Diverse Environmental Stresses Research Articles

A systematic analysis of GASA family members in the Salix matsudana genome: Characterization, expression profile, and putative function in antioxidation

The gibberellic acid stimulated Arabidopsis (GASA) gene family, specific to plants, plays a pivotal role in growth, development, and response to diverse environmental stresses. Despite their importance, GASA genes in willow trees have been little studied. Here, 35 SmGASAs were identified from the Salix matsudana genome, which exhibited similar physical and chemical proprieties to GASAs in other species. A phylogenetic analysis revealed that GASAs from Populus trichocarpa, Vitis vinifera, Nicotiana tabacum, Oryza sativa, Arabidopsis thaliana, and S. matsudana are categorized into three distinct subfamilies. It appeared that polyploidization and segmental duplication have contributed to the expansion and diversification of the SmGASA family. These genes were significantly enriched in response to GA and oxygen-containing compounds. The diverse expression patterns observed across willow varieties suggested functional variation of SmGASAs throughout their evolutionary history. The expression profiles of SmGASAs were further analyzed in response to different treatments (i.e., salt, submergence, and polyethylene glycol (PEG)), indicating a potential role for SmGASAs in adapting to these stressors in willows. Remarkably, SmGASAs were shown to detoxify hydrogen peroxide (H2O2), highlighting their potent antioxidant properties. Overall, the comprehensive genomic analysis of willow SmGASAs shed light on their role in stress responses, offering valuable insights for future research and supporting the hypothesis of their involvement in stress adaptation mechanisms.

Vermicompost: A potential organic fertilizer for sustainable vegetable cultivation

Changing climate undermines global food security by adversely affecting crop production. Biological agriculture, or organic farming, serves as an alternative to traditional methods that depend heavily on synthetic inputs. Vermicompost, produced through the non-thermophilic biodegradation of organic waste by earthworms and associated microbes, is a crucial bio-fertilizer that sustainably boosts crop yields and aids in adapting to environmental stresses. Vegetables, a key component of the human diet, provide essential nutrients and combat malnutrition. Grown worldwide under various climatic conditions, vegetables are exposed to diverse environmental stresses that threaten their yield and quality. Applying vermicompost to soil lowers its pH, improves porosity and water retention capacity, enhances microbial activity, and overall soil health. These improvements lead to better germination, growth, development, and yield of vegetable crops. Furthermore, vermicompost protects plants from oxidative stress caused by various abiotic factors by bolstering the antioxidative defense system. This article explores the potential of vermicompost in enhancing the performance of vegetable crops. It examines the impact of different abiotic stresses on vegetables and how vermicompost amendments can mitigate these stresses. Additionally, the study discusses the challenges and opportunities associated with using vermicompost for sustainable vegetable production.

Unraveling the intricacies of cold-inducible RNA-binding protein: A comprehensive review.

Cold-inducible RNA-binding protein (CIRP) is a versatile RNA-binding protein, pivotal in modulating cellular responses to diverse stress stimuli including cold shock, ultraviolet radiation, hypoxia, and infections, with a principal emphasis on cold stress. The temperature range of 32-34°C is most suitable for CIRP expression. The human CIRP is an 18-21kDa polypeptide containing 172 amino acids coded by a gene located on chromosome 19p13.3. CIRP has an RNA-recognition motif (RRM) and an arginine-rich motif (RGG), both of which have roles in coordinating numerous cellular activities. CIRP itself also undergoes conformational changes in response to diverse environmental stress. Transcription factors such as hypoxia-inducible factor 1 alpha and nuclear factor-kappa B have been implicated in coordinating CIRP transcription in response to specific stimuli. The potential of CIRP to relocate from the nucleus to the cytoplasm upon exposure to different stimuli enhances its varied functional roles across different cellular compartments. The different functions include decreasing nutritional demand, apoptosis suppression, modulation of translation, and preservation of cytoskeletal integrity at lower temperatures. This review explores the diverse functions and regulatory mechanisms of CIRP, shedding light on its involvement in various cellular processes and its implications for human health and disease.

Fluorescent chemosensors facilitate the visualization of plant health and their living environment in sustainable agriculture.

