Light Response Research Articles

Visible-light photoelectric performance and bending stability of flexible LaCoO3/Mica thin films

New energy sources such as solar energy have been developed and utilized due to the shortage of non-renewable energy, and photoelectric materials have attracted more attention, accordingly. Moreover, flexible optoelectronic devices are crucial in the fields of wearable artificial intelligence, portable energy, and smart medical care. At present, photoelectric devices based on traditional perovskite cobalt oxide rigid films have problems such as inability to bend and deformation, which limits their application environment. Here, natural mica with atomically flat surface, high thermal stability, high transparency and good mechanical flexibility was selected as the substrate for preparing a series of LaCoO3 flexible photoelectric films. These films exhibit excellent photoelectric properties and flexible properties. More importantly, the flexible film still has fast response speed and reproducible light response after 500 bending cycles. It reveals that all-inorganic perovskite LaCoO3 is a promising candidate for designing high-performance, flexible and wearable optoelectronic devices.

Oxygen vacancies nanoarchitectonics in BiVO4/WO3 heterostructured photoanode for effective berberine wastewater purification and electricity generation

BackgroundPhotoanode, as a key component of the photocatalytic fuel cell, still faces challenges for high-efficiency wastewater treatment and synchronous electricity generation, owing to low electron-hole separation efficiency and light response. MethodsOxygen vacancies were rationally introduced on BiVO4/WO3 (OV-BiVO4/WO3) as visible-light-responsive photoanode, through a simple two-step hydrothermal method. The favorable activities were primarily derived from the synergistic effects of the oxygen vacancies and heterojunction, which extended the light adsorption range and significantly improved the separation ability of photogenerated carriers, revealing by comprehensive experiments and theoretical calculations. Significant FindingsCompared with WO3, BiVO4 and BiVO4/WO3, OV-BiVO4/WO3 exhibited highest berberine degradation rate (97.7 %, 120 min) and maximum power density (0.42 mW cm−2). Further, the influence of water conditions on photocatalytic performance was explored considering the complexity of actual wastewater. The findings evidenced that ·OH and ·O2− mainly participated in antibiotic decomposition. The photocatalytic reaction mechanism and berberine degradation pathway over OV-BiVO4/WO3 were proposed. This study emphasizes the importance of oxygen vacancies engineering controlling over the surface catalytic performance of photoelectrode and electricity generation, and illustrates the potential of for water remediation and energy production.

Resource utilization of MSWI fly ash supporting TiO2/BiOCl nanocomposite for enhanced photocatalytic degradation of sodium isopropyl xanthate: Mechanism and performance evaluation

The removal of organic pollutants in water environments and the resource utilization of solid waste are two pressing issues around the world. Facing the increasing pollution induced by discharge of mining effluents containing sodium isopropyl xanthate (SIPX), in this work, municipal solid waste incineration fly ash (MSWI FA) was pretreated by hydrothermal method to produce stabilized FA, which was then innovatively used as support for the construction of FA/TiO2/BiOCl nanocomposite (FTB) with promoted photocatalytic activity under visible light and natural sunlight. When the content of FA was 20 wt% and the mass ratio of TiO2 to BiOCl was 4:6, a remarkable performance for the optimal FTB (20-FTB-2) was achieved. Characterizations demonstrated that TiO2 and BiOCl uniformly dispersed on FA contributing to high surface area and broad light adsorption of FTB, which exhibits excellent adsorption capacity and light response ability. Build in electric field formed in the interface of TiO2/BiOCl heterojunction revealed by density functional theory calculations accelerated the separation of photoinduced e− and h+, leading to high efficiency for SIPX degradation. The synergetic effect combined with adsorption and photocatalytic degradation endowed 20-FTB-2 superior SIPX removal efficiency over 99% within 30 min under visible light and natural sunlight irradiation. The photocatalytic degradation pathways of SIPX were determined through theoretical calculations and characterizations, and the toxic byproduct CS2 was effectively eliminated through oxidation of •O2−. For 20-FTB-2, reusability of photocatalyst was showed by cycle tests, also the concentrations of main heavy metals (Pb, Zn, Cu, Cr, and Cd) in the liquid phases released during photocatalyst preparation process (< 1 mg/L) and photodegradation process (< 8.5 μg/L) proved the satisfactory stability with low toxicity. This work proposed a novel strategy to develop efficient and stable support-based photocatalysts by utilizing MSWI FA and realize its resource utilization.

