Hypothermia Research Articles

Study on the changes of miRNAs and their target genes in regulating anthocyanin synthesis during purple discoloration of cauliflower curd under low temperature stress

IntroductionCauliflower is widely cultivated all over the world is attributed to its palatable flavor, high levels of anti-cancer compounds, and diverse array of nutrients. Exposure to extremely cold stress during production can result in a more frequent occurrence of purple discoloration in cauliflower curds. In response to cold stress, plants naturally produce anthocyanins to eliminate reactive oxygen species (ROS) generated as a defense mechanism.MethodsThis research involved conducting mRNA sequencing analysis on cauliflower curds both before and after exposure to cold stress treatment.ResultsIt was determined that the up-regulation of anthocyanin biosynthesis-related genes CHS, CHI, DFR, ANS, UGFT, PAP1/2, and MYBL2 occurred significantly in response to cold stress, resulting in a significant increase in total anthocyanin content. Subsequently, miRNA sequencing was employed to identify miRNAs in cauliflower curds, followed by differential expression analysis. The results showed that Bna-miR289 and Ath-miR157a may play a key role in regulating the accumulation of anthocyanin in cauliflower curds. Furthermore, we utilized degradome sequencing data to predict the target genes of the identified miRNAs, resulting in the identification of BolK_3g48940.1, BolK_9g11680.1, BolK_7g41780.1, BolK_3g68050.1, and BolK_3g729700.1 as targets. Subsequently, the expression patterns of the miRNAs and their target genes were validated using qRT-PCR, the results showed that Ath-miR157a and its target genes BolK_3g68050.1 and BolK_3g72970.1 may be the key to the purple of cauliflower curds under cold stress. DiscussionOur preliminary findings identified key miRNAs and their target genes that may be involved in regulating anthocyanin synthesis, thereby enhancing the cold tolerance of cauliflower through mRNA, miRNA, and degradome sequencing. Overall, our study sheds light on the activation of anthocyanin synthesis in flower curds under cold stress conditions as a mechanism to enhance resilience to adverse environmental conditions.

Taste triggers a homeostatic temperature control in hungry flies.

Hungry animals consistently show a desire to obtain food. Even a brief sensory detection of food can trigger bursts of physiological and behavioral changes. However, the underlying mechanisms by which the sensation of food triggers the acute behavioral response remain elusive. We have previously shown in Drosophila that hunger drives a preference for low temperature. Because Drosophila is a small ectotherm, a preference for low temperature implies a low body temperature and a low metabolic rate. Here, we show that taste-sensing triggers a switch from a low to a high temperature preference in hungry flies. We show that taste stimulation by artificial sweeteners or optogenetics triggers an acute warm preference, but is not sufficient to reach the fed state. Instead, nutrient intake is required to reach the fed state. The data suggest that starvation recovery is controlled by two components: taste-evoked and nutrient-induced warm preferences, and that taste and nutrient quality play distinct roles in starvation recovery. Animals are motivated to eat based on time of day or hunger. We found that clock genes and hunger signals profoundly control the taste-evoked warm preferences. Thus, our data suggest that the taste-evoked response is one of the critical layers of regulatory mechanisms representing internal energy homeostasis and metabolism.

Taste triggers a homeostatic temperature control in hungry flies

Hungry animals consistently show a desire to obtain food. Even a brief sensory detection of food can trigger bursts of physiological and behavioral changes. However, the underlying mechanisms by which the sensation of food triggers the acute behavioral response remain elusive. We have previously shown in Drosophila that hunger drives a preference for low temperature. Because Drosophila is a small ectotherm, a preference for low temperature implies a low body temperature and a low metabolic rate. Here, we show that taste-sensing triggers a switch from a low to a high temperature preference in hungry flies. We show that taste stimulation by artificial sweeteners or optogenetics triggers an acute warm preference, but is not sufficient to reach the fed state. Instead, nutrient intake is required to reach the fed state. The data suggest that starvation recovery is controlled by two components: taste-evoked and nutrient-induced warm preferences, and that taste and nutrient quality play distinct roles in starvation recovery. Animals are motivated to eat based on time of day or hunger. We found that clock genes and hunger signals profoundly control the taste-evoked warm preferences. Thus, our data suggest that the taste-evoked response is one of the critical layers of regulatory mechanisms representing internal energy homeostasis and metabolism.