Globally, 91% of plant production encounters diverse environmental stresses that adversely affect their growth, leading to severe yield losses of 50-60%. In this case, monitoring the connection between the environment and plant health can balance population demands with environmental protection and resource distribution. Fluorescent chemosensors have shown great progress in monitoring the health and environment of plants due to their high sensitivity and biocompatibility. However, to date, no comprehensive analysis and systematic summary of fluorescent chemosensors used in monitoring the correlation between plant health and their environment have been reported. Thus, herein, we summarize the current fluorescent chemosensors ranging from their design strategies to applications in monitoring plant-environment interaction processes. First, we highlight the types of fluorescent chemosensors with design strategies to resolve the bottlenecks encountered in monitoring the health and living environment of plants. In addition, the applications of fluorescent small-molecule, nano and supramolecular chemosensors in the visualization of the health and living environment of plants are discussed. Finally, the major challenges and perspectives in this field are presented. This work will provide guidance for the design of efficient fluorescent chemosensors to monitor plant health, and then promote sustainable agricultural development.

Advances in Endangered Plant Research: Ammopiptanthus’s Responses to Biotic and Abiotic Stressors

Ammopiptanthus, a unique evergreen broadleaf shrub endemic to the desert regions of Northwest China, exhibits a remarkable capacity for aeolian erosion control and dune stabilization. Attributed to its robust tolerance in terms of xerotolerance, halophytic adaptations, extreme thermotolerance, resistance to biotic and abiotic degradation and its defensive strategies against herbivory, Ammopiptanthus has emerged as an exemplary model organism for the study of plant resilience to diverse environmental stressors. Current research on Ammopiptanthus is scattered, lacking a systematic review, which poses a disadvantage for subsequent in-depth studies and the effective conservation of this endangered resource. In recent years, natural Ammopiptanthus communities have been severely disrupted, and the species’ natural range is rapidly shrinking. Here, this review summarizes the signaling pathways in the Ammopiptanthus response to biotic stress (especially the early signaling events), as well as the research advances in the resistance interactions between biotic and abiotic stresses. Then, the synergistic effects of multiple environmental pressures on Ammopiptanthus could be established, which may provide guidance for further studies on the resistance mechanism of Ammopiptanthus and be beneficial to its natural community protection and reconstruction.

FvMbp1-Swi6 complex regulates vegetative growth, stress tolerance, and virulence in Fusarium verticillioides

The mycotoxigenic fungus Fusarium verticillioides is a common pathogen of grain and medicine that contaminates the host with fumonisin B1 (FB1) mycotoxin, poses serious threats to human and animal health. Therefore, it is crucial to unravel the regulatory mechanisms of growth, and pathogenicity of F. verticillioides. Mbp1 is a component of the MluI cell cycle box binding factor complex and acts as an APSES-type transcription factor that regulates cell cycle progression. However, no information is available regarding its role in F. verticillioides. In this study, we demonstrate that FvMbp1 interacts with FvSwi6 that acts as the cell cycle transcription factor, to form the heteromeric transcription factor complexes in F. verticillioides. Our results show that ΔFvMbp1 and ΔFvSwi6 both cause a severe reduction of vegetative growth, conidiation, and increase tolerance to diverse environmental stresses. Moreover, ΔFvMbp1 and ΔFvSwi6 dramatically decrease the virulence of the pathogen on the stalk and ear of maize. Transcriptome profiling show that FvMbp1-Swi6 complex co-regulates the expression of genes associated with multiple stress responses. These results indicate the functional importance of the FvMbp1-Swi6 complex in the filamentous fungi F. verticillioides and reveal a potential target for the effective prevention and control of Fusarium diseases.

Plastid-expressed AdDjSKI enhances photosystem II stability, delays leaf senescence, and increases fruit yield in tomato plants under heat stress.