Bloom dynamics under the effects of periodic driving forces

Phytoplankton bloom received considerable attention for many decades. Different approaches have been used to explain the bloom phenomena. In this paper, we study a Nutrient–Phytoplankton–Zooplankton (NPZ) model consisting of a periodic driving force in the growth rate of phytoplankton due to solar radiation and analyse the dynamics of the corresponding autonomous and non-autonomous systems in different parametric regions. Then we introduce a novel aspect to extend the model by incorporating another periodic driving force into the growth term of the phytoplankton due to sea surface temperature (SST), a key point of innovation. Temperature dependency of the maximum growth rate (μmax) of the phytoplankton is modelled by the well-known Q10 formulation: μmax=μ0∗(Q10)T/10, where μ0 is maximum growth at 0oC. Stability conditions for all three equilibrium points are expressed in terms of the new parameter ρ2, which appears due to the incorporation of periodic driving forces. System dynamics is explored through a detailed bifurcation analysis, both mathematically and numerically, with respect to the light and temperature dependent phytoplankton growth response. Bloom phenomenon is explained by the saddle point bloom mechanism even when the co-existing equilibrium point does not exist for some values of ρ2. Solar radiation and SST are modelled using sinusoidal functions constructed from satellite data. Our results of the proposed model describe the initiation of the phytoplankton bloom better than an existing model for the region 25–35° W, 40–45° N of the North Atlantic Ocean. An improvement of 14 days (approximately) is observed in the bloom initiation time. The rate of change method (ROC) is applied to predict the bloom initiation.

Constructing S‐scheme heterojunctions with tunable interfacial oxygen vacancy via UiO‐66‐NH2‐derived ZrO2‐x for efficient photocatalytic performance

Defects engineering is significant for photocatalytic environment remediation. To this end, visible‐light‐driven α‐Fe2O3/ZrO2‐x S‐scheme heterojunction photocatalysts with optimal oxygen vacancy (Ov) defects are successfully synthesized via a two‐step method. Compared with pristine UiO‐66‐NH2‐derived ZrO2‐x and α‐Fe2O3, the heterojunction photocatalysts exhibit a wider range of visible light response and higher efficiency in separating photogenerated electron–hole pairs. Among them, the 5% α‐Fe2O3/ZrO2‐x sample shows the best photocatalytic performance to the degradation of tetracycline (TC) (89.3%), in which the pseudo‐first‐order kinetic rate constants are 8.20 and 16.75 times that of pristine ZrO2‐x and α‐Fe2O3, respectively. The outstanding photocatalytic degradation efficiency can be attributed to both the narrow‐bandgap ZrO2‐x with visible light response and the formation of α‐Fe2O3/ZrO2‐x S‐scheme heterojunctions. During the formation of heterojunctions, the concentration of oxygen vacancies (Ov) at the interface of α‐Fe2O3/ZrO2‐xdecreases monotonically with the increasing loading of α‐Fe2O3, thereby altering the electronic structure of the photocatalyst and forming the heterojunction firmly. In addition, the high stability implies the potential applications in fields of environment.

Estimation of global ecosystem isohydricity from solar-induced chlorophyll fluorescence and meteorological datasets