Blocking adipocyte YY1 decouples thermogenesis from beneficial metabolism by promoting spermidine production.

The accumulation of mitochondria in thermogenic adipose tissue (i.e., brown and beige fat) increases energy expenditure, which can aid in alleviating obesity and metabolic disorders. However, recent studies have shown that knocking out key proteins required to maintain mitochondrial function inhibits the energy expenditure in thermogenic fat, and yet the knockout mice are unexpectedly protected from developing obesity or metabolic disorders when fed a high-fat diet (HFD). In the present study, non-biased sequencing-based screening revealed the importance of YY1 in the transcription of electron transport chain genes and the enhancement of mitochondrial function in thermogenic adipose tissue. Specifically, adipocyte YY1 null (YAKO) mice showed lower energy expenditure and were intolerant to cold stress. Interestingly, YAKO mice showed alleviation of HFD-induced metabolic disorders, which can be attributed to a suppression of adipose tissue inflammation. Metabolomic analysis revealed that blocking YY1 directed glucose metabolism toward lactate, enhanced the uptake of glutamine, and promoted the production of anti-inflammatory spermidine. Conversely, blocking spermidine production in YAKO mice reversed their resistance to HFD-induced disorders. Thus, although blocking adipocyte YY1 impairs the thermogenesis, it promotes spermidine production and alleviates adipose tissue inflammation, therefore leads to an uncoupling of adipose tissue energy expenditure from HFD-induced metabolic disorders.

Effects of low temperature stress on cold-resistant substances and gene expression in Spodoptera frugiperda (Lepidoptera: Noctuidae)

The fall armyworm Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is a major agricultural pest. Low temperature is an important factor that limits S. frugiperda survival and reproduction. The physiological cold tolerance indexes of S. frugiperda larvae from October 2022 to February 2023 were investigated. The results showed that the cold-resistant substances in S. frugiperda differed significantly among different months. The water content was the lowest in January. Lipids were the highest in December and January, trehalose and protein contents were the highest in December, and glycerol content was the highest in January. The contents of lipid, protein, trehalose, and glycerol were the highest in the 6th instar larvae, whereas the water content did not differ among the larva stages. The functions of two genes, including endothelial lipase (Eol1) and gastric lipase (Epl1) that were extracted from the transcriptome analysis of S. frugiperda in the cold resistance were assessed. After 24 h of cold stress, the mRNA levels of Eol1 and Epl1 RNA interference were significantly down-regulated by 60.76% and 82.53%, and the survival rate of S. frugiperda larvae decreased. Additionally, Eol1 and Epl1 silencing significantly decreased the lipid content and pupal weight of S. frugiperda. The results indicate that S. frugiperda larvae can change the contents in winter to response the cold conditions and the lipids plays an important role in the cold resistance of S. frugiperda.

Effects of chronic cold stress and thermal stress on growth performance, hepatic apoptosis, oxidative stress, immune response and gut microbiota of juvenile hybrid sturgeon (Acipenser baerii ♀ × A. schrenkii ♂)