Heat stress substantially reduces tomato (Solanum lycopersicum) growth and yield globally, thereby jeopardizing food security. DnaJ proteins, constituents of the heat shock protein system, protect cells from diverse environmental stresses as HSP-70 molecular co-chaperones. In this study, we demonstrated that AdDjSKI, a serine-rich DnaJ III protein induced by pathogens, plays an important role in stabilizing photosystem II (PSII) in response to heat stress. Our results revealed that transplastomic tomato plants expressing the AdDjSKI gene exhibited increased levels of total soluble proteins, improved growth and chlorophyll content, reduced malondialdehyde (MDA) accumulation, and diminished PSII photoinhibition under elevated temperatures when compared with wild-type (WT) plants. Intriguingly, these transplastomic plants maintained higher levels of D1 protein under elevated temperatures compared with the WT plants, suggesting that overexpression of AdDjSKI in plastids is crucial for PSII protection, likely due to its chaperone activity. Furthermore, the transplastomic plants displayed lower accumulation of superoxide radical (O2 •─) and H2O2, in comparison with the WT plants, plausibly attributed to higher superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities. This also coincides with an enhanced expression of corresponding genes, including SlCuZnSOD, SlFeSOD, SlAPX2, and SltAPX, under heat stress. Taken together, our findings reveal that chloroplastic expression of AdDjSKI in tomatoes plays a critical role in fruit yield, primarily through a combination of delayed senescence and stabilizing PSII under heat stress.

Harnessing Phytohormones: Advancing Plant Growth and Defence Strategies for Sustainable Agriculture.

Phytohormones, pivotal regulators of plant growth and development, are increasingly recognized for their multifaceted roles in enhancing crop resilience against environmental stresses. In this review, we provide a comprehensive synthesis of current research on utilizing phytohormones to enhance crop productivity and fortify their defence mechanisms. Initially, we introduce the significance of phytohormones in orchestrating plant growth, followed by their potential utilization in bolstering crop defences against diverse environmental stressors. Our focus then shifts to an in-depth exploration of phytohormones and their pivotal roles in mediating plant defence responses against biotic stressors, particularly insect pests. Furthermore, we highlight the potential impact of phytohormones on agricultural production while underscoring the existing research gaps and limitations hindering their widespread implementation in agricultural practices. Despite the accumulating body of research in this field, the integration of phytohormones into agriculture remains limited. To address this discrepancy, we propose a comprehensive framework for investigating the intricate interplay between phytohormones and sustainable agriculture. This framework advocates for the adoption of novel technologies and methodologies to facilitate the effective deployment of phytohormones in agricultural settings and also emphasizes the need to address existing research limitations through rigorous field studies. By outlining a roadmap for advancing the utilization of phytohormones in agriculture, this review aims to catalyse transformative changes in agricultural practices, fostering sustainability and resilience in agricultural settings.

The centrality of redox regulation and reactive oxygen species sensing in abiotic and biotic stress acclimatization.

During land plant evolution, the number of genes encoding for components of the thiol redox regulatory network and the generator systems of reactive oxygen species (ROS) expanded, tentatively indicating a role in tailored environmental acclimatization. This hypothesis has been validated experimentally and theoretically during the last decades. Recent developments of dynamic roGFP-based in vivo sensors for H2O2 and the redox potential of the glutathione pool paved the way for dissecting the kinetics changes in these decisive parameters in response to environmental stressors. The versatile cellular redox sensory and response regulatory system monitors alterations in redox metabolism and controls the activity of redox target proteins, and thereby affects most, if not all, cellular processes ranging from transcription to translation and metabolism. This review exemplarily describes the role of the redox- and ROS-dependent regulatory network in realising the proper response to diverse environmental stresses. The selected case studies concern different environmental challenges, namely excess excitation energy, the heavy metal cadmium and the metalloid arsenic, nitrogen, or phosphate shortage as examples for nutrient deficiency, wounding, and nematode infestation. Each challenge affects the redox regulatory and ROS network, but the present state of knowledge also pinpoints to pressing open questions concerning the translation of redox regulation to environmental acclimatization.

Transcription Factors and Their Regulatory Roles in the Male Gametophyte Development of Flowering Plants.

