Sucrose promotes cone enlargement via the TgNGA1-TgWRKY47-TgEXPA2 module in Torreya grandis.

Cone enlargement is a crucial process for seed production and reproduction in gymnosperms. Most of our knowledge of cone development is derived from observing anatomical structure during gametophyte development. Therefore, the exact molecular mechanism underlying cone enlargement after fertilization is poorly understood. Here, we demonstrate that sucrose promotes cone enlargement in Torreya grandis, a gymnosperm species with relatively low rates of cone enlargement, via the TgNGA1-TgWRKY47-TgEXPA2 pathway. Cell expansion plays a significant role in cone enlargement in T. grandis. 13C labeling and sucrose feeding experiments indicated that sucrose-induced changes in cell size and number contribute to cone enlargement in this species. RNA-sequencing analysis, transient overexpression in T. grandis cones, and stable overexpression in tomato (Solanum lycopersicum) suggested that the expansin gene TgEXPA2 positively regulates cell expansion in T. grandis cones. The WRKY transcription factor TgWRKY47 directly enhances TgEXPA2 expression by binding to its promoter. Additionally, the NGATHA transcription factor TgNGA1 directly interacts with TgWRKY47. This interaction suppresses the DNA-binding ability of TgWRKY47, thereby reducing its transcriptional activation on TgEXPA2 without affecting the transactivation ability of TgWRKY47. Our findings establish a link between sucrose and cone enlargement in T. grandis and elucidate the potential underlying molecular mechanism.

IRR1 contributes to de novo root regeneration from Arabidopsis thaliana leaf explants.

Plants are capable of regenerating adventitious roots (ARs), which is important for plant response to stress and survival. Although great advances in understanding AR formation of leaf explants have been made, the regulatory mechanisms of AR formation still need to be investigated. In this study, irr1-1 (impaired root regeneration) was isolated with the inhibition of adventitious rooting from Arabidopsis leaf explants. The ß-glucuronidase (GUS) signals of IRR1pro::GUS in detached leaves could be detected at 2-6 days after culture. IRR1 is annotated to encode a Class III peroxidase localized in the cell wall. The total peroxidase (POD) activity of irr1 mutants was significantly lower than that of the wild type. Detached leaves of irr1 mutants showed enhanced reactive oxygen species (ROS) accumulation 4 days after leaves were excised from seedlings. Moreover, thiourea, a ROS scavenger, was able to rescue the adventitious rooting rate in leaf explants of irr1 mutants. Addition of 0.1 µM indole-3-acetic acid (IAA) improved the adventitious rooting from leaf explants of irr1 mutants. Taken together, these results indicated that IRR1 was involved in AR formation of leaf explants, which was associated with ROS homeostasis to some extent.

The salt-activated CBF1/CBF2/CBF3-GALS1 module fine-tunes galactan-induced salt hypersensitivity in Arabidopsis.

Plant growth and development are significantly hampered in saline environments, limiting agricultural productivity. Thus, it is crucial to unravel the mechanism underlying plant responses to salt stress. ß-1,4-Galactan (galactan), which forms the side chains of pectic rhamnogalacturonan I, enhances plant sensitivity to high-salt stress. Galactan is synthesized by GALACTAN SYNTHASE1 (GALS1). We previously showed that NaCl relieves the direct suppression of GALS1 transcription by the transcription factors BPC1 and BPC2 to induce the excess accumulation of galactan in Arabidopsis (Arabidopsis thaliana). However, how plants adapt to this unfavorable environment remains unclear. Here, we determined that the transcription factors CBF1, CBF2, and CBF3 directly interact with the GALS1 promoter and repress its expression, leading to reduced galactan accumulation and enhanced salt tolerance. Salt stress enhances the binding of CBF1/CBF2/CBF3 to the GALS1 promoter by inducing CBF1/CBF2/CBF3 transcription and accumulation. Genetic analysis suggested that CBF1/CBF2/CBF3 function upstream of GALS1 to modulate salt-induced galactan biosynthesis and the salt response. CBF1/CBF2/CBF3 and BPC1/BPC2 function in parallel to regulate GALS1 expression, thereby modulating the salt response. Our results reveal a mechanism in which salt-activated CBF1/CBF2/CBF3 inhibit BPC1/BPC2-regulated GALS1 expression to alleviate galactan-induced salt hypersensitivity, providing an activation/deactivation fine-tune mechanism for dynamic regulation of GALS1 expression under salt stress in Arabidopsis.