The current study was conducted to investigate the effects of chronic cold stress and thermal stress on the growth performance, hepatic oxidative status, immune response, apoptosis and gut microbiota in juvenile hybrid sturgeon. The fish (initial mean weight: 21.4 ± 0.3 g) was reared at three temperatures (14 °C, 22 °C, and 30 °C) for 16 d, which were termed as low temperature group (LT), moderate temperature group (MT), and high temperature group (HT), respectively, and the second group was regarded as control group in this study. Each group was assigned randomly to three tanks with 15 fish per replica. The results indicated that cold stress resulted in a significant reduction of growth metrics and a significant increase of feed conversion ratio in fish compared with MT group. Interestingly, cold stress increased hepatocyte apoptosis revealed by TUNEL staining, along with nuclear disappearance in H&E-stained sections and elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Transcriptional levels of apoptosis-related genes and toll-like receptor signaling pathway components were significantly up-regulated in liver under cold stress. Compared with control group, in terms of thermal stress, the growth performance and feed utilization of fish were declined to some extent compared with MT group. Moreover, high temperature significantly elevated hepatic productions of malondialdehyde and hydrogen peroxide, as well as increased activities of some antioxidant enzymes in liver. In addition, low and high temperature induce changes in the composition of gut microbiota. Overall, the results suggested that cold stress decelerated growth performance, induced hepatocyte apoptosis, and enhanced innate immunity in hybrid sturgeon to cope with additional stressors. Whereas, thermal stress resulted in hepatic oxidative stress in liver and the protective responses in the antioxidant enzymes in fish were activated. These results provided insights into the different physiological adaptation strategies in responsive to cold stress and thermal stress in this cold-water fish.

Hypothermia on Admission Predicts Poor Outcomes in Adult Trauma Patients

BackgroundHypothermia is known to contribute to poor outcomes in trauma patients during acute phases. The aim of our study is to evaluate the effect of hypothermia on admission, upon in-hospital complications and mortality in adult trauma patients. MethodsWe performed a 5-year analysis of ACS-TQIP database (2017-2021). Patients with incomplete data, burns, inter-facility transfers, or documented as dead on arrival were excluded. Hypothermia (HT) was defined as a temperature of <35 degrees Celsius(°C), and Normothermia (NT) as ≥35°C to≤40°C measured at the time of patient arrival. Data were collected including demographic variables, mechanism of injury, injury severity, injury patterns, and shock index. Outcome variables were mortality, ICU length of stay (LOS), duration of mechanical ventilation, hospital LOS, and in-hospital complications. Multivariable regression analysis was performed. ResultsA total of 3,043,030 patients were included and 1% were hypothermic. HT patients were severely injured, developed in-hospital complications (17.1%vs.4.5%), had longer ICU LOS (4 (2-9) vs. 3 (2-5) days), hospital LOS (5 (2-12) vs. 4 (2-6) days), and higher mortality (23.4% vs. 2.3%). Hypothermia was independently associated with higher odds of mortality (OR:1.934 [1.858–2.013]). Subgroup analysis of patients with isolated traumatic brain injury revealed pre-hospital hypothermia to still be an independent predictor of mortality (OR: 1.728[1.600–1.867]). HT who underwent rewarming had a lower mortality, shorter hospital and ICU LOS. ConclusionPre-hospital hypothermia is independently associated with higher resource utilization, in-hospital complications, and mortality. Even in patients with isolated TBI, pre-hospital hypothermia increases the odds of mortality. Rewarming interventions can potentially improve outcomes among patients, even with mild hypothermia.

Genome-wide identification and expression analysis of the GT8 gene family in tomato(Solanum lycopersicum) and the functional of SlGolS1 under cold stress

Glycosyltransferases (GTs) are a diverse superfamily of enzymes involved in glycosylation reactions, with the GT8 (glycosyltransferase 8) playing a crucial role in plant growth, development, and abiotic stress responses. Tomato, widely cultivated and is a thermophilic plant. So it is significant to study how GT8 regulates cold resistance in tomato for plant growth. In this study, we screened the whole genome of tomato by using bioinformatics methods and identified 40 members of the GT8 gene family. Analysis of cold stress transcriptome data and qRT-PCR experiments revealed the potential significance of SlGolS1 in responding to cold stress. SlGolS1 was highly expressed in the stems and flowers of tomato, with its mature protein localized in the chloroplast. Used the VIGS method to transiently silence the SlGolS1 gene, the SlGolS1-silenced plants (pTRV2-SlGolS1) rendered tomato more sensitive to cold stress compared with the control (pTRV2) tomato plant phenotype after cold treatment; enzyme activity assays showed that oxidative damage was more severe in the pTRV2-SlGolS1. In summary, SlGolS1 positively regulates cold resistance in tomato.