Plants exhibit varying strategies for optimizing the trade-off between CO2 uptake and water loss through transpiration in response to increasing air or soil dryness. Anisohydric plants generally keep their stomata open to maintain or enhance carbon uptake, but this exposes them to a greater risk of hydraulic failure. In contrast, isohydric plants tend to maintain hydraulic integrity by enforcing stricter stomatal and xylem regulation, albeit at the expense of reduced carbon assimilation. Information on the degree of ecosystem isohydricity (σ) is important for predicting plant mortality during drought. However, the current σ estimation method lacks a physiological basis by not explicitly accounting for the photosynthesis process. Recent advances in observing solar-induced chlorophyll fluorescence (SIF), an effective proxy for photosynthetic rate, provides new potential to estimate σ at regional and global scales. Based on the revised mechanistic light response (rMLR) model, we developed a mechanistic, SIF-based model of ecosystem-scale isohydricity forced by satellite SIF observations and meteorological datasets. This model was used to estimate daily global ecosystem isohydricity from 2019 to 2020 at a spatial resolution of 0.25°. During the study period, the mean ecosystem isohydricity of global ecosystems was 0.75, suggesting that, on the whole, global terrestrial ecosystems tend to exhibit more anisohydric behavior. Specifically, herbaceous vegetation mostly displaying highly anisohydric behavior, while woody vegetation tended to be more isohydric. Ecosystem isohydricity exhibits clear seasonality, becoming more isohydric in summer. A random-forest analysis revealed that the three most important factors influencing global ecosystem isohydricity are net photosynthesis rate (Anet), canopy height (h), and vapor pressure deficit (VPD), which collectively accounted for 86.1% of the importance. We also found that ecosystem isohydricity reflects a plant-environment interaction, with the contribution of intrinsic hydraulic traits likely exceeding 50%. The proposed model enables us to incorporate plant physiological controls into the estimation of ecosystem-scale σ, thereby enhancing our ability to track plant water-use strategies in response to rising water stress in a changing climate.

Genome-wide characterization and expression profiling of the HD-ZIP gene family in Acoraceae under salinity and cold stress.

The Homeodomain-Leucine Zipper (HD-ZIP) transcription factors play a pivotal role in governing various aspects of plant growth, development, and responses to abiotic stress. Despite the well-established importance of HD-ZIPs in many plants, their functions in Acoraceae, the basal lineage of monocots, remain largely unexplored. Using recently published whole-genome data, we identified 137 putative HD-ZIPs in two Acoraceae species, Acorus gramineus and Acorus calamus. These HD-ZIP genes were further classified into four subfamilies (I, II, III, IV) based on phylogenetic and conserved motif analyses, showcasing notable variations in exon-intron patterns among different subfamilies. Two microRNAs, miR165/166, were found to specifically target HD-ZIP III genes with highly conserved binding sites. Most cis-acting elements identified in the promoter regions of Acoraceae HD-ZIPs are involved in modulating light and phytohormone responsiveness. Furthermore, our study revealed an independent duplication event in Ac. calamus and a one-to-multiple correspondence between HD-ZIP genes of Ac. calamus and Ac. gramineus. Expression profiles obtained from qRT-PCR demonstrated that HD-ZIP I genes are strongly induced by salinity stress, while HD-ZIP II members have contrasting stress responses in two species. HD-ZIP III and IV genes show greater sensitivity in stress-bearing roots. Taken together, these findings contribute valuable insights into the roles of HD-ZIP genes in stress adaptation and plant resilience in basal monocots, illuminating their multifaceted roles in plant growth, development, and response to abiotic stress.

Shape Memory Polyurethane Composite With Fast Response to Near-Infrared Light Based on Tannic Acid-Iron and Dynamic Phenol-Carbamate Network.

Intelligent materials derived from green and renewable bio-based materials garner widespread attention recently. Herein, shape memory polyurethane composite (PUTA/Fe) with fast response to near-infrared (NIR) light is successfully prepared by introducing Fe3+ into the tannic acid-based polyurethane (PUTA) matrix through coordination between Fe3+ and tannic acid. The results show that the excellent NIR light response ability is due to the even distribution of Fe3+ filler with good photo-thermal conversion ability. With the increase of Fe3+ content, the NIR light response shape recovery rate of PUTA/Fe composite films is significantly improved, and the shape recovery time is reduced from over 60 s to 40s. In addition, the mechanical properties of PUTA/Fe composite film are also improved. Importantly, owing to the dynamic phenol-carbamate network within the polymer matrix, the PUTA/Fe composite film can reshape its permanent shape through topological rearrangement and show its good NIR light response shape memory performance. Therefore, PUTA/Fe composites with high content of bio-based material (TA content of 15.1-19.4%) demonstrate the shape memory characteristics of fast response to NIR light; so, it will have great potential in the application of new intelligent materials including efficient and environmentally friendly smart photothermal responder.