Arabidopsis mitochondrial single-stranded DNA-binding proteins SSB1 and SSB2 are essential regulators of mtDNA replication and homologous recombination.

Faithful DNA replication is one of the most essential processes in almost all living organisms. However, the proteins responsible for organellar DNA replication are still largely unknown in plants. Here, we show that the two mitochondrion-targeted single-stranded DNA-binding (SSB) proteins SSB1 and SSB2 directly interact with each other and act as key factors for mitochondrial DNA (mtDNA) maintenance, as their single or double loss-of-function mutants exhibit severe germination delay and growth retardation. The mtDNA levels in mutants lacking SSB1 and/or SSB2 function were two- to four-fold higher than in the wild-type (WT), revealing a negative role for SSB1/2 in regulating mtDNA replication. Genetic analysis indicated that SSB1 functions upstream of mitochondrial DNA POLYMERASE IA (POLIA) or POLIB in mtDNA replication, as mutation in either gene restored the high mtDNA copy number of the ssb1-1 mutant back to WT levels. In addition, SSB1 and SSB2 also participate in mitochondrial genome maintenance by influencing mtDNA homologous recombination (HR). Additional genetic analysis suggested that SSB1 functions upstream of ORGANELLAR SINGLE-STRANDED DNA-BINDING PROTEIN1 (OSB1) during mtDNA replication, while SSB1 may act downstream of OSB1 and MUTS HOMOLOG1 for mtDNA HR. Overall, our results yield new insights into the roles of the plant mitochondrion-targeted SSB proteins and OSB1 in maintaining mtDNA stability via affecting DNA replication and DNA HR.

Sarracenia purpurea glycerol-3-phosphate acyltransferase 5 confers plant tolerance to high humidity in Arabidopsis thaliana.

Suberin, as a lipid polyester barrier, limits the movement of gas, water, and solutes, and plays important roles in plant protection and growth. In this study, a CDS encoding glycerol-3-phosphate acyltransferase 5 (GPAT5) was cloned from Sarracenia purpurea to investigate the gene function. SpGPAT5 shares 72% identity and 80% similarity to AtGPAT5 that is required for suberin synthesis. Fluorol Yellow 088 staining showed that the S. purpurea pitcher (specific leaf) tube contained more suberin in the adaxial surface compared to the lid, and SpGPAT5 transcripts were detected in the pitcher. Previous reported Atgpat5-1 phenotypes were complemented with SpGPAT5 showing that the Atgpat5-1 seed coat had increased permeability of tetrazolium red and the mutant was sensitive to salt. We also found that SpGPAT5 was able to revert the hyperhydric phenotype of Atgpat5-1 under high humidity. Thus, this study suggests that SpGPAT5 can functionally replace AtGPAT5 and contributes to plant tolerance to high humidity, which maybe assist in understanding the role of suberin-associated waxes in S. purpurea pitchers for water retention.

The Efficacy and Underlying Mechanism of Sulfone Derivatives Containing 1,3,4-oxadiazole on Citrus Canker.

The objectives of the current study were to isolate and identify the pathogen responsible for citrus canker and investigate the efficacy of sulfone derivatives containing 1,3,4-oxadiazole moiety on controlling citrus canker caused by Xanthomonas citri subsp. citri (Xcc) under in vitro and field conditions. In an in vitro study, we tested eight sulfone derivatives against Xcc and the results demonstrated that compound 3 exhibited the best antibacterial activity against Xcc, with a half-maximal effective concentration (EC50) value of 1.23 µg/mL, which was even better than those of commercial bactericides Kocide 3000 (58.21 µg/mL) and Thiodiazole copper (77.04 µg/mL), respectively. Meanwhile, under field experiments, compound 3 treatments demonstrated the highest ability to reduce the disease of citrus canker in leaves and fruits in two different places relative to an untreated control as well as the commercial bactericides Kocide 3000 and Thiodiazole copper. Meanwhile, compound 3 could stimulate the increase in peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia lyase (PAL) activities in the navel orange leaves, causing marked enhancement of plant resistance against citrus canker. Moreover, compound 3 could damage the cell membranes, destruct the biofilm formation, inhibit the production of extracellular polysaccharide (EPS), and affect the cell membrane permeability to restrain the growth of the bacteria.

