reactive oxygen species (ROS). Meanwhile, ferroptosis-like cell death was triggered by P. oligandrum to suppress P. sojae infection in soybean. Protection provided by P. oligandrum could be attenuated by the ferroptosis inhibitor ferrostatin-1 (Fer-1), suggesting the critical role of ferroptosis in soybean resistance against P. sojae. Taken together, these results demonstrate that ferroptosis is a P. oligandrum-inducible defence mechanism against oomycete infection in soybean.

Force-Regulated State Transitions of Growing Axons.

Growing axons are one-dimensional active structures that are important for wiring the brain and repairing nerves. However, the biophysical mechanisms underlying the complex kinetics of growing axons remain elusive. Here, we develop a theoretical framework to recapitulate force-regulated states and their transitions in growing axons. We demonstrate a unique negative feedback mechanism that defines four distinct kinetic states in a growing axon, whose transitional boundaries depend on the interplay between cytoskeletal dynamics and axon-substrate adhesion. A phase diagram for axonal growth is formulated based on two dimensionless numbers.

Comparative Analyses of the Gut Microbiome of Two Fox Species, the Red Fox (Vulpes Vulpes) and Corsac Fox (Vulpes Corsac), that Occupy Different Ecological Niches.

The gut microbiome is integral for the host's living and environmental adaptation and crucially important for understanding host adaptive mechanisms. The red fox (Vulpes vulpes) dominates a wider ecological niche and more complicated habitat than that of the corsac fox (V. corsac). However, the adaptive mechanisms (in particular, the gut microbiome responsible for this kind of difference) are still unclear. Therefore, we investigated the gut microbiome of these two species in the Hulunbuir grassland, China, and evaluated their microbiome composition, function, and adaptive mechanisms. We profiled the gut microbiome and metabolism function of red and corsac foxes via 16S rRNA gene and metagenome sequencing. The foxes harbored species-specific microbiomes and functions that were related to ecological niche and habitat. The red fox had abundant Bacteroides, which leads to significant enrichment of metabolic pathways (K12373 and K21572) and enzymes related to chitin and carbohydrate degradation that may help the red fox adapt to a wider niche. The corsac fox harbored large proportions of Blautia, Terrisporobacter, and ATP-binding cassette (ABC) transporters (K01990, K02003, and K06147) that can help maintain corsac fox health, allowing it to live in harsh habitats. These results indicate that the gut microbiome of the red and corsac foxes may have different abilities which may provide these species with differing capabilities to adapt to different ecological niches and habitats, thus providing important microbiome data for understanding the mechanisms of host adaptation to different niches and habitats.

Overexpression of a novel gene Aokap2 affects the growth and kojic acid production in Aspergillus oryzae.

BACKGROUND: Aspergillus oryzae is an industrially important filamentous fungus for the production of fermentative food, commercial enzyme and valuable secondary metabolites. Although the whole genome of A. oryzae has been sequenced in 2005, there is currently not enough research on functional genes that affect the growth and secondary metabolites of A. oryzae. This study aimed to identify and characterize functional genes involved in the growth and secondary metabolites of A. oryzae. METHODS AND RESULTS: Our previous work on the developmental transcriptome of A. oryzae found that an uncharacterized gene Aokap2 was repressed during the development of A. oryzae. In this study, the gene expression pattern was verified by qRT-PCR. Phylogenetic analysis revealed that AoKAP2 has the species specificity of Aspergillus. Furthermore, Aokap2 was overexpressed using the A. oryzae amyB promoter and overexpression of Aokap2 caused the inhibition in mycelium growth, conidia formation and biomass. Additionally, overexpression of Aokap2 increased the production of kojic acid. In accordance with the enhanced kojic acid, the overexpression of Aokap2 led to elevated transcription levels of the key kojic acid synthesis gene kojA and the global transcriptional regulator gene of secondary metabolism laeA. Moreover, the expression of Aokap2 was down-regulated significantly in the laeA mutant. Meanwhile, overexpression of Aokap2 in the kojA disrupted strain resulted in a ΔkojA strain-like phenotype with significant inhibition in kojic acid production. CONCLUSION: Taken together, these data suggest that a novel gene Aokap2 is involved in the growth and overexpression of Aokap2 increased kojic acid production through affecting the expression of laeA and kojA. The identification of Aokap2 provides a new target for genetic modification of the growth and the production of kojic acid in A. oryzae.

Identification and characterization of a novel gene Aokap1 involved in growth and kojic acid synthesis in Aspergillus oryzae.