Implementation of bridged copolymerisation to optimise the optical properties of porphyrin: applications in dye-sensitized solar cells

This study explores the concept of all-organic sensitisation of dye-sensitized solar cells (DSSCs) by using a cosensitization approach to model efficient porphyrin-based photosensitizers. The aim is to enhance the absorption defects and light response current of porphyrin dyes, which have been reported in the literature. In this work, eight (8) natural porphyrin derivatives obtained through bridged copolymerisation of free base porphyrin and tetraazaporphyrin have been modelized and analysed. Their geometric parameters, stability energies, chemical stabilities, and photochemical properties were studied using density functional theory (DFT) methods in both gaseous and dichloromethane (DCM) phases. The analysis of photochemical properties, including maximum absorption wavelength ( λ max ), light harvesting efficiency (LHE), electron injection driving force ( Δ G inj ), regeneration driving force ( Δ G reg ), and excited state lifetime ( τ ) of the studied photosensitizers, show significant improvement compared to the parent dye (free base porphyrin) and some recent derivatives SM315 and YD2-o-C8. It is worth noting that the eight ( 8 ) modelled dyes from porphyrin show broader LHE curves not only compared to the parent dye, but also compared to the SM315 dye, which may lead to a higher running photo density. This study highlights the effectiveness of bridged copolymerisation for developing high-performance DSSCS based on porphyrin.

[Uncovering the molecular mechanisms behind steroidal saponin accumulation in Liriope muscari (Decne.) Baily through transcriptome sequencing and bioinformatics analysis].

The leaves and roots of Liriope muscari (Decne.) Baily were subjected to high-throughput Illumina transcriptome sequencing. Bioinformatics analysis was used to investigate the enzyme genes and key transcription factors involved in regulating the accumulation of steroidal saponins, which are the main active ingredient in L. muscari. These analyses aimed to reveal the molecular mechanism behind steroidal saponin accumulation. The sequencing results of L. muscari revealed 31 enzymes, including AACT, CAS, DXS and DXR, that are involved in the synthesis of steroidal saponins. Among these enzymes, 16 were in the synthesis of terpenoid skeleton, 3 were involved in the synthesis of sesquiterpene and triterpene, and 12 were involved in the synthesis of steroidal compound. Differential gene expression identified 15 metabolic enzymes coded by 34 differentially expressed genes (DEGs) in the leaves and roots, which were associated with steroidal saponin synthesis. Further analysis using gene co-expression patterns showed that 14 metabolic enzymes coded by 31 DEGs were co-expressed. In addition, analysis using gene co-expression analysis and PlantTFDB's transcription factor analysis tool predicted the involvement of 8 transcription factors, including GAI, PIF4, PIL6, ERF8, SVP, LHCA4, NF-YB3 and DOF2.4, in regulating 6 metabolic enzymes such as DXS, DXR, HMGR, DHCR7, DHCR24, and CAS. These eight transcription factors were predicted to play important roles in regulating steroidal saponin accumulation in L. muscari. Promoter analysis of these transcription factors indicated that their main regulatory mechanisms involve processes such as abscisic acid response, drought-induction stress response and light response, especially abscisic acid responsive elements (ABRE) response and MYB binding site involved in drought-inducibility (MBS) response pathway. Furthermore, qRT-PCR analysis of these eight key transcription factors demonstrated their specific differences in the leaves and roots.

Circadian rhythm response and its effect on photosynthetic characteristics of the Lhcb family genes in tea plant

BackgroundThe circadian clock, also known as the circadian rhythm, is responsible for predicting daily and seasonal changes in the environment, and adjusting various physiological and developmental processes to the appropriate times during plant growth and development. The circadian clock controls the expression of the Lhcb gene, which encodes the chlorophyll a/b binding protein. However, the roles of the Lhcb gene in tea plant remain unclear.ResultsIn this study, a total of 16 CsLhcb genes were identified based on the tea plant genome, which were distributed on 8 chromosomes of the tea plant. The promoter regions of CsLhcb genes have a variety of cis-acting elements including hormonal, abiotic stress responses and light response elements. The CsLhcb family genes are involved in the light response process in tea plant. The photosynthetic parameter of tea leaves showed rhythmic changes during the two photoperiod periods (48 h). Stomata are basically open during the day and closed at night. Real-time quantitative PCR results showed that most of the CsLhcb family genes were highly expressed during the day, but were less expressed at night.ConclusionsResults indicated that CsLhcb genes were involved in the circadian clock process of tea plant, it also provided potential references for further understanding of the function of CsLhcb gene family in tea plant.