Quantified difference of the collapsed cone convolution (CCC) and Monte Carlo (MC) algorithms based on DVH and gamma analysis for cervical cancer radiation therapy.

OBJECTIVE: To quantify the difference between the (collapsed cone convolution) CCC algorithm and the (Monte Carlo) MC algorithm and remind that the planners should pay attention to some possible uncertainties of the two algorithms when employing the two algorithms. METHODS: Thirty patients' cervical cancer VMAT plans were designed with a Pinnacle TPS (Philips) and divided equally into two groups: the simple group (SG, target volume was only the PTV) and the complex group (CG, target volume included the PTV and PGTV). The plans from the Pinnacle TPS were transferred to the Monaco TPS (Elekta). The plans' parameters all remained unchanged, and the dose was recalculated. Gamma passing rates (GPRs) obtained from dose distribution from Pinnacle TPS compared with that from Monaco TPS with SNC software based on three triaxial planes (transverse, sagittal and coronal). GPRs and DVH were used to quantify the difference between the CCC algorithm in pinnacle TPS and the MC algorithm in Monaco TPS. RESULTS: Among the statistical dose indexes in DVHs from the Pinnacle and Monaco TPSs, there were 7(7/15) dose indexes difference with statistically significant differences in the SG, and 10(10/18) dose indexes difference with statistically significant differences in the CG. With 3%/3 mm criterion, the most (5/6) GPRs were greater than 95% from the SG and CG. But with 2%/2 mm criterion, the most (5/6) GPRs were less than 90% from the two groups. In addition, we found that GPRs were also related to the selected triaxial planes and the complexity of the plan (GPRs varied with the SG and CG). CONCLUSIONS: Obvious difference between the CCC and MC algorithms from Pinnacle and Monaco TPS. DVH maybe better than 2D gamma analysis on quantifying difference of the CCC and MC algorithms. Some attention should be paid to the uncertainty of the TPS algorithm, especially when the indicator on the DVH is at the critical point of the threshold value, because the algorithm used may overestimate or underestimate the DVH indicator.

Flexible High-Temperature MoS2 Field-Effect Transistors and Logic Gates.

High-temperature-resistant integrated circuits with excellent flexibility, a high integration level (nanoscale transistors), and low power consumption are highly desired in many fields, including aerospace. Compared with conventional SiC high-temperature transistors, transistors based on two-dimensional (2D) MoS2 have advantages of superb flexibility, atomic scale, and ultralow power consumption. However, MoS2 cannot survive at high temperature and drastically degrades above 200 °C. Here, we report MoS2 field-effect transistors (FETs) with top/bottom hexagonal boron nitride (h-BN) encapsulation and graphene electrodes. With the protection of the h-BN/h-BN structure, the devices can survive at much higher temperature (≥500 °C in air) than those of the MoS2 devices ever reported, which provides us an opportunity to explore the electrical properties and working mechanism of MoS2 devices at high temperature. Unlike the relatively low-temperature situation, the on/off ratio and subthreshold swing of MoS2 FETs show drastic variation at elevated temperature due to the injection of thermal emission carriers. Compared with metal electrode, devices with a graphene electrode demonstrate superior performance at high temperature (∼1-order-larger current on/off ratio, 3-7 times smaller subthreshold swing, and 5-9 times smaller threshold voltage shift). We further realize that the flexible CMOS NOT gate based on the above technique, and demonstrate logic computing at 550 °C. This work may stimulate the fundamental research of properties of 2D materials at high temperature, and also creates conditions for next-generation flexible harsh-environment-resistant integrated circuits.

