Uncovering the role of ferroptosis in Bietti crystalline dystrophy and potential therapeutic strategies.

PURPOSE: Bietti crystalline dystrophy (BCD) is an inherited retinal degeneration disease caused by mutations in the CYP4V2 gene. Currently, there is no clinical therapy approach available for BCD patients. Previous research has suggested that polyunsaturated fatty acids (PUFAs) may play a significant role in the development of BCD, implicating the involvement of ferroptosis in disease pathogenesis. In this work, we aimed to investigate the interplay between ferroptosis and BCD and to detect potential therapeutic strategies for the disease. METHODS: Genetic-edited RPE cell line was first established in this study by CRISPR-Cas9 technology. Cyp4v3 (the homologous gene of human CYP4V2) knock out (KO) mice have also been used. Lipid profiling and transcriptome analysis of retinal pigment epithelium (RPE) cells from Cyp4v3 KO mice have been conducted. Ferroptosis phenotypes have been first investigated in BCD models in vitro and in vivo, including lipid peroxidation, mitochondrial changes, elevated levels of reactive oxygen species (ROS), and altered gene expression. Additionally, an iron chelator, deferiprone (DFP), has been tested in vitro and in vivo to determine its efficacy in suppressing ferroptosis and restoring the BCD phenotype. RESULTS: Cyp4v3 KO mice exhibited progressive retinal degeneration and lipid accumulation, similar to the BCD phenotype, which was exacerbated by a high-fat diet (HFD). Increased levels of PUFAs, such as EPA (C22:5) and AA (C20:4), were observed in the RPE of Cyp4v3 KO mice. Transcriptome analysis of RPE in Cyp4v3 KO mice revealed changes in genes involved in iron homeostasis, particularly an upregulation of NCOA4, which was confirmed by immunofluorescence. Ferroptosis-related characteristics, including mitochondrial defects, lipid peroxidation, ROS accumulation, and upregulation of related genes, were detected in the RPE both in vitro and in vivo. Abnormal accumulation of ferrous iron was also detected. DFP, an iron chelator administration suppressed ferroptosis phenotype in CYP4V2 mutated RPE. Oral administration of DFP also restored the retinal function and morphology in Cyp4v3 KO mice. CONCLUSION: This study represented the first evidence of the substantial role of ferroptosis in the development of BCD. PUFAs resulting from CYP4V2 mutation may serve as substrates for ferroptosis, potentially working in conjunction with NCOA4-regulated iron accumulation, ultimately leading to RPE degeneration. DFP administration, which chelates iron, has demonstrated its ability to reverse BCD phenotype both in vitro and in vivo, suggesting a promising therapeutic approach in the future.

Seed yield as a function of cytokinin-regulated gene expression in wild Kentucky bluegrass (Poa pratensis).

BACKGROUND: Kentucky bluegrass (Poa pratensis L.) panicle development is a coordinated process of cell proliferation and differentiation with distinctive phases and architectural changes that are pivotal to determine seed yield. Cytokinin (CK) is a key factor in determining seed yield that might underpin the second "Green Revolution". However, whether there is a difference between endogenous CK content and seed yields of Kentucky bluegrass, and how CK-related genes are expressed to affect enzyme regulation and downstream seed yield in Kentucky bluegrass remains enigmatic. RESULTS: In order to establish a potential link between CK regulation and seed yield, we dissected and characterized the Kentucky bluegrass young panicle, and determined the changes in nutrients, 6 types of endogenous CKs, and 16 genes involved in biosynthesis, activation, inactivation, re-activation and degradation of CKs during young panicle differentiation of Kentucky bluegrass. We found that high seed yield material had more meristems compared to low seed yield material. Additionally, it was found that seed-setting rate (SSR) and lipase activity at the stage of spikelet and floret primordium differentiation (S3), as well as 1000-grain weight (TGW) and zeatin-riboside (ZR) content at the stages of first bract primordium differentiation (S1) and branch primordium differentiation (S2) showed a significantly positive correlation in the two materials. And zeatin, ZR, dihydrozeatin riboside, isopentenyl adenosine and isopentenyl adenosine riboside contents were higher in seed high yield material than those in seed low yield material at S3 stage. Furthermore, the expressions of PpITP3, PpITP5, PpITP8 and PpLOG1 were positively correlated with seed yield, while the expressions of PpCKX2, PpCKX5 and PpCKX7 were negatively correlated with seed yield in Kentucky bluegrass. CONCLUSIONS: Overall, our study established a relationship between CK and seed yield in Kentucky bluegrass. Perhaps we can increase SSR and TGW by increasing lipase activity and ZR content. Of course, using modern gene editing techniques to manipulate CK related genes such as PpITP3/5/8, PpLOG1 and PpCKX2/5/7, will be a more direct and effective method in Kentucky bluegrass, which requires further trial validation.