In silico analysis of the wheat BBX gene family and identification of candidate genes for seed dormancy and germination

BackgroundB-box (BBX) proteins are a type of zinc finger proteins containing one or two B-box domains. They play important roles in development and diverse stress responses of plants, yet their roles in wheat remain unclear.ResultsIn this study, 96 BBX genes were identified in the wheat genome and classified into five subfamilies. Subcellular localization prediction results showed that 68 TaBBXs were localized in the nucleus. Protein interaction prediction analysis indicated that interaction was one way that these proteins exerted their functions. Promoter analysis indicated that TaBBXs may play important roles in light signal, hormone, and stress responses. qRT-PCR analysis revealed that 14 TaBBXs were highly expressed in seeds compared with other tissues. These were probably involved in seed dormancy and germination, and their expression patterns were investigated during dormancy acquisition and release in the seeds of wheat varieties Jing 411 and Hongmangchun 21, showing significant differences in seed dormancy and germination phenotypes. Subcellular localization analysis confirmed that the three candidates TaBBX2-2 A, TaBBX4-2 A, and TaBBX11-2D were nuclear proteins. Transcriptional self-activation experiments further demonstrated that TaBBX4-2A was transcriptionally active, but TaBBX2-2A and TaBBX11-2D were not. Protein interaction analysis revealed that TaBBX2-2A, TaBBX4-2A, and TaBBX11-2D had no interaction with each other, while TaBBX2-2A and TaBBX11-2D interacted with each other, indicating that TaBBX4-2A may regulate seed dormancy and germination by transcriptional regulation, and TaBBX2-2A and TaBBX11-2D may regulate seed dormancy and germination by forming a homologous complex.ConclusionsIn this study, the wheat BBX gene family was identified and characterized at the genomic level by bioinformatics analysis. These observations provide a theoretical basis for future studies on the functions of BBXs in wheat and other species.

Microstructure regulation of Zn0.5Cd0.5S for enhancing the photocatalytic H2 production

As an excellent photocatalytic material, ZnxCd1-xS is widely used in photocatalytic H2 production due to its good visible light response and suitable band position. Based on our previous studies, this paper systematically studies the relationship of Zn0.5Cd0.5S (ZCS) material between microstructure and photocatalytic activity. By controlling the synthesized temperature, S sources and solvents, a series of ZCS nanomaterials with different morphology and crystalline phase have been prepared by hydrothermal, solvothermal and ion-exchange methods. When several sacrificial agents are added in photocatalytic H2 production, ZCS performs the highest activity synthesized by solvothermal method, about 12.15 mmol g−1 under 4 h’s visible light illumination. To explore the difference of ZCS samples in photocatalytic performance, many factors are considered, such as crystal size, crystallinity, separation of photogenerated charge carriers (PCCs), specific surface area and defect sites, which play important roles in the improving photocatalytic activity. This work provides a new direction for the design of photocatalyst from the microstructural regulation to achieve highly efficient activity.

Construction of Zn0.5Cd0.5S/Bi4O5Br2 Heterojunction for Enhanced Photocatalytic Degradation of Tetracycline Hydrochloride

The development of efficient catalysts with visible light response for the removal of pollutants in an aqueous environment has been a hotspot in the field of photocatalysis research. A Zn0.5Cd0.5S (ZCS) nanoparticle/Bi4O5Br2 ultra-thin nanosheet heterojunction was constructed by ultrasound-assisted solvothermal method. The morphology, structure, and optoelectronic properties of the composite were characterized by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectra. Under simulated visible light illumination, the photocatalytic performance was evaluated through degradation of tetracycline hydrochloride. Results show that the degradation effect by the optimum ZCS/Bi4O5Br2 catalyst is superior to pure materials with the kinetic constant that is 1.7 and 9.6 times higher than those of Bi4O5Br2 and ZCS, and also has better stability and reusability. Trapping experiments and electron paramagnetic resonance tests find that free radicals in the photocatalytic system are superoxide radicals and holes. This work provides a referable idea for the development of more efficient and recyclable photocatalysts.