Alpine grassland degradation intensifies the burrowing behavior of small mammals: evidence for a negative feedback loop.

Globally, grassland degradation is an acute ecological problem. In alpine grassland on the Tibetan Plateau, increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal control. However, whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been tested. In this study, we use plateau pika as a model to compare population size, core area of colony, and the number of burrow entrances and latrines between lightly and severely degraded grassland. We test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food abundance. We found that grassland degradation resulted in lower plant species richness, plant height, and biomass. Furthermore, the overall population size of pika was not significantly affected by location in lightly and severely degraded grassland. However, pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and latrines. Our study provides convincing evidence that habitat-induced changes in the behavior of small, burrowing mammals, such as pika, can exacerbate grassland degradation. This finding has significant implications for managing small mammals and restoring degraded grassland ecosystems.

TgLUT1 regulated by TgWRKY10 enhances the tolerance of Torreya grandis to drought stress.

Drought stress is a major abiotic stress which severely reduces the plant growth and limits agricultural productivity. Previous studies have demonstrated that lutein directly synthesized by the carotenoid epsilon-ring hydroxylase gene (LUT1) played crucial roles in regulating drought response. Notwithstanding the myriad studies on LUT1's response to drought stress in certain plant species such as Arabidopsis, the precise function mechanisms within tree species remain ambiguously understood. Our study reveals that under drought stress, TgLUT1, a novel LUT gene instrumental in ß-lutein biosynthesis, was markedly up-regulated in Torreya grandis. Subcellular localization assay indicated that TgLUT1 protein was localized to chloroplasts. Phenotypic analysis showed that overexpression of TgLUT1 enhanced the tolerance of tomato to drought stress. Overexpressing of TgLUT1 increased the values of maximal photochemical efficiency of photosystem II (Fv/Fm), net photosynthetic rate (Pn) and non-photochemical quenching (NPQ), and reduced the accumulation of hydrogen peroxide (H2O2), malondialdehyde (MDA) content and electrolyte leakage percentage in response to drought stress. Furthermore, overexpression of TgLUT1 decreased the stomatal conductance to reduce the water loss rate exposed to drought stress. In addition, yeast one-hybrid assay, dual luciferase assay system and qRT-PCR results showed that TgWRKY10 down-regulated by drought stress inhibited the expression of TgLUT1 by directly binding to the TgLUT1 promoter. Collectively, our results show that TgWRKY10, down-regulated by drought stress, negatively regulates the expression of TgLUT1 to modulate the drought stress response. This study contributes to a more comprehensive understanding of LUT1's function in the stress responses of economically significant forest plants.

Genome-Wide Identification of SPX Family Genes and Functional Characterization of PeSPX6 and PeSPX-MFS2 in Response to Low Phosphorus in Phyllostachys edulis.

Moso bamboo (Phyllostachys edulis) is the most widely distributed bamboo species in the subtropical regions of China. Due to the fast-growing characteristics of P. edulis, its growth requires high nutrients, including phosphorus. Previous studies have shown that SPX proteins play key roles in phosphorus signaling and homeostasis. However, the systematic identification, molecular characterization, and functional characterization of the SPX gene family have rarely been reported in P. edulis. In this study, 23 SPXs were identified and phylogenetic analysis showed that they were classified into three groups and distributed on 13 chromosomes. The analysis of conserved domains indicated that there was a high similarity between PeSPXs among SPX proteins in other species. RNA sequencing and qRT-PCR analysis indicated that PeSPX6 and PeSPX-MFS2, which were highly expressed in roots, were clearly upregulated under low phosphorus. Co-expression network analysis and a dual luciferase experiment in tobacco showed that PeWRKY6 positively regulated the PeSPX6 expression, while PeCIGR1-2, PeMYB20, PeWRKY6, and PeWRKY53 positively regulated the PeSPX-MFS2 expression. Overall, these results provide a basis for the identification of SPX genes in P. edulis and further exploration of their functions in mediating low phosphorus responses.