Integrated proteomics, transcriptomics, and metabolomics offer novel insights into Cd resistance and accumulation in Poa pratensis.

Kentucky bluegrass (Poa pratensis L., KB) demonstrates superior performance in both cadmium (Cd) accumulation and tolerance; however, the regulatory mechanisms and detoxification pathways in this species remain unclear. Therefore, phenotype, root ultrastructure, cell wall components, proteomics, transcriptomics, and metabolomics were analyzed under the hydroponic system to investigate the Cd tolerance and accumulation mechanisms in the Cd-tolerant KB variety 'Midnight (M)' and the Cd-sensitive variety 'Rugby II (R)' under Cd stress. The M variety exhibited higher levels of hydroxyl and carboxyl groups as revealed by Fourier transform infrared spectroscopy spectral analysis. Additionally, a reduced abundance of polysaccharide degradation proteins was observed in the M variety. The higher abundance of glutathione S-transferase and content of L-cysteine-glutathione disulfide and oxidized glutathione in the M variety may contribute to better performance of the M variety under Cd stress. Additionally, the R variety had an enhanced content of carboxylic acids and derivatives, increasing the Cd translocation capacity. Collectively, the down-regulation of cell wall polysaccharide degradation genes coupled with the up-regulation of glutathione metabolism genes enhances the tolerance to Cd stress in KB. Additionally, lignification of the endodermis and the increase in carboxylic acids and derivatives play crucial roles in the redistribution of Cd in KB.

Characterization and Comparative Analysis of Complete Chloroplast Genomes of Four Bromus (Poaceae, Bromeae) Species.

Bromus (Poaceae Bromeae) is a forage grass with high adaptability and ecological and economic value. Here, we sequenced Bromus ciliatus, Bromus benekenii, Bromus riparius, and Bromus rubens chloroplast genomes and compared them with four previously described species. The genome sizes of Bromus species ranged from 136,934 bp (Bromus vulgaris) to 137,189 bp (Bromus ciliates, Bromus biebersteinii), with a typical quadripartite structure. The studied species had 129 genes, consisting of 83 protein-coding, 38 tRNA-coding, and 8 rRNA-coding genes. The highest GC content was found in the inverted repeat (IR) region (43.85-44.15%), followed by the large single-copy (LSC) region (36.25-36.65%) and the small single-copy (SSC) region (32.21-32.46%). There were 33 high-frequency codons, with those ending in A/U accounting for 90.91%. A total of 350 simple sequence repeats (SSRs) were identified, with single-nucleotide repeats being the most common (61.43%). A total of 228 forward and 141 palindromic repeats were identified. No reverse or complementary repeats were detected. The sequence identities of all sequences were very similar, especially with respect to the protein-coding and inverted repeat regions. Seven highly variable regions were detected, which could be used for molecular marker development. The constructed phylogenetic tree indicates that Bromus is a monophyletic taxon closely related to Triticum. This comparative analysis of the chloroplast genome of Bromus provides a scientific basis for species identification and phylogenetic studies.