Influence of synthetic neuropeptide of opioid action on functions of 3D cultures in cold stress

influence of synthetic neuropeptide of opioid action on functions of 3D cultures in cold stress

Structural insights to the RRM-domain of the glycine-rich RNA-binding protein from Sorghum bicolor and its role in cold stress tolerance in E. coli

Sorghum bicolor Glycine-rich RNA-binding protein (SbGRBP), exhibit the ability to bind both single-stranded and double-stranded DNA. The expression of SbGRBP is regulated by heat stress, with the protein localizing to the nucleus and cytosol. The present study delves into the structure and ssDNA binding ability of its truncated version (SbGRBP1–119) which lacks glycine rich domain (GR). This protein has the ability to bind ssDNA Using Nuclear Magnetic Resonance (NMR) spectroscopy, we have revealed the secondary structure of SbGRBP1–119, highlighting the typical configuration of GRBPs with four β-sheets and two α-helices. Notably, we found two additional α-helices at the N-terminal region that seem to interact with ssDNA, a novel observation for GRBPs. Key residues crucial for ssDNA binding were identified, suggesting a specific interaction with the oligonucleotide sequence 5’-TTCTGG-3′. Preliminary assays hinted that SbGRBP1–119 might bolster E. coli resilience to cold stress, indicating a potential chaperone-like role under stress conditions. This study sheds light on the structural basis of SbGRBP1–119's interaction with nucleic acids, deepening our understanding about the role of GRBPs' in RNA metabolism and regulation.

Observed determinants of urban outdoor thermal exposure during hot summer and snowy winter periods in a humid continental climate

Many cities in the midlatitudes experience both extreme heat and cold, and pedestrians are exposed to thermal extremes that cause bodily stress. With growing urban populations, city design that contributes to mitigating summer heat while reducing winter cold exposure is increasingly important. Pedestrian thermal exposure depends on several microclimatic factors, including shortwave and longwave radiation absorption, which can be quantified by the mean radiant temperature (Tmrt). Limited research has been conducted on the radiative components of thermal exposure in hot, humid summers and cold, snowy winters. We gathered micrometeorological data from diverse urban sites and in multiple seasons in Guelph, Canada, using a mobile human-biometeorological weather station (MaRTy cart) that applies the six-directional method to determine Tmrt. Seasonal datasets were analysed and compared to examine the drivers of thermal exposure and recommend strategies for mitigating heat and cold stress. In summer, shade is the primary factor that reduces daytime heat exposure and it slightly increases nighttime heat exposure. Enhanced pervious ground cover is a secondary factor day and night. In winter, reduced shade alleviated daytime cold exposure, while snow cover provided daytime benefits from increased solar reflections and post-sunset penalties associated with reduced longwave radiation from low snow surface temperatures.

Evolution of thaumatin-like proteins in rosaceae and rapid response to cold stimulation coordinated with PmEOBⅡ in the floral scent formation process of Prunus mume

Prunus mume has a long history of cultivation in China as the ornamental plant. It has been observed for a long time that the colder weather the weather appear, the sweeter the flowers produce, coldness stress may contribute to the formation of its floral scents. Here, in previous transcription matrix during scent formation period, we recognized thaumatin-like proteins from the core co-expression members. Thus, we performed the identification of thaumatin-like proteins in the Rosaceae genomes, characterized by conserved cysteine residues and tag sequences to explain the relationship between abiotic stress and floral metabolism. The numbers of TLPs ranged from 22 to 34. Most of the TLP members in Group 9 displayed congregated and expanded. A total of seven tandem duplication events occurred in 27 PmTLPs, which could be the primary driving force behind PmTLP gene expansion. The promoters of the PmTLPs contained various types of cis-elements. Additionally, there existed several miRNAs for certain PmTLPs. As a result, PmTLPs displayed tissue-specific expression trends, and expressions varied across different developmental stages of flowers. For highly activated members, PmTLP19 and 23 increased sharply after 4 h under chilling induction compared with a slow increase by ABA treatment. PmTLPs, PmEOBII, and PmMYB4 owned a positive expression correlation in both responces. Finally, the yeast two-hybrid results also indicated a strong interaction between PmEOBII and PmTLP19. Our results establish the foundation for a comprehensive investigation into the molecular mechanism of PmTLPs involved in the cold-resistant defense response of Prunus mume. Additionally, it will facilitate the identification of genes associated with regulating floral compounds in P. mume.