TgLCYB1 regulated by TgWRKY22 enhances the tolerance of Torreya grandis to waterlogging stress.

ß-Carotene functions in plant growth and development and plays an important role in resisting abiotic stress, such as drought and salt stress. The specific function and mechanism by which ß-carotene responds to waterlogging stress, however, remain elusive. In this study, we found that ß-carotene content and lycopene cyclase (TgLCYB1) expression, both in leaves and roots of Torreya grandis, were increased under waterlogging treatment. Subcellular localization assays indicated that TgLCYB1 was localized in the chloroplasts. Phenotypic, physiological, and metabolome analysis showed that overexpression of TgLCYB1 enhanced the tolerance of tomato plants to waterlogging stress. Furthermore, application of a LCYB enzyme inhibitor, 2-(4-chlorophenylthio)-triethylamine hydrochloride, markedly enhanced the sensitivity of T. grandis to waterlogging stress. In addition, yeast one-hybrid assay, the dual luciferase assay system, and real-time quantitative PCR indicated that waterlogging stress induced TgWRKY22 to increase TgLCYB1 expression by binding to the TgLCYB1 promoter. Collectively, our results indicated that TgWRKY22 positively regulated TgLCYB1 expression to improve the activities of antioxidant enzyme and increase the levels of some key metabolites, thereby relieving waterlogging-induced oxidative damage, and consequently modulating the waterlogging stress response. This study contributes to a more comprehensive understanding of carotenoid functions and the role LCYB genes play in plant stress response.

UBC6, a ubiquitin-conjugating enzyme, participates in secondary cell wall thickening in the inflorescence stem of Arabidopsis.

Secondary cell wall (SCW) thickening in plant inflorescence stems is a complicated cellular process that is essential for stem strength and biomass. Although Arabidopsis NAC transcription factor (TF) 1 (NST1) regulates the SCW thickening in anther walls, the single T-DNA-insertion mutant (nst1) does not show disrupted SCW thickening in anther endothecium, interfascicular fibers or xylem. To better understand the regulatory mechanism of this process, we generated an ethyl methanesulfonate (EMS)-mutagenized Arabidopsis population with the nst1 background. scd5 (SCW-defective mutant 5) was isolated in a forward genetic screen from the EMS mutant library, which displayed not only less lignin deposition in the interfascicular fiber and xylem than the wild type but also a pendent inflorescence stem. The EMS-induced mutation associated with the scd5 phenotype was found in the 5th exon of At2G46030 that encodes a ubiquitin-conjugating enzyme (UBC6), we thereby renamed the allele nst1 ubc6. Overexpressing UBC6 in nst1 ubc6 rescued the defective SCW, whereas disrupting UBC6 in nst1 by the CRISPR/Cas9 system caused a phenotype similar to that observed in nst1 ubc6. UBC6 was localized to the nucleus and plasma membrane, and possessed E2 ubiquitin-conjugating activity in vitro. MYB7 and MYB32 are considered as transcription repressors in the phenylpropanoid pathway and are involved in NAC TF-related transcriptional regulation in SCW thickening. UBC6 can interact with MYB7 and MYB32 and positively mediate the degradation of MYB7 and MYB32 by the 26S proteasome. Overall, these results indicated the contribution of UBC6 to SCW thickening in Arabidopsis inflorescence stems.

CaRH57, a RNA helicase, contributes pepper tolerance to heat stress.

RNA helicases (RHs) are required for most aspects of RNA metabolism and play an important role in plant stress tolerance. Heat stress (HS) causes the deleterious effects on plant cells, such as membrane disruption and protein misfolding, which results in the inhibition of plant growth and development. In this study, CaRH57 was identified from pepper (Capsicum annuum) and encodes a DEAD-box RH. CaRH57 was induced by HS, and overexpression of CaRH57 in Atrh57-1 rescued the glucose-sensitive phenotype of Atrh57-1, suggesting the functional replacement of CaRH57 to AtRH57. The nucleolus-localized CaRH57 possessed a RH activity in vitro. CaRH57 knockdown impaired pepper heat tolerance, showing severe necrosis and enhanced ROS accumulation in the region of the shoot tip. Additionally, accumulation of aberrant-spliced CaHSFA1d and CaHSFA9d was enhanced, and the corresponding mature mRNA levels were reduced in the TRV2 (Tobacco rattle virus)-CaRH57-infected plants compared with the control plants under HS. Overall, these results suggested that CaRH57 acted as a RH to confer pepper heat tolerance and was required for the proper pre-mRNA splicing of some HS-related genes.