Root cell wall polysaccharides and endodermal barriers restrict long-distance Cd translocation in the roots of Kentucky bluegrass.

Soil Cd pollution is a significant environmental issue faced by contemporary society. Kentucky bluegrass is considered a potential phytoremediation species, as some varieties have excellent cadmium (Cd) tolerance. However, the mechanisms of Cd accumulation and transportation in Kentucky bluegrass are still not fully understood. The Cd-tolerant Kentucky bluegrass cultivar 'Midnight' (M) exhibits lower Cd translocation efficiency and a higher leaf Cd concentration compared to the Cd-sensitive cultivar 'Rugby II' (R). We hypothesized that Cd translocation from roots to shoots in cultivar M is hindered by the endodermal barriers and cell wall polysaccharides; hence, we conducted Cd distribution, cytological observation, cell wall component, and transcriptomic analyses under Cd stress conditions using the M and R cultivars. Cd stress resulted in the thickening of the endodermis and increased synthesis of cell wall polysaccharides in both the M and R cultivars. Endodermis development restricted the radical transport of Cd from the root cortex to the stele, while the accumulation of cell wall polysaccharides promoted the binding of Cd to the cell wall. These changes further inhibited the long-distance translocation of Cd from the roots to the aerial parts. Furthermore, the M cultivar exhibited limited long-distance Cd translocation efficiency compared to the R cultivar, which was attributed to the enhanced development of endodermal barriers and increased Cd binding by cell wall polysaccharides. This study provides valuable insights for screening high Cd transport efficiency in Kentucky bluegrass based on anatomical structure and genetic modification.

TaWRKY31, a novel WRKY transcription factor in wheat, participates in regulation of plant drought stress tolerance.

BACKGROUND: Wheat, a crucial food crop in China, is highly vulnerable to drought stress throughout its growth and development. WRKY transcription factors (TFs), being one of the largest families of TFs, play a vital role in responding to various abiotic stresses in plants. RESULTS: Here, we cloned and characterized the TF TaWRKY31 isolated from wheat. This TF, belonging to the WRKY II family, contains a WRKYGQK amino acid sequence and a C2H2-type zinc finger structure. TaWRKY31 exhibits tissue-specific expression and demonstrates responsiveness to abiotic stresses in wheat. TaWRKY31 protein is localized in the nucleus and can function as a TF with transcription activating activity at the N-terminus. Results showed that the wheat plants with silenced strains (BSMV:TaWRKY31-1as and BSMV:TaWRKY31-2as) exhibited poor growth status and low relative water content when subjected to drought treatment. Moreover, the levels of O2·-, H2O2, and malondialdehyde (MDA) in the BSMV:TaWRKY31-induced wheat plants increased, while the activities of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase) decreased. Compared to control plants, BSMV:TaWRKY31-induced wheat plants exhibited lower expression levels of TaSOD (Fe), TaPOD, TaCAT, TaDREB1, TaP5CS, TaNCED1, TaSnRK2, TaPP2C, and TaPYL5.Under stress or drought treatment conditions, the overexpression of TaWRKY31 in Arabidopsis resulted in decreased levels of H2O2 and MDA, as well as reduced stomatal opening and water loss. Furthermore, an increase in resistance oxidase activity, germination rate, and root length in the TaWRKY31 transgenic Arabidopsis was observed. Lastly, overexpression of TaWRKY31 in Arabidopsis resulted in higher the expression levels of AtNCED3, AtABA2, AtSnRK2.2, AtABI1, AtABF3, AtP5CS1, AtSOD (Cu/Zn), AtPOD, AtCAT, AtRD29A, AtRD29B, and AtDREB2A than in control plants. CONCLUSIONS: Our findings indicate that TaWRKY31 enhances drought resistance in plants by promoting the scavenging of reactive oxygen species, reducing stomatal opening, and increasing the expression levels of stress-related genes.