GhBZR15 improved the tolerance of cotton to cold and salt stress revealed by genome-wide characterization of BZR genes family

Brassinazole resistant (BZR) transcription factors play important roles in brassinosteroids (BRs) signaling pathway of plants, which are involved in many developmental processes and the responses to abiotic stress by regulating the expression of related genes. In order to explore the molecular mechanism of BZR transcription factors in cotton in response to abiotic stress, the BZR transcription factors in four cotton genomes were identified and analyzed. A total of 67 BZR transcription factors were identified and divided into three subfamilies according to their genetic relationship. The expression levels of BZR under cold, heat, salt, and drought treatments were analyzed to predict their function under abiotic stress. Promoter analysis of BZR proteins showed that light signaling can enhance the BZR transcriptional activity. The subcellular localization experiment showed that GhBZR15 protein was mainly distributed in the nucleus. Arabidopsis thaliana L. overexpressing GhBZR15 gene showed stronger cold tolerance and salt tolerance than wild type. These results, combined with the GhBZR protein-interaction network, suggest that the interaction of GhBZR with phytochrome interacting factors (PIF4) plays an important role in abiotic stress responses. These findings provide a basis for further understanding the function of BZR in cotton.

Targeted delivery of a selenium-sulfa compound via cationic starch microparticles: Modulation of oxidative stress and pain pathways in fibromyalgia-like symptoms in mice

Cationic starch microparticles (CStMPs) loaded with 4-amino-3 -(phenylselenyl)benzenesulfonamide (4-APSB) were prepared and investigated in a model of fibromyalgia (FM) induced by intermittent cold stress (ICS) in male and female Swiss mice. The CStMPs/4-APSB were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, zeta potential, and particle size measurements, providing information about their chemical composition, surface charge, morphology/microstructure, and size (1.50 ± 0.5 μm). Following ICS exposure, the animals were treated with free 4-APSB (1 mg/kg), CStMPs/4-APSB (containing 0.13 mg of 4-APSB per mg of microparticles), or CStMPs, from days 5 to 10. The results revealed the successful incorporation of 4-APBS in the CStMPs. Free 4-APSB and CStMPs/4-APSB reversed nociceptive- and depressive-related behaviors in male and female mice exposed to ICS, attenuating the hallmark symptoms of FM. Those treatments (free 4-APSB and CStMPs/4-APSB) normalized the monoamine oxidase (MAO)-A activity in the cerebral cortex and the oxidative damage, providing the correct functioning of the enzyme Ca2+ -ATPase in the cerebral cortex and hippocampus of mice exposed to ICS. The CStMPs/4-APSB modulated the oxidative stress markers, specifically in the spinal cord of mice - an anatomical region intricately linked to pain pathways.

The Role of Rootstock Selection in Pistachio Cultivation

Rootstocks are critical in selecting pistachio (Pistacia vera L.) cultivation and its impact on scion performance. Pistachio rootstocks exhibited distinct absorption capabilities, impacting leaf nutrient concentrations and tree health. The review discusses current knowledge on the influence of various rootstocks on growth habit, nutrient uptake, yield, nut quality, alternate bearing, and responses to abiotic stresses such as salinity, drought, and cold. Contrary to the traditional belief linking higher yield solely to vigor and size, the review emphasized the need for an in-depth understanding of the interplay between rootstock, scion, and their interaction to optimize yield. Additionally, we discussed the influence of rootstock selection on pistachio nut quality, including early splitting, hull cracking, and fatty acid composition. It addressed the complex phenomenon of alternate bearing, highlighting how vigorous rootstocks could affect cyclic variations in crop yield through increased carbohydrate resources. Rootstocks mitigate salinity stress, enhancing drought tolerance and preserving nut quality under water stress. The study emphasized the significance of rootstock choice in cold climates, advocating for identifying and using cold-tolerant rootstocks to enhance orchard resilience against cold stress. The findings provide valuable insights for growers and researchers, facilitating informed decision-making regarding rootstock selection in pistachio cultivation worldwide.