Genome-Wide Identification of Phytochrome-Interacting Factor (PIF) Gene Family in Potatoes and Functional Characterization of StPIF3 in Regulating Shade-Avoidance Syndrome

The phytochrome-interacting factor (PIF) proteins are part of a subfamily of basic helix–loop–helix (bHLH) transcription factors that integrate with phytochromes (PHYs) and are known to play important roles in adaptive changes in plant architecture. However, the characterization and function of PIFs in potatoes are currently poorly understood. In this study, we identified seven PIF members in potatoes and named them StPIF01-1, StPIF01-2, StPIF03, StPIF06-1, StPIF06-2, StPIF07, and StPIF09 based on their location in potato chromosomes. The chromosomal location, gene structures, physicochemical characteristics, phylogenetic tree, and tissue-specific expression of StPIFs were also analyzed. RT-qPCR analysis revealed that the StPIF3 gene was highly induced by shade and may play a crucial regulatory role in potato responses to shade stress. Also, multiple cis-regulatory elements involved in light response were detected in the promoter of the StPIF genes. Subcellular localization analysis indicated that the StPIF3-encoding protein is mainly localized in the nucleus. Transgenic overexpression of StPIF3 in potatoes increased stem length, chlorophyll accumulation, and enhanced shade-avoidance symptoms, whereas the StPIF3-interfering lines had a lower plant height and more chlorophyll accumulation. These findings enhance our comprehension of StPIF gene roles, potentially advancing potato yield and quality research. This study provides detailed information about StPIFs and identifies the function of StPIF3, which is involved in shade-avoidance syndrome.

Synergistic strategies of metallization and redox coupling to enhance the quantum yield and recyclability of porphyrin COF

Enhancing the quantum efficiency of photocatalytic reactions and recyclability of photocatalysts are crucial for the practical applications of photocatalytic technology. In this study, a mechanical grinding method was employed to prepare porphyrin covalent organic framework (Por-COF) and metalloporphyrin covalent organic frameworks (MPor-COF, M = Zn, Fe). These COFs were evaluated for their photocatalytic and recycling performances under visible light. ZnPor-COF exhibited a significant enhancement in quantum efficiency compared to Por-COF, with efficiency increases of 31.8 %, 3.0 %, and 11.5 % for individual reduction, individual oxidation, and simultaneous redox reactions, respectively. Notably, when ZnPor-COF underwent simultaneous redox reactions with oxidation and reduction efficiencies above 80 %, the number of recycles increased from 3 to 10 times compared to Por-COF. This synergistic strategy of metallization and redox coupling improved the photocatalytic and recycling performance of Por-COF. Experimental and theoretical investigations revealed that the introduction of metal ions enhance light response, altere energy levels, reduce carrier separation distance, and improve carrier separation performance. Simultaneous oxidation and reduction reactions effectively mitigated photocorrosion, enhancing stability and carrier utilization efficiency. This research provides valuable insights for advancing porphyrin-based COF photocatalytic technology.

Effect of lattice water on the photochromic property/photochromism of a Zn(II)-viologen coordination polymers

Electron transfer is crucial for the rapid response of viologen-based complexes and investigating the factors that affect electron transfer has always been a major challenge. Herein, a new viologen-based complex, formulated as {[Zn5(cbbbc)3(BTC)3(μ1,1-OH)(H2O)5]·22H2O}n, with a three-dimensional framework was successfully designed and synthesized by viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium chloride (Hcbbpy), trimesic acid (H3BTC) and Zn(NO3)2·6H2O. In particular, complex 1 does not exhibit photochromic properties. However, samples of complex 1 heated at 120 and 180 ℃ display tunable colors under UV light irradiation. The experimental results indicate that the compound's light response is less sensitive with higher water content in the lattice. The polarity and hydrogen bonding ability of lattice water in viologen-based complexes can interact with the donor of viologen, leading to a reduction in electron transfer. This study demonstrates the impact of lattice water on electron transfer in viologen-based complexes and offers insights for designing faster response complexes in the future.

Genome-Wide Analysis of the HSF Gene Family Reveals Its Role in Astragalus mongholicus under Different Light Conditions.