Ni-Catalyzed Hydrosulfonylation of Alkenes with Aromatic Iodides and K2S2O5.

Hydrosulfonylation of alkenes with readily available aromatic iodides via a SO2-insetion strategy is presented. The combination of non-noble Ni catalysis with (iPr)3SiH as the final reductant enables the efficient formation of aryl and heteroaryl sulfinate intermediates, which undergo Michael-type additions to electron-deficient alkenes for initiating the hydrosulfonylation process. Moreover, the superiority of this protocol is demonstrated by broad substrate scope and good functional group compatibility.

Genome-wide identification and expression analysis of the Auxin-Response factor (ARF) gene family in Medicago sativa under abiotic stress.

BACKGROUND: Alfalfa (Medicago sativa) is the most widely planted legume forage and one of the most economically valuable crops in the world. The periodic changes in its growth and development and abiotic stress determine its yield and economic benefits. Auxin controls many aspects of alfalfa growth by regulating gene expression, including organ differentiation and stress response. Auxin response factors (ARF) are transcription factors that play an essential role in auxin signal transduction and regulate the expression of auxin-responsive genes. However, the function of ARF transcription factors is unclear in autotetraploid-cultivated alfalfa. RESULT: A total of 81 ARF were identified in the alfalfa genome in this study. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were analyzed, identifying that ARF genes are mainly involved in transcriptional regulation and plant hormone signal transduction pathways. Phylogenetic analysis showed that MsARF was divided into four clades: I, II, III, and IV, each containing 52, 13, 7, and 9 genes, respectively. The promoter region of the MsARF gene contained stress-related elements, such as ABRE, TC-rich repeats, MBS, LTR. Proteins encoded by 50 ARF genes were localized in the nucleus without guide peptides, signal peptides, or transmembrane structures, indicating that most MsARF genes are not secreted or transported but only function in the nucleus. Protein structure analysis revealed that the secondary and tertiary structures of the 81 MsARF genes varied. Chromosomal localization analysis showed 81 MsARF genes were unevenly distributed on 25 chromosomes, with the highest distribution on chromosome 5. Furthermore, 14 segmental duplications and two sets of tandem repeats were identified. Expression analysis indicated that the MsARF was differentially expressed in different tissues and under various abiotic stressors. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis showed that the expression profiles of 23 MsARF genes were specific to abiotic stresses such as drought, salt, high temperature, and low temperature, as well as tissue-specific and closely related to the duration of stress. CONCLUSION: This study identified MsARF in the cultivated alfalfa genome based on the autotetraploid level, which GO, KEGG analysis, phylogenetic analysis, sequence characteristics, and expression pattern analysis further confirmed. Together, these findings provide clues for further investigation of MsARF functional verification and molecular breeding of alfalfa. This study provides a novel approach to systematically identify and characterize ARF transcription factors in autotetraploid cultivated alfalfa, revealing 23 MsARF genes significantly involved in response to various stresses.

Walnut green husk extract enhances the effect of chlorine dioxide on kernel quality and antioxidant properties of fresh-eating walnuts during their shelf life.

Fresh-eating walnuts are perishable and become mildewed during shelf life, limiting their sales span. The effects of chlorine dioxide (ClO2) alone and its combination with walnut green husk extract (WGHE) on shelf stored fresh walnuts were investigated to develop a pollution-free preservative for the produce. The initial development of mildew incidence was delayed by both treatments under 25 °C, whereas, WGHE + ClO2 acted more effectively than ClO2 under 5 °C. The WGHE + ClO2 treatment presented superior effects on improving moisture, soluble sugar and total phenol content, alleviating loss of oil and unsaturated fatty acid and delaying peroxide value increase of walnut kernels at both temperatures. Both treatments inhibited the activities of three lipolytic enzymes and two oxidases at 25 °C and 5 °C, WGHE + ClO2 acted more effectively at 5 °C. The results guide the combined application of WGHE with ClO2 on shelf preservation of fresh walnut.