Male gametophyte development in plants relies on the functions of numerous genes, whose expression is regulated by transcription factors (TFs), non-coding RNAs, hormones, and diverse environmental stresses. Several excellent reviews are available that address the genes and enzymes associated with male gametophyte development, especially pollen wall formation. Growing evidence from genetic studies, transcriptome analysis, and gene-by-gene studies suggests that TFs coordinate with epigenetic machinery to regulate the expression of these genes and enzymes for the sequential male gametophyte development. However, very little summarization has been performed to comprehensively review their intricate regulatory roles and discuss their downstream targets and upstream regulators in this unique process. In the present review, we highlight the research progress on the regulatory roles of TF families in the male gametophyte development of flowering plants. The transcriptional regulation, epigenetic control, and other regulators of TFs involved in male gametophyte development are also addressed.

Transcriptome- and genome-wide systematic identification of expansin gene family and their expression in tuberous root development and stress responses in sweetpotato (Ipomoea batatas).

Expansins (EXPs) are essential components of the plant cell wall that function as relaxation factors to directly promote turgor-driven expansion of the cell wall, thereby controlling plant growth and development and diverse environmental stress responses. EXPs genes have been identified and characterized in numerous plant species, but not in sweetpotato. In the present study, a total of 59 EXP genes unevenly distributed across 14 of 15 chromosomes were identified in the sweetpotato genome, and segmental and tandem duplications were found to make a dominant contribution to the diversity of functions of the IbEXP family. Phylogenetic analysis showed that IbEXP members could be clustered into four subfamilies based on the EXPs from Arabidopsis and rice, and the regularity of protein motif, domain, and gene structures was consistent with this subfamily classification. Collinearity analysis between IbEXP genes and related homologous sequences in nine plants provided further phylogenetic insights into the EXP gene family. Cis-element analysis further revealed the potential roles of IbEXP genes in sweetpotato development and stress responses. RNA-seq and qRT-PCR analysis of eight selected IbEXPs genes provided evidence of their specificity in different tissues and showed that their transcripts were variously induced or suppressed under different hormone treatments (abscisic acid, salicylic acid, jasmonic acid, and 1-aminocyclopropane-1-carboxylic acid) and abiotic stresses (low and high temperature). These results provide a foundation for further comprehensive investigation of the functions of IbEXP genes and indicate that several members of this family have potential applications as regulators to control plant development and enhance stress resistance in plants.

Rhizobacteria-priming improves common bean seeds germination under different abiotic stresses through improving hydrolysis and antioxidant enzymes kinetics parameters

Bio-priming is a proven method for enhancing seed germination in stressful environments. Researchers have thoroughly explored its impact on enzyme activity during seed germination under diverse environmental stresses. Yet, there is limited knowledge about how bio-priming specifically influences enzyme kinetics. Understanding these kinetic changes could offer valuable insights into the metabolic adjustments and regulatory mechanisms employed by seeds to withstand stress. From this perspective, this study aims to investigate the effects of bio-priming with rhizobacteria on changes in hydrolysis enzymes (amylase and phytase) and antioxidant enzymes (superoxide dismutase and catalase) kinetics in germinated common bean seeds under different abiotic stresses. Two groups of common bean seeds germinated: the first consisted of dry seeds (non-primed), and the second was primed with Bacillus velezensis (bio-primed) under no-stress, drought, salinity, and lead acetate conditions. After 72 h of germination, the germination percentage was recorded. The germinated seeds underwent the extraction and purification of hydrolysis enzymes (amylase and phytase) and antioxidant enzymes (superoxide dismutase and catalase). The kinetic parameters (Michael constant, maximum velocity, turnover number, specificity constant, and catalytic efficiency) for each enzyme were determined. Bio-priming significantly improved common bean germination by enhancing the activity of hydrolysis enzymes and antioxidant enzymes. Enzyme kinetics changes significantly under stress, which indicates that there are differences in the enzyme configuration under stress that induce compounds that can inhibit enzyme activity by increasing the Km and decreasing the Vmax and the enzyme turnover Kcat. On the other hand, bio-priming significantly improved the catalytic efficiency of enzymes by decreasing the Km, increasing the Vmax, and increasing the enzyme turnover (Kcat) under both no-stress and stress conditions.