Synergistic removal of organic pollutants from water by CTF/BiVO4 heterojunction photocatalysts.

Herein, a series of covalent triazine framework/bismuth vanadate (CTF/BiVO4) heterojunction catalysts were prepared using the hydrothermal method. The mechanism of the CTF/BiVO4 heterojunction photocatalyst in the system was examined to provide a theoretical basis for constructing a high-efficiency photocatalysis composite system for removing organic pollutants from water. Compared with CTF and BiVO4 catalysts alone, composite materials have been shown to have significantly higher degradation efficiencies against organic pollutants in water. Moreover, the degradation effect was found to be optimal when the mass ratio of CTF to BiVO4 was 1:1 (1-CTF/BiVO4). On the basis of physicochemical characterization results, it was concluded that the effective construction of CTF/BiVO4 composite photocatalyst material systems and the formation of type II heterojunction structures between CTF and BiVO4 effectively promote the separation of photogenerated carriers and increase the interface charge transfer efficiency.

Selection of reference genes for quantitative real-time RT-PCR analysis in citrus.

Quantitative real-time reverse transcription polymerase chain reaction (qPCR) has become the preferred method for studying low-abundant mRNA expression. Appropriate application of qPCR in such studies requires the use of reference gene(s) as an internal control in order to normalize the mRNA levels between different samples for an exact comparison of gene expression levels. Expression of the reference gene should be independent from development stage, cell/tissue types, treatments and environmental conditions. Recognizing the importance of reference gene(s) in normalization of qPCR data, various reference genes have been evaluated for stable expression under specific conditions in various organisms. In plants, only a few of them have been investigated, and very few reports about such reference genes in citrus. In the present study, seven candidate reference genes (18SrRNA, ACTB, rpII, UBQI, UBQ10, GAPDH and TUB) were tested, and three of them (18SrRNA, ACTB and rpII) proved to be the most stable ones among six leaf samples of different citrus genotypes. The three candidate reference genes were further analyzed for their stability of expression in five different tissues, and the results indicated that they were not completely stable. It is commonly accepted that gene expression studies should be normalized using more than one reference gene. Based on our results, we propose the use of the mean result rendered by18SrRNA, ACTB and rpII as reference genes to normalize mRNA levels in qPCR analysis of diverse cultivars and tissues of citrus. These results may provide a guideline for future works on gene expression in citrus by using qPCR.

Construction of EGFP-labeling system for visualizing the infection process of Xanthomonas axonopodis pv. citri in planta.

Xanthomonas axonopodis pv. citri (Xac) is the causal agent of citrus bacterial canker, an economically important disease to world citrus industry. To monitor the infection process of Xac in different citrus plants, the enhanced green florescent protein (EGFP) visualizing system was constructed to visualize the propagation and localization in planta. First, the wild-type Xac was isolated from the diseased leaves of susceptible 'Bingtang' sweet orange, and then the isolated Xac was labeled with EGFP by triparental mating. After PCR identification, the growth kinetics and pathogenicity of the transformants were analyzed in comparison with the wild-type Xac. The EGFP-labeled bacteria were inoculated by spraying on the surface and infiltration in the mesophyll of 'Bingtang' sweet orange leaves. The bacterial cell multiplication and diffusion processes were observed directly under confocal laser scanning microscope at different intervals after inoculation. The results indicated that the EGFP-labeled Xac releasing clear green fluorescence light under fluorescent microscope showed the infection process and had the same pathogenicity as the wild type to citrus. Consequently, the labeled Xac demonstrated the ability as an efficient tool to monitor the pathogen infection.

The complete chloroplast genome of Prunus clarofolia (Rosaceae), a wild cherry endemic to China.