Radiation synthesis of MXene/Ag nanoparticle hybrids for efficient photothermal conversion of polyurethane films.

Flexible conductive films based on light-to-heat conversion are promising for the next-generation electronic devices. A flexible waterborne polyurethane composite film (PU/MA) with excellent photothermal conversion performance was obtained by combination of PU and silver nanoparticle decorated MXene (MX/Ag). The silver nanoparticles (AgNPs) uniformly decorated on the MXene surface by γ-ray irradiation induced reduction. Because of the synergistic effect of MXene with outstanding light-to-heat conversion efficiency and the AgNPs with plasmonic effect, the surface temperature of the PU/MA-II (0.4%) composite with lower MXene content increased from room temperature to 60.7 °C at 5 min under 85 mW cm-2 light irradiation. Besides, the tensile strength of PU/MA-II (0.4%) increased from 20.9 MPa (pure PU) to 27.5 MPa. The flexible PU/MA composite film shows great potential in the field of thermal management of flexible wearable electronic devices.

Bicarbonate transporter SLC4A7 promotes EMT and metastasis of HNSCC by activating the PI3K/AKT/mTOR signaling pathway.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Currently, therapeutic modalities such as surgery, chemotherapy, radiotherapy, and immunotherapy are being used to treat HNSCC. However, the treatment outcomes of most patients are dismal because they are already in middle or advanced stage by the time of diagnosis and poorly responsive to treatments. It is therefore of great interest to clarify mechanisms that contribute to the metastasis of cells to identify possible targets for therapy. In this study, we identified the Na+ -coupled bicarbonate transporter, SLC4A7, play essential roles in the metastasis of HNSCC. Our results showed that the relative expression of SLC4A7 messenger RNA was highly expressed in HNSCCs samples from TCGA, and compared with precancerous cells of human oral mucosa (DOK), SLC4A7 was highly expressed in HNSCC cell lines. In vitro and in vivo experiments showed that dysregulation of SLC4A7 had minor influence on the proliferation of HNSCC but impacted HNSCC's migration and invasion. Meanwhile, SLC4A7 could promote epithelial-mesenchymal transition (EMT) in HNSCC. RNA-seq, KEGG pathway enrichment analysis and Western blot further revealed that downregulation of SLC4A7 in HNSCC cells inhibited the PI3K/AKT pathway. These findings were further validated via rescue experiments using a small molecule inhibitor of PI3K/mTOR (GDC-0980). Our findings suggest that SLC4A7 promotes EMT and metastasis of HNSCC through the PI3K/AKT/mTOR signaling pathway, which may be a valuable predictive biomarker and potential therapeutic target in HNSCC.

Stereolithography apparatus and digital light processing-based 3D bioprinting for tissue fabrication.

Three-dimensional (3D) bioprinting has emerged as a class of promising techniques in biomedical research for a wide range of related applications. Specifically, stereolithography apparatus (SLA) and digital light processing (DLP)-based vat-polymerization techniques are highly effective methods of bioprinting, which can be used to produce high-resolution and architecturally sophisticated structures. Our review aims to provide an overview of SLA- and DLP-based 3D bioprinting strategies, starting from factors that affect these bioprinting processes. In addition, we summarize the advances in bioinks used in SLA and DLP, including naturally derived and synthetic bioinks. Finally, the biomedical applications of both SLA- and DLP-based bioprinting are discussed, primarily centered on regenerative medicine and tissue modeling engineering.

Auxin alleviates cadmium toxicity by increasing vacuolar compartmentalization and decreasing long-distance translocation of cadmium in Poa pratensis.