Divergent adaptation strategies of abundant and rare bacteria to salinity stress and metal stress in polluted Jinzhou Bay

Understanding how abundant (AT) and rare (RT) taxa adapt to diverse environmental stresses is vital for assessing ecological processes, yet remains understudied. We collected sediment samples from Liaoning Province, China, representing rivers (upstream of wastewater outlet), estuaries (wastewater outlets), and Jinzhou Bay (downstream of wastewater outlets), to comprehensively evaluate AT and RT adaptation strategies to both natural stressors (salinity stress) and anthropogenic stressors (metal stress). Generally, RT displayed higher α- and β-diversities and taxonomic groups compared to AT. Metal and salinity stresses induced distinct α-diversity responses in AT and RT, while β-diversity remained consistent. Both subcommunities were dominated by Woeseia genus. Metal stress emerged as the primary driver of diversity and compositional discrepancies in AT and RT. Notably, AT responded more sensitively to salinity stress than RT. Stress increased topological parameters in the biotic network of AT subcommunities while decreasing values in RT subcommunities, concurrently loosening interactions of AT with other taxa and strengthening interactions of RT with others in biotic networks. RT generally exhibited greater diversity of metal resistance genes compared to AT. Greater numbers of genes related to salinity tolerance was observed for the RT than for AT. Compared to AT, RT demonstrated higher diversity of metal resistance genes and a greater abundance of genes associated with salinity tolerance. Additionally, deterministic processes governed AT community assembly, reinforced by salinity stress. However, the opposite trend was observed in the RT, where the importance of stochastic process gradually increased with metal stresses. The study is centered on exploring the adaptation strategies of both AT and RT to environmental stress. It underscores the importance of future research incorporating diverse ecosystems and a range of environmental stressors to draw broader and more reliable conclusions. This comprehensive approach is essential for gaining a thorough understanding of the adaptive mechanisms employed by these microorganisms.

Multiple stressors determine the process of the benthic diatom community assembly and network stability in urban water bodies in Harbin

Human activities have triggered biodiversity loss, often resulting in biotic homogenization, which poses a threat to human well-being. Nevertheless, the overall influence of diverse environmental stressors on intra- and inter-community diversity remains insufficiently elucidated. This study aimed to quantify and reveal the impact of environmental stressors on the alpha and beta diversities of benthic diatom communities in the Harbin urban river network during the summer and autumn of 2022 and spring of 2023. The marked seasonal variations observed in alpha and beta diversity indices highlighted the distinct community compositions. Nonetheless, varying types of urban water pollutants were the primary drivers of biotic homogenization in terms of both taxonomic and functional diversities and played a prominent role in steering diversity shifts. These pollutants indirectly led to biotic homogenization by altering water quality parameters and affecting the ecological dynamics of benthic diatom communities. Furthermore, diverse responses to stressors were identified in taxonomic and functional diversities, providing additional insights for understanding ecological shifts in communities. Taxonomic beta diversity was related to environmental filtering, whereas functional beta diversity resulted from stressor–spatial dimension interactions. Our study emphasises that relying solely on traditional water quality monitoring may not fully reveal the current state of river ecosystem protection, and the need to study the continuous changes in biodiversity across seasons in urban waterbodies from the perspective of various stressors is highlighted.

Jasmonic acid priming augments antioxidant defense and photosynthesis in soybean to alleviate combined heat and drought stress effects

In the aftermaths of global warming, plants are more frequently exposed to the combination of heat stress and drought in natural conditions. Jasmonic acid (JA) has been known to modulate numerous plant adaptive responses to diverse environmental stresses. However, the function of JA in regulating plant responses to the combined effects of heat and drought remains underexplored. In this study, we elucidated the functions of JA in enhancing the combined heat and drought tolerance of soybean (Glycine max). Our results showed that priming with JA improved plant biomass, photosynthetic efficiency and leaf relative water content, which all together contributed to the improved performance of soybean plants under single and combined heat and drought conditions. Exposure to single and combined heat and drought conditions caused oxidative damage in soybean leaves. Priming soybean plants, which were exposed to single and combined heat and drought conditions, with JA, on the other hand, substantially quenched the reactive oxygen species-induced oxidative burden possibly by bolstering their antioxidant defense system. Together, our findings provide direct evidence of the JA-mediated protective mechanisms in maintaining the optimal photosynthetic rate and plant performance under combined heat and drought conditions.