The elucidation of the mechanism for the growth and secondary metabolites in Aspergillus oryzae is important for industrial production and utilization. Here, we found that the expression of a novel gene Aokap1 was induced during the growth of A. oryzae. Sequence analysis revealed that AoKap1 has four transmembrane regions and is conserved in Aspergillus species. Disruption of Aokap1 caused the inhibition in mycelium growth and conidia formation, corresponding with reduced expression of brlA and abaA. Furthermore, deletion of Aokap1 resulted in elevated production of kojic acid, and the expression of kojA, kojR and kojT was up-regulated in Aokap1-disrupted strain. Meanwhile, overexpression of kojR resulted in the decreased expression of Aokap1, suggesting that disruption of Aokap1 increased kojic acid production by affecting the expression of kojA, kojR and kojT. The discovery of Aokap1 provides a new target for genetic modification of the growth and kojic acid production in A. oryzae.

Measurement of the interconnected turgor pressure and envelope elasticity of live bacterial cells.

Turgor pressure and envelope elasticity of bacterial cells are two mechanical parameters that play a dominant role in cellular deformation, division, and motility. However, a clear understanding of these two properties is lacking because of their strongly interconnected mechanisms. This study established a nanoindentation method to precisely measure the turgor pressure and envelope elasticity of live bacteria. The indentation force-depth curves of Klebsiella pneumoniae bacteria were recorded with atomic force microscopy. Through combination of dimensional analysis and numerical simulations, an explicit expression was derived to decouple the two properties of individual bacteria from the nanoindentation curves. We show that the Young's modulus of bacterial envelope is sensitive to the external osmotic environment, and the turgor pressure is significantly dependent on the external osmotic stress. This method can not only quantify the turgor pressure and envelope elasticity of bacteria, but also help resolve the mechanical behaviors of bacteria in different environments.

Impacts of Soil NOx Emission on O3 Air Quality in Rural California.

Nitrogen oxides (NOx) are a key precursor in O3 formation. Although stringent anthropogenic NOx emission controls have been implemented since the early 2000s in the United States, several rural regions of California still suffer from O3 pollution. Previous findings suggest that soils are a dominant source of NOx emissions in California; however, a statewide assessment of the impacts of soil NOx emission (SNOx) on air quality is still lacking. Here we quantified the contribution of SNOx to the NOx budget and the effects of SNOx on surface O3 in California during summer by using WRF-Chem with an updated SNOx scheme, the Berkeley Dalhousie Iowa Soil NO Parameterization (BDISNP). The model with BDISNP shows a better agreement with TROPOMI NO2 columns, giving confidence in the SNOx estimates. We estimate that 40.1% of the state's total NOx emissions in July 2018 are from soils, and SNOx could exceed anthropogenic sources over croplands, which accounts for 50.7% of NOx emissions. Such considerable amounts of SNOx enhance the monthly mean NO2 columns by 34.7% (53.3%) and surface NO2 concentrations by 176.5% (114.0%), leading to an additional 23.0% (23.2%) of surface O3 concentration in California (cropland). Our results highlight the cobenefits of limiting SNOx to help improve air quality and human health in rural California.

Transcriptome aberration associated with altered locomotor behavior of zebrafish (Danio rerio) caused by Waterborne Benzo[a]pyrene.

Waterborne Benzo[a]pyrene (B[a]P) pollution is a global threat to aquatic organisms. The exposure to waterborne B[a]P can disrupt the normal locomotor behavior of zebrafish (Danio rerio), however, how it affect the locomotor behavior of adult zebrafish remains unclear. Herein, B[a]P at two concentrations (0.8 µg/L and 2.0 µg/L) were selected to investigate the molecular mechanisms of the affected locomotor behavior of zebrafish by B[a]P based on transcriptome profiling. Adverse effects of B[a]P exposure affecting locomotor behavior in zebrafish were studied by RNA sequencing, and the locomotion phenotype was acquired. The gene enrichment results showed that the differentially highly expressed genes (atp2a1, cdh2, aurka, fxyd1, clstn1, apoc1, mt-co1, tnnt3b, and fads2) of zebrafish are mainly enriched in adrenergic signaling in cardiomyocytes (dre04261) and locomotory behavior (GO:0007626). The movement trajectory plots showed an increase in the locomotor distance and velocity of zebrafish in the 0.8 µg/L group and the opposite in the 2.0 µg/L group. The results showed that B[a]P affects the variety of genes in zebrafish, including motor nerves, muscles, and energy supply, and ultimately leads to altered locomotor behavior.

A highly efficient identification of mutants generated by CRISPR/Cas9 using the non­functional DsRed assisted selection in Aspergillus oryzae.