Kentucky bluegrass (Poa pratensis L.) hyperaccumulates cadmium (Cd) and exhibits a hypertolerance. Thus, it has potential for the phytoremediation of Cd-containing soil. Auxin signaling is involved in the response to Cd stress. However, the mechanisms of auxin-mediated detoxification and Cd translocation in plants remain unclear. This study aimed to investigate the effects of exogenous application of indole-3-acetic acid (IAA) on the Cd translocation, subcellular Cd distribution, chemical forms of Cd, and transcriptional regulation of Kentucky bluegrass. The results showed that the exogenous application of IAA increased the amount of organelle-bound Cd and vacuole-compartmentalized Cd in root cells, reduced the Cd concentration in the leaf tissues (epidermis, mesophyll, and vascular bundle) and root tissues (rhizodermis and cortex) but increased in the stele, and alleviate Cd-induced leaf chlorosis and growth inhibition. The expression of genes associated with Cd transporters (ABCs, ZIPs, NASs, OPTs, and YSLs), phosphatases, oxalate decarboxylases and lignin biosynthesis were significantly regulated by exogenous IAA under Cd stress. A positive regulation of phosphatases and oxalate decarboxylases genes related to an increase in phosphate- and oxalate-bound Cd, as well as a decrease in pectate- and protein-bound Cd and inorganic Cd, thereby contributing to a decrease in Cd phytotoxicity. The significant regulation of Cd transporters associated with decreasing the long-distance translocation of Cd, and the activation of lignin biosynthesis may contribute to the development of root endodermal barriers and increase the deposition of undissolved Cd phosphates and oxalate-bound Cd in the stele. These results revealed the important role of auxin in Cd detoxification and translocation in Kentucky bluegrass and they provide a theoretical basis for the phytoremediation of Cd-containing soil.

Antimicrobial peptide AMP-17 exerts anti–Candida albicans effects through ROS-mediated apoptosis and necrosis / Péptido antimicrobiano AMP-17 ejerce efectos albicans anti-Candida a través de ROS-mediada apoptosis y necrosis

There is a need for new anti–Candida albicans (C. albicans) drugs owing to the emergence of drug resistance in recent years. AMP-17, an antimicrobial peptide from Musca domestica (M. domestica), is known to be an effective inhibitor of many fungal pathogens, including C. albicans. In this study, we investigated the potential mechanism underlying the anti–C. albicans effects of AMP-17 using flow cytometry, transmission electron microscopy, fluorescent probes, fluorescence microplate reader, and confocal laser microscopy. Transmission electron microscopy showed that, following AMP-17 treatment, the shape of C. albicans cells became irregular, and vacuoles could be seen in the cytoplasm. Furthermore, AMP-17 treatment resulted in an increase in reactive oxygen species (ROS) levels, depolarization of the mitochondrial membrane potential (MMP), and changes in the cell cycle, leading to the apoptosis and necrosis, which ultimately contributed to the death of C. albicans cells.(AU)

Antimicrobial peptide AMP-17 exerts anti-Candida albicans effects through ROS-mediated apoptosis and necrosis.

There is a need for new anti-Candida albicans (C. albicans) drugs owing to the emergence of drug resistance in recent years. AMP-17, an antimicrobial peptide from Musca domestica (M. domestica), is known to be an effective inhibitor of many fungal pathogens, including C. albicans. In this study, we investigated the potential mechanism underlying the anti-C. albicans effects of AMP-17 using flow cytometry, transmission electron microscopy, fluorescent probes, fluorescence microplate reader, and confocal laser microscopy. Transmission electron microscopy showed that, following AMP-17 treatment, the shape of C. albicans cells became irregular, and vacuoles could be seen in the cytoplasm. Furthermore, AMP-17 treatment resulted in an increase in reactive oxygen species (ROS) levels, depolarization of the mitochondrial membrane potential (MMP), and changes in the cell cycle, leading to the apoptosis and necrosis, which ultimately contributed to the death of C. albicans cells.

24-epibrassinolide improves cadmium tolerance and lateral root growth associated with regulating endogenous auxin and ethylene in Kentucky bluegrass.