Stressdrives premature hive exiting behavior that leads to death in young honey bee (Apis mellifera) workers.

The Western honey bee, Apis mellifera, is an economically important pollinator, as well as a tractable species for studying the behavioral intricacies of eusociality. Honey bees are currently being challenged by multiple biotic and environmental stressors, many of which act concomitantly to affect colony health and productivity. For instance, developmental stress can lead workers to become precocious foragers and to leave the hive prematurely. Precocious foragers have decreased flight time and lower foraging efficiency, which can ultimately lower colony productivity and even lead to colony collapse. In this study, we tested the hypothesis that stress during pupal development can cause young workers to exit the hive prematurely before they are physically able to fly. This premature exiting behavior results in death outside the hive soon thereafter. To determine how various stressors may lead bees to perform this behavior, we subjected workers during the last pupal stage to either cold stress (26°C for 24h), heat stress (39°C for 24h), or Varroa destructor mite parasitization, and compared the rate of premature hive exits between stressed bees and their respective control counterparts. Upon emergence, we individually tagged focal bees in all treatment groups and introduced them to a common observation hive. We then followed tagged bees over time and monitored their survivorship, as well as their likelihood of performing the premature hive exiting behavior. We also dissected the hypopharyngeal glands of all treatment and control bees sampled. We found that significantly more bees in all three treatment groups exited the hive prematurely compared to their control counterparts. Bees in all treatment groups also had significantly smaller hypopharyngeal glands than control bees. Our results suggest that premature hive exiting behavior is driven by stress and is potentially a form of accelerated age polyethism that leads to premature death.

In silico analysis of L- and G-type lectin receptor kinases in tomato: evolution, diversity, and abiotic responses

Solanum lycopersicum (family: Solanaceae) is a crucial crop and model organism for many phenotypic traits, and its sequenced genome provides valuable insights into plant biology and crop improvement. This study investigated lectin receptor-like kinases (LecRLKs) in tomato, focusing on L-type and G-type families. Mining the tomato genome (ITAG2.4) revealed 161 putative lectin genes across seven families, with GNA-related genes being the most abundant. Gene duplication analysis indicated that tandem and segmental duplications were the primary mechanisms driving LecRLK gene family expansion, particularly for G-type LecRLKs. These duplicated genes showed evidence of both purifying and negative selection, suggesting functional conservation and sub-functionalization. L-type and G-type LecRLKs exhibited diverse domain rearrangement architectures and subcellular localizations, with G-type LecRLKs showing greater expansion and architectural diversity. Differential expression analysis during abiotic stress (drought, heat, and cold stress) revealed key responsive genes. During drought stress, 63.2% of L-type and 18.5% of G-type LecRLK genes were expressed, with L-type Solyc09g005000.1 and G-type Solyc03g078360.1 genes showing significant 2-fold upregulation. Heat stress (42 °C) induced the upregulation of L-type Solyc04g071000.1 and G-type Solyc03g078360.1 and Solyc04g008400.1, particularly after 12–24 h of exposure. Promoter analysis revealed numerous stress-related cis-elements. Transcription factor predictions and miRNA targeting sites suggest complex regulatory mechanisms. This comprehensive in silico characterization of tomato LecRLKs, including their expansion patterns and evolutionary pressures, provides insights into their potential roles in abiotic stress responses and lays the groundwork for enhancing crop resilience through targeted breeding or genetic engineering approaches.