Menstrual pattern and anthropometric characteristics of women with primary and secondary infertility in comparison with age-matched controls

BACKGROUND: The incidence of infertility has increased significantly due to lifestyle changes and the presence of diverse environmental stress. Body mass index (BMI) and waist circumference (WC) are two common anthropometric measures of obesity. Factors such as differences in race, sex, and age influence BMI, and recent studies have reported limitations in the use of BMI to determine obesity. Body fat distribution has a more valid criterion for determining obesity than BMI. Our aim was to compare the menstrual pattern and anthropometric parameters of women with primary and secondary infertility with those of age-matched controls and to assess the correlation between the anthropometric variables and fertility types. MATERIALS AND METHODS: A cross-sectional study was conducted in which the anthropometric measurements and menstrual history over the last 3 months of cases of primary and secondary infertility were compared with the age-matched control group. RESULTS: Women with primary and secondary infertility tend to be overweight or obese. The menstrual pattern of women with infertility was not statistically different as compared to the control groups. There were significant differences in weight, BMI, hip circumference, WC, and neck circumference (NC) of women with primary infertility with those of age-matched controls. A statistically significant difference was noted in NC between the primary and secondary infertility groups. CONCLUSION: The results obtained show that women with infertility tend to be overweight/obese. Due to the limited sample size, the relationship between menstrual pattern and anthropometric characteristics such as waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and frame size (FRS) and infertility could not be established.

Molecular evolution and interaction of 14-3-3 proteins with H+-ATPases in plant abiotic stresses.

Environmental stresses severely affect plant growth and crop productivity. Regulated by 14-3-3 proteins (14-3-3s), H+-ATPases (AHAs) are important proton pumps that can induce diverse secondary transport via channels and co-transporters for the abiotic stress response of plants. Many studies demonstrated the roles of 14-3-3s and AHAs in coordinating the processes of plant growth, phytohormone signaling, and stress responses. However, the molecular evolution of 14-3-3s and AHAs has not been summarized in parallel with evolutionary insights across multiple plant species. Here, we comprehensively review the roles of 14-3-3s and AHAs in cell signaling to enhance plant responses to diverse environmental stresses. We analyzed the molecular evolution of key proteins and functional domains that are associated with 14-3-3s and AHAs in plant growth and hormone signaling. The results revealed evolution, duplication, contraction, and expansion of 14-3-3s and AHAs in green plants. We also discussed the stress-specific expression of those 14-3-3and AHA genes in a eudicotyledon (Arabidopsis thaliana), a monocotyledon (Hordeum vulgare), and a moss (Physcomitrium patens) under abiotic stresses. We propose that 14-3-3s and AHAs respond to abiotic stresses through many important targets and signaling components of phytohormones, which could be promising to improve plant tolerance to single or multiple environmental stresses.

Microbiome variability in invasive coral (Tubastraea aurea) in response to diverse environmental stressors

The Indo-Pacific native azooxanthellate Tubastraea (Scleractinia) has been identified as an invasive marine species with substantial environmental, economic, and social implications worldwide. Despite their exceptional invasive capacity, our understanding of the role of their symbiotic microbiota in host resilience, as well as their response to ambient environmental conditions, remains limited. In this study, we analyzed the symbiotic bacterial communities found in the tissue and mucus of Tubastraea aurea from different habitats along the northeastern coast of Taiwan. These habitats included two extreme sites (a hydrothermal vent [HV] and a copper mining [CM] site) and two normal environments (inlet of a nuclear power plant [NPP] and a habitat adjacent to a conservation zone [CZ]). We employed full-length 16S rRNA sequencing (~1.5 kilobases) to determine coral-associated microbiome responses to local environments. Results showed significant variations in bacterial communities between corals from extreme and normal habitats. Chemoheterotrophic Endozoicomonas bacteria dominated the tissue samples from the HV and CM sites, whereas phototrophic Synechococcus cyanobacteria dominated the NPP and CZ sites. Hydrographic parameters such as pH, salinity, biological oxygen demand, turbidity, and concentration of heavy metals (e.g., Cu and Fe) increased at the HV and CM sites compared with those at the NPP and CZ sites. This difference created more stressful conditions at the HV and CM sites. The microbial assemblages associated with T. aurea exhibited a prevalence of diverse symbiotic bacteria that could potentially contribute to the host’s ability to adapt and survive in challenging ecological conditions. Therefore, these advantageous microorganisms, along with the host’s physiological mechanisms of dispersion, range expansion, and invasiveness, may enhance the resilience and ability of T. aurea to thrive in extreme environments.