The application of phytohormones is a viable technique to increase the efficiency of phytoremediation in heavy metal-contaminated soils. The objective of this study was to determine how the application of 24-epibrassinolide (EBR), a brassinosteroid analog, could regulate root growth and tolerance to cadmium (Cd) stress in Kentucky bluegrass. As a result, the number of lateral root primordia and total root length in the Cd-treated seedlings decreased by 33.1 % and 56.5 %, respectively. After the application of EBR, Cd accumulation in roots and leaves, and the negative effect of Cd on root growth were reduced under Cd stress. Additionally, the expression of the brassinosteroid signaling gene PpBRI1 was significantly upregulated by exogenous EBR. Moreover, exogenous EBR upregulated the expression of genes encoding antioxidant enzymes and improved the activity of antioxidant enzymes, thereby reduced oxidative stress in roots. Finally, targeted hormonomics analysis highlighted the utility of the application of EBR to alleviate the effect of Cd on the reduction in auxin (IAA) content and the increase in ethylene (ACC) content. These were known to be associated with the upregulation in the expression of auxin biosynthesis gene PpYUCCA1 and downregulation in the expression of ethylene biosynthesis gene PpACO1 in the roots treated with Cd stress. Overall, the application of EBR alleviated Cd-induced oxidative stress in addition to improving root elongation and lateral root growth crosstalk with auxin and ethylene in Kentucky bluegrass subjected to Cd stress. This study further highlights the potential role of brassinosteroids in improving the efficiency of phytoremediation for Cd-contaminated soils.

MXene/Gelatin/Polyacrylamide Nanocomposite Double Network Hydrogel with Improved Mechanical and Photothermal Properties.

The development of smart hydrogel with excellent mechanical properties and photothermal conversion capability is helpful in expending its application fields. Herein, a MXene/gelatin/polyacrylamide (M/G/PAM) nanocomposite double network (NDN) hydrogel was synthesized by γ-ray radiation technology for the first time. Compared with gelatin/polyacrylamide double network hydrogel, the optimized resultant M3/G/PAM NDN hydrogel shows better mechanical properties (tensile strength of 634 ± 10 kPa, compressive strength of 3.44 ± 0.12 MPa at a compression ratio of 90%). The M3/G/PAM NDN hydrogel exhibits a faster heating rate of 30 °C min-1, stable photothermal ability, and mechanical properties even after 20 cycles of on-off 808 nm near-infrared (NIR) laser irradiation (1.0 W cm-2). Furthermore, the temperature of M3/G/PAM NDN hydrogel can be increased rapidly from 25 °C to 90 °C in 10 s and could reach 145 °C in 120 s under irradiation by focused NIR laser irradiation (56.6 W cm-2). The high mechanical property and photothermal properties of M/G/PAM hydrogel are ascribed to the formation of double network and uniform hydrogen bonding between MXene and gelatin and PAM polymers. This work paves the way for construction of photothermal hydrogels with excellent mechanical properties.

Comparative transcriptome analysis of resistant and susceptible Kentucky bluegrass varieties in response to powdery mildew infection.

BACKGROUND: Poa pratensis is one of the most common cold-season turfgrasses used for urban turf building, and it is also widely used in ecological environment management worldwide. Powdery mildew is a common disease of P. pratensis. To scientifically and ecologically control lawn powdery mildew, the molecular mechanism underlying the response of P. pratensis to powdery mildew infection must better understood. RESULTS: To explore molecular mechanism underlying the response of P. pratensis to powdery mildew infection, this study compared physiological changes and transcriptomic level differences between the highly resistant variety 'BlackJack' and the extremely susceptible variety 'EverGlade' under powdery mildew infection conditions. We analyzed DEGs using reference canonical pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the results showed that "starch and sucrose metabolism", "photosynthesis" and "fatty acid metabolism"pathways were only enriched in 'BlackJack', and the expression of DEGs such as HXK, INV, GS, SS, AGpase and ß-amylase in "starch and sucrose metabolism" pathway of 'BlackJack' were closely related to powdery mildew resistance. Meanwhile, compared with 'EverGlade', powdery mildew infection promoted synthesis of sucrose, expression of photosynthesis parameters and photosynthesis-related enzymes in leaves of 'BlackJack' and decreased accumulation of monosaccharides such as glucose and fructose. CONCLUSIONS: This study identified the key metabolic pathways of a P. pratensis variety with high resistance to powdery mildew infection and explored the differences in physiological characteristics and key genes related to sugar metabolism pathways under powdery mildew stress. These findings provide important insights for studying underlying molecular response mechanism.