NtSAP9 confers freezing tolerance in Nicotiana tabacum plants

Abiotic stresses, such as extreme temperatures, drought, and salinity, significantly affect plant growth and productivity. Among these, cold stress is particularly detrimental, impairing cellular processes and leading to reduced crop yields. In recent years, stress-associated proteins (SAPs) containing A20 and AN1 zinc-finger domains have emerged as crucial regulators in plant stress responses. However, the functions of SAPs in tobacco plants remain unclear. Here, we isolated Nicotiana tabacum SAP9 (NtSAP9), whose expression was induced by cold treatment, based on RNA-sequences data. Knock down of NtSAP9 expression reduced freezing tolerance, while overexpression conferred freezing tolerance in transgenic tobacco plants, as indicated by relative electrolytic leakage and photosystem II photochemical efficiency. Untargeted metabolomics via liquid chromatography-tandem mass spectrometry revealed distinct metabolic profiles between WT and NtSAP9-overexpressing tobacco plants under normal and low temperature conditions. Upregulation of amino acids like D-Glutamine, DL-Glutamine, and O-Acetyl-L-serine suggests NtSAP9 enhances cold tolerance. Further expression analysis by quantitative real-time PCR indicated that NtSAP9 participates in cold stress response possibly through amino acid synthesis-related genes expression, such as glutamine synthetase and glutamate dehydrogenase. These findings improve our understanding of SAP proteins in tobacco's response to cold stress.

ERD14 regulation by the HY5- or HY5-MED2 module mediates the cold signal transduction of asparagus bean.

Cold stress affects the growth, development, and yield of asparagus bean (Vigna unguiculata subsp. sesquipedalis). Mediator (MED) complex subunits regulate the cold tolerance of asparagus bean, but the underlying regulatory mechanisms remain unclear. Here, VunMED2 positively responds to cold stress of asparagus beans. Under cold acclimation and freezing treatment, the survival rate, ROS scavenging activity, and expression levels of VunMED2 were increased in VunMED2 transgenic plants. Natural variation in the promoter of VunMED2 in two different cold-tolerant asparagus beans was observed. Under cold stress, the expression of the GUS reporter gene was higher in cold-tolerant plants than in cold-sensitive plants, and the expression of the GUS reporter gene was tissue-specific. VunHY5 positively influenced the expression of VunMED2 by binding to the E-box motif, and the transcriptional activation of the promoter was stronger in the cold-tolerant variety than in cold-sensitive plants. VunHY5 overexpression improved plant freezing resistance by increasing the antioxidant capacity and expression of dehydrin genes. VunHY5 and VunMED2 play a synergistic role in binding to the G-box/ABRE motif and transcriptionally activating the expression of VunERD14. VunERD14 complemented the med2 mutant, which could positively respond to plant freezing resistance by reducing membrane lipid peroxidation and improving the antioxidant capacity. Therefore, the VunHY5-VunERD14 module and the VunHY5-VunMED2-VunERD14 positive cascade effect are involved in the cold signal transduction in asparagus bean. Our findings have implications for the breeding of asparagus bean varieties with improved cold tolerance.

Comparison of Gut Microbiota in Overwintering Bees: Apis cerana vs. Apis mellifera

Bees play important roles in socio-economic development, biodiversity conservation, and ecosystem stability. However, during the cold season, resources become limited, leading to significant losses in bee colonies. Although many studies have described the characteristics of winter bees and demonstrated that notable changes occur in their gut microflora, the underlying mechanisms remain yet to be fully elucidated. Therefore, this study was conducted to compare the gut microbiota dynamics of overwintering bees. Sample acquisition involved randomly selecting ten colonies each from three bee farms containing Apis cerana (AC) and Apis mellifera (AM), followed by dissection for further analysis. DNA was extracted, and 16S rDNA sequencing, along with various bioinformatics tools, was used to assess microbial diversity, functional differences, and species comparisons between AC and AM gut microbiota. AC exhibited lower β diversity in the gut microbiota than AM during winter. Moreover, Gilliamella and Apibacter were relatively more abundant in AC. Regarding microbial functions, key pathways included the phosphotransferase system, galactose metabolism, the pentose phosphate pathway, and carbohydrate transport and metabolism. These results suggest the presence of microbial diversity differences between AC and AM, with the differential microbial functions mainly enriched in metabolic pathways that facilitate adaptation to cold environmental stress.