Astragalus mongholicus is a traditional Chinese medicine (TCM) with important medicinal value and is widely used worldwide. Heat shock (HSF) transcription factors are among the most important transcription factors in plants and are involved in the transcriptional regulation of various stress responses, including drought, salinity, oxidation, osmotic stress, and high light, thereby regulating growth and developmental processes. However, the HFS gene family has not yet been identified in A. mongholicus, and little is known regarding the role of HSF genes in A. mongholicus. This study is based on whole genome analysis of A. mongholicus, identifying a total of 22 AmHSF genes and analyzing their physicochemical properties. Divided into three subgroups based on phylogenetic and gene structural characteristics, including subgroup A (12), subgroup B (9), and subgroup C (1), they are randomly distributed in 8 out of 9 chromosomes of A. mongholicus. In addition, transcriptome data and quantitative real time polymerase chain reaction (qRT-PCR) analyses revealed that AmHSF was differentially transcribed in different tissues, suggesting that AmHSF gene functions may differ. Red and blue light treatment significantly affected the expression of 20 HSF genes in soilless cultivation of A. mongholicus seedlings. AmHSF3, AmHSF3, AmHSF11, AmHSF12, and AmHSF14 were upregulated after red light and blue light treatment, and these genes all had light-corresponding cis-elements, suggesting that AmHSF genes play an important role in the light response of A. mongholicus. Although the responses of soilless-cultivated A. mongholicus seedlings to red and blue light may not represent the mature stage, our results provide fundamental research for future elucidation of the regulatory mechanisms of HSF in the growth and development of A. mongholicus and its response to different light conditions.

Systematic Analysis of DNA Demethylase Gene Families in Foxtail Millet (Setaria italica L.) and Their Expression Variations after Abiotic Stresses.

DNA methylation is a highly conserved epigenetic modification involved in many biological processes, including growth and development, stress response, and secondary metabolism. DNA demethylase (DNA-deMTase) genes have been identified in some plant species; however, there are no reports on the identification and analysis of DNA-deMTase genes in Foxtail millet (Setaria italica L.). In this study, seven DNA-deMTases were identified in S. italica. These DNA-deMTase genes were divided into four subfamilies (DML5, DML4, DML3, and ROS1) by phylogenetic and gene structure analysis. Further analysis shows that the physical and chemical properties of these DNA-deMTases proteins are similar, contain the typical conserved domains of ENCO3c and are located in the nucleus. Furthermore, multiple cis-acting elements were observed in DNA-deMTases, including light responsiveness, phytohormone responsiveness, stress responsiveness, and elements related to plant growth and development. The DNA-deMTase genes are expressed in all tissues detected with certain tissue specificity. Then, we investigated the abundance of DNA-deMTase transcripts under abiotic stresses (cold, drought, salt, ABA, and MeJA). The results showed that different genes of DNA-deMTases were involved in the regulation of different abiotic stresses. In total, our findings will provide a basis for the roles of DNA-deMTase in response to abiotic stress.

Transcriptomic analysis of hub genes regulating albinism in light- and temperature-sensitive albino tea cultivars 'Zhonghuang 1' and 'Zhonghuang 2'.

Albino tea cultivars have high economic value because their young leaves contain enhanced free amino acids that improve the quality and properties of tea. Zhonghuang 1 (ZH1) and Zhonghuang 2 (ZH2) are two such cultivars widely planted in China; however, the environmental factors and molecular mechanisms regulating their yellow-leaf phenotype remain unclear. In this study, we demonstrated that both ZH1 and ZH2 are light- and temperature-sensitive. Under natural sunlight and low-temperature conditions, their young shoots were yellow with decreased chlorophyll and an abnormal chloroplast ultrastructure. Conversely, young shoots were green with increased chlorophyll and a normal chloroplast ultrastructure under shading and high-temperature conditions. RNA-seq analysis was performed for high light and low light conditions, and pairwise comparisons identified genes exhibiting different light responses between albino and green-leaf cultivars, including transcription factors, cytochrome P450 genes, and heat shock proteins. Weighted gene coexpression network analyses of RNA-seq data identified the modules related to chlorophyll differences between cultivars. Genes involved in chloroplast biogenesis and development, light signaling, and JA biosynthesis and signaling were typically downregulated in albino cultivars, accompanied by a decrease in JA-ILE content in ZH2 during the albino period. Furthermore, we identified the hub genes that may regulate the yellow-leaf phenotype of ZH1 and ZH2, including CsGDC1, CsALB4, CsGUN4, and a TPR gene (TEA010575.1), which were related to chloroplast biogenesis. This study provides new insights into the molecular mechanisms underlying leaf color formation in albino tea cultivars.