Identification and expression analysis of the MADS-box genes of Kentucky bluegrass during inflorescence development.

MADS-box genes play vital roles in multiple biological processes of plants growth and development, especially inflorescence development. In the present study, a comprehensive investigation into the identification and classification of MADS-box genes in Kentucky bluegrass (Poa pratensis) has not been reported. Here, based on the transcriptome of inflorescence, we identified 44 PpMADS-box genes, and gave an overview of the physicochemical properties, phylogeny, protein structures, and potential functions of the proteins encoded by these genes through various bioinformatics software for the first time. Analysis of physicochemical properties revealed that most PpMADS-box were alkaline proteins and possessed similar conserved motifs. Additionally, it was demonstrated that 33 PpMADS-box proteins without signal peptide, leading peptide, transmembrane structure and located in the nucleus were not transported or secreted, so directly played transcriptional regulatory roles in the nucleus. Then, peptide sequences BLAST search and analysis of phylogenetic relationships with MADS-box proteins of P. pratensis, Arabidopsis thaliana, and Oryza sativa were performed. It was found that 44 PpMADS-box proteins were separated into 33 MIKC-type (3 BS, 1 AGL17, 8 AP3/P2, 3 AP1, 5 SEP, 6 SOC and 7 AG genes, respectvely) and 11 type I-type, which include 7 Mγ and 4 Mα. Furthermore, the relative expression levels of the selected 12 genes (MADS3, 15, 16, 17, 18, 20, 24, 27, 30, 36, 38 and 40) at the booting stage, pre-anthesis, anthesis, post-anthesis, and seed filling stage of inflorescences, as well as leaves and roots of the corresponding stages of inflorescences were analyzed, showing that most PpMADS-box genes were highly expressed mainly in young leaves and later inflorescences, and had complex patters in roots. Morever, except for PpMADS30 being highly expressed in the leaves, others were significantly highly expressed in inflorescence and/ or roots, demonstrating PpMADS-box genes also regulate leaves and roots development in plant. This study provides valuable insights into the MADS-box family genes in Kentucky bluegrass and its potential functional characteristics, expression pattern, and evolution in floral organogenesis and even reproduction development. @media print { .ms-editor-squiggler { display:none !important; } } .ms-editor-squiggler { all: initial; display: block !important; height: 0px !important; width: 0px !important; }. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01216-1.

Ultrastretchable and adhesive agarose/Ti3C2Tx-crosslinked-polyacrylamide double-network hydrogel for strain sensor.

A novel agarose/Ti3C2Tx-crosslinked-polyacrylamide (AG/T-PAM) double-network (DN) hydrogel is synthesized by combining heating-cooling and γ-ray radiation-induced polymerization. The AG/T-PAM DN hydrogel possesses excellent mechanical properties with 4250% stretchability, and good adhesion to different substrates, such as an adhesive strength of 1148 kPa to copper at 30 °C. The resultant hydrogel also exhibits excellent tensile and compression sensing properties due to the variation of conductive network within hydrogel. The flexible and wearable strain sensor composed of the AG/T-PAM DN hydrogel presents rapid response to strain withstand 1000 cycles, and can monitor various movements of human body with a high sensibility. The AG/T-PAM DN hydrogel-based strain sensor will have broad application in large-scale strain detection scenarios requiring high sensitivity and adhesion.