Involvement of the heat shock response (HSR) regulatory pathway in cadmium-elicited cerebral damage.

The heat shock response (HSR) is a cellular protective mechanism that is characterized by the induction of heat shock transcription factors (HSFs) and heat shock proteins (HSPs) in response to diverse cellular and environmental stressors, including cadmium (Cd). However, little is known about the relationship between the damaging effects of Cd and the HSR pathway in the chicken cerebrum following Cd exposure. To explore whether Cd exposure elicits cerebral damage and triggers the HSR pathway, chicks were exposed to Cd in the daily diet at different concentrations (35, 70, or 140mg/kg feed) for 90days, while a control group was fed the standard diet without Cd. Histopathological examination of cerebral tissue from Cd-exposed chickens showed neuronal damage, as evidenced by swelling and degeneration of neurons, loss of neurons, and capillary damage. Cd exposure significantly increased mRNA expression of HSF1, HSF2, and HSF3, and mRNA and protein expression of three major stress-inducible HSPs (HSP60, HSP70, and HSP90). Moreover, Cd exposure differentially modulated mRNA expression of small HSP (sHSPs), most notably reducing expression of HSP27 (HSPB1). Furthermore, Cd exposure increased TUNEL-positive neuronal apoptotic cells and up-regulated protein expression of caspase-1, caspase-8, caspase-3, and p53, leading to apoptosis. Taken together, these data demonstrate that activation of the HSR and apoptotic pathways by Cd exposure is involved in Cd-elicited cerebral damage in the chicken. Synopsis for the graphical abstract Cadmium (Cd)-induced neuronal damage triggers the heat shock response (HSR) by activating heat shock transcription factors (HSFs) and subsequent induction of major heat shock proteins (notably, HSP60, HSP70, and HSP90). Moreover, Cd exposure activates caspase-1, caspase-8, caspase-3, and p53 protein, thereby resulting in neuronal apoptosis in the chicken brain.

Identification of ARF transcription factor gene family and its defense responses to bacterial infection and salicylic acid treatment in sugarcane.

Auxin response factor (ARF) is a critical regulator in the auxin signaling pathway, involved in a variety of plant biological processes. Here, gene members of 24 SpapARFs and 39 SpnpARFs were identified in two genomes of Saccharum spontaneum clones AP85-441 and Np-X, respectively. Phylogenetic analysis showed that all ARF genes were clustered into four clades, which is identical to those ARF genes in maize (Zea mays) and sorghum (Sorghum bicolor). The gene structure and domain composition of this ARF family are conserved to a large degree across plant species. The SpapARF and SpnpARF genes were unevenly distributed on chromosomes 1-8 and 1-10 in the two genomes of AP85-441 and Np-X, respectively. Segmental duplication events may also contribute to this gene family expansion in S. spontaneum. The post-transcriptional regulation of ARF genes likely involves sugarcane against various stressors through a miRNA-medicated pathway. Expression levels of six representative ShARF genes were analyzed by qRT-PCR assays on two sugarcane cultivars [LCP85-384 (resistant to leaf scald) and ROC20 (susceptible to leaf scald)] triggered by Acidovorax avenae subsp. avenae (Aaa) and Xanthomonas albilineans (Xa) infections and salicylic acid (SA) treatment. ShARF04 functioned as a positive regulator under Xa and Aaa stress, whereas it was a negative regulator under SA treatment. ShARF07/17 genes played positive roles against both pathogenic bacteria and SA stresses. Additionally, ShARF22 was negatively modulated by Xa and Aaa stimuli in both cultivars, particularly LCP85-384. These findings imply that sugarcane ARFs exhibit functional redundancy and divergence against stressful conditions. This work lays the foundation for further research on ARF gene functions in sugarcane against diverse environmental stressors.