Expression Of Stress-responsive Genes Research Articles

ZmNHL2 enhances drought tolerance by regulating the expression of stress-responsive genes and ABA signaling pathway in maize

ZmNHL2 enhances drought tolerance by regulating the expression of stress-responsive genes and ABA signaling pathway in maize

Neuromolecular mechanisms related to reflex behaviour in Aplysia are affected by ocean acidification

While ocean acidification (OA) impacts the behaviour of marine organisms, the complexity of neurosystems makes linking behavioural impairments to environmental change difficult. Using a simple model, we exposed Aplysia to ambient or elevated CO 2 conditions (approx. 1500 µatm) and tested how OA affected the neuromolecular response of the pleural–pedal ganglia and caused tail withdrawal reflex (TWR) impairment. Under OA, Aplysia relax their tails faster with increased sensorin-A expression, an inhibitor of mechanosensory neurons. We further investigate how OA affects habituation training output, which produced a ‘sensitization-like’ behaviour and affected vesicle transport and stress response gene expression, revealing an influence of OA on learning. Finally, gabazine did not restore normal behaviour and elicited little molecular response with OA, instead, vesicular transport and cellular signalling link other neurotransmitter processes with TWR impairment. Our study shows the effects of OA on neurological tissue parts that control for behaviour.

Expression of mitochondrial oxidative stress response genes in muscle is associated with mitochondrial respiration, physical performance, and muscle mass in the Study of Muscle, Mobility, and Aging.

Gene expression in skeletal muscle of older individuals may reflect compensatory adaptations in response to oxidative damage that preserve tissue integrity and maintain function. Identifying associations between oxidative stress response gene expression patterns and mitochondrial function, physical performance, and muscle mass in older individuals would further our knowledge of mechanisms related to managing molecular damage that may be targeted to preserve physical resilience. To characterize expression patterns of genes responsible for the oxidative stress response, RNA was extracted and sequenced from skeletal muscle biopsies collected from 575 participants (≥70 years old) from the Study of Muscle, Mobility, and Aging. Expression levels of 21 protein-coding RNAs related to the oxidative stress response were analyzed in relation to six phenotypic measures, including maximal mitochondrial respiration from muscle biopsies (Max OXPHOS), physical performance (VO2 peak, 400-m walking speed, and leg strength), and muscle size (thigh muscle volume and whole-body D3Cr muscle mass). The mRNA level of the oxidative stress response genes most consistently associated across outcomes are preferentially expressed within the mitochondria. Higher expression of mRNAs that encode generally mitochondria located proteins SOD2, TRX2, PRX3, PRX5, and GRX2 were associated with higher levels of mitochondrial respiration and VO2 peak. In addition, greater SOD2, PRX3, and GRX2 expression was associated with higher physical performance and muscle size. Identifying specific mechanisms associated with high functioning across multiple performance and physical domains may lead to targeted antioxidant interventions with greater impacts on mobility and independence.

StMAPKK5 responds to heat stress by regulating potato growth, photosynthesis, and antioxidant defenses.

As a conserved signaling pathway, mitogen-activated protein kinase (MAPK) cascade regulates cellular signaling in response to abiotic stress. High temperature may contribute to a significant decrease in economic yield. However, research into the expression patterns of StMAPKK family genes under high temperature is limited and lacks experimental validation regarding their role in supporting potato plant growth. To trigger heat stress responses, potato plants were grown at 35°C. qRT-PCR was conducted to analyze the expression pattern of StMAPKK family genes in potato plants. Plant with StMAPKK5 loss-of-function and gain-of-function were developed. Potato growth and morphological features were assessed through measures of plant height, dry weight, and fresh weight. The antioxidant ability of StMAPKK5 was indicated by antioxidant enzyme activity and H2O2 content. Cell membrane integrity and permeability were suggested by relative electrical conductivity (REC), and contents of MDA and proline. Photosynthetic capacity was next determined. Further, mRNA expression of heat stress-responsive genes and antioxidant enzyme genes was examined. In reaction to heat stress, the expression profiles of StMAPKK family