Prunus clarofolia (Schneid.) Yu et Li is a very attractive wild flowering cherry endemic to China. In this study, the complete chloroplast genome of P. clarofolia was assembled. The total length of the chloroplast genome was 157,899 bp, containing a pair of inverted repeat regions of 26,393 bp each, separated by a small single-copy region of 19,142 bp, and a large single-copy region of 85,971 bp. The overall GC content of the chloroplast genome was 36.71%. The genome contained 131 genes, including 85 protein-coding genes, 37 tRNA genes, eight rRNA genes, and one pseudogene. Phylogenetic analysis revealed that P. clarofolia and P. pseudocerasus showed the closest relationship.

High-temperature flexible WSe2 photodetectors with ultrahigh photoresponsivity.

The development of high-temperature photodetectors can be beneficial for numerous applications, such as aerospace engineering, military defence and harsh-environments robotics. However, current high-temperature photodetectors are characterized by low photoresponsivity (<10 A/W) due to the poor optical sensitivity of commonly used heat-resistant materials. Here, we report the realization of h-BN-encapsulated graphite/WSe2 photodetectors which can endure temperatures up to 700 °C in air (1000 °C in vacuum) and exhibit unconventional negative photoconductivity (NPC) at high temperatures. Operated in NPC mode, the devices show a photoresponsivity up to 2.2 × 106 A/W, which is ~5 orders of magnitude higher than that of state-of-the-art high-temperature photodetectors. Furthermore, our devices demonstrate good flexibility, making it highly adaptive to various shaped surfaces. Our approach can be extended to other 2D materials and may stimulate further developments of 2D optoelectronic devices operating in harsh environments.

The role of radiotherapy-related autophagy genes in the prognosis and immune infiltration in lung adenocarcinoma.

Background: There is a close relationship between radiotherapy and autophagy in tumors, but the prognostic role of radiotherapy-related autophagy genes (RRAGs) in lung adenocarcinoma (LUAD) remains unclear. Methods: Data used in the current study were extracted from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Weighted gene co-expression network analysis (WGCNA) was executed to recognize module genes associated with radiotherapy. The differentially expressed genes (DEGs) between different radiotherapy response groups were filtered via edgeR package. The differentially expressed radiotherapy-related autophagy genes (DERRAGs) were obtained by overlapping the module genes, DEGs, and autophagy genes (ATGs). Then, prognostic autophagy genes were selected by Cox analyses, and a risk model and nomogram were subsequently built. Gene Set Enrichment Analysis (GSEA) and single-sample Gene Set Enrichment Analysis (ssGSEA) were performed to investigate potential mechanisms through which prognostic autophagy signatures regulate LUAD. Radiotherapy-resistant cell lines (A549IR and PC9IR) were established after exposure to hypo-fractionated irradiation. Ultimately, mRNA expression was validated by quantitative real-time PCR (qRT-PCR), and relative protein levels were measured in different cell lines by western blot. Results: A total of 11 DERRAGs were identified in LUAD. After Cox analyses, SHC1, NAPSA, and AURKA were filtered as prognostic signatures in LUAD. Then, the risk score model was constructed using the prognostic signatures, which had a good performance in predicting the prognosis, as evidenced by receiver operating characteristics curves. Furthermore, Cox regression analyses demonstrated that risk score was deemed as an independent prognostic factor in LUAD. Moreover, GSEA and ssGSEA results revealed that prognostic RRAGs may regulate LUAD by modulating the immune microenvironment and affecting cell proliferation. The colony formation assay showed that the radiosensitivity of radiation-resistant cell lines was lower than that of primary cells. The western blot assay found that the levels of autophagy were elevated in the radiotherapy-resistant cell lines. Moreover, the expression of DERRAGs (SHC1, AURKA) was higher in the radiotherapy-resistant cells than in primary cells. Conclusion: Our study explored the role of RRAGs in the prognosis of LUAD and identified three biomarkers. The findings enhanced the understanding of the relationship between radiotherapy, autophagy, and prognosis in LUAD and provided potential therapeutic targets for LUAD patients.