The CRISPR/Cas9 system has become a great tool for target gene knock-out in filamentous fungi. It is laborious and time-consuming that identification mutants from a large number of transformants through PCR or enzyme-cut method. Here, we first developed a CRISPR/Cas9 system in Aspergillus oryzae using AMA1-based autonomously replicating plasmid and Cas9 under the control of the Aspergillus nidulans gpdA promoter. By the genome editing technique, we successfully obtained mutations within each target gene in Aspergillus oryzae. Then, we put the protospacer sequence of a target gene and its protospacer adjacent motif (PAM) behind the start codon "ATG" of DsRed, yielding the non­functional DsRed (nDsRed) reporter gene, and the nDsRed reporter gene could be rescued after successful targeted editing. Moreover, this method was also applied by targeting the kojic acid synthesis gene kojA, and the transformants with DsRed activity were found to harbor targeted mutations in kojA. These results suggest that the nDsRed can be used as a powerful tool to facilitate the identification of mutants generated by CRISPR/Cas9 in Aspergillus oryzae.

High expression of miR-363 predicts poor prognosis and guides treatment selection in acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) is a highly heterogeneous malignancy with various outcomes, and therefore needs better risk stratification tools to help select optimal therapeutic options. METHODS: In this study, we identify miRNAs that could predict clinical outcome in a heterogeneous AML population using TCGA dataset. RESULTS: We found that MiR-363 is a novel prognostic factor in AML patients undergoing chemotherapy. In multivariable analyses, high miR-363 remained predictive for shorter OS (HR = 2.349, P = 0.012) and EFS (HR = 2.082, P = 0.001) independent of other well-known prognostic factors. More importantly, allogeneic hematopoietic stem cell transplantation (allo-HSCT) overcame the adverse outcomes related to high miR-363 expression. In gene expression profiling, high miR-363 expression was positively correlated with the amounts of leukemogenic transcription factors, including Myb, RUNX3, GATA3, IKZF3, ETS1 and MLLT3. Notably, we found that the in silico predicted target genes (EZH2, KLF6 and PTEN) of miR-363 were downregulated in association with high miR-363 expression. CONCLUSIONS: In summary, miR-363 expression may help identify patients in need of strategies to select the optimal therapy between chemotherapeutic and allo-HCST regimens. AML patients with high miR-363 expression may be highly recommended for early allo-HSCT regimen.

Characterization and phylogeny of bitter taste receptor genes (Tas2r) in Squamata.

The perception of bitter taste is linked to the detection of toxins. Therefore, it facilitates avoiding the consumption of potential toxins in the diet. At the molecular level, bitter taste is mediated by taste 2 receptors (Tas2rs). Studies on Tas2r have made major advances in recent years. However, little is known about Tas2rs in Squamata, the second largest order of extant vertebrates. To explore the repertoire and phylogenetic relationships among Tas2r genes in Squamata, we identified and characterized Tas2rs from genome assemblies of 15 Squamata species. We observed considerable Tas2r contraction and expansion in the suborders Serpentes and Lacertilia, respectively. Phylogenetic and reconciliation analysis suggested that lineage-specific gene gains and losses could have led to the Tas2r contraction and expansion in Squamata. Different Tas2r repertoires in Serpents and Lacertilia also reflect their oral anatomical features and taste behaviors. Our findings offer novel perspectives into the study of taste and dietary protection in Squamata species.

One-Pot Asymmetric Synthesis of Spiropyrazolone-Linked Cyclopropanes and Benzofurans through a General Michael Addition/Chlorination/Nucleophilic Substitution Sequence.

A sequential and general strategy has been successfully developed for the synthesis of spiropyrazolone scaffolds. This intriguing transformation of the asymmetric multicomponent catalysis process was realized with the combination of Michael addition/chlorination/nucleophilic substitution in a one-pot sequence, giving rise to a series of spiropyrazolones with fully substituted cyclopropanes and spiro-dihydrobenzofurans containing continuous stereogenic centers in good yields with excellent stereoselectivities.

Participation of ß-Ketothioamides in N-Heterocyclic Carbene-Catalyzed [3 + 3] Spiroannulation: Asymmetric Synthesis of Functionalized Spiro-piperidinone Derivatives.

An N-heterocyclic carbene-catalyzed asymmetric [3 + 3] spiroannulation of ß-ketothioamide was successfully developed. ß-Ketothioamides exhibit an unusual reactivity to undergo a previously challenging lactamization reaction, and the desired spiro-piperidinone derivatives containing two vicinal stereogenic centers were synthesized in good to high yields with high stereoselectivities, whose structure can be converted to the corresponding imide and δ-lactam derivatives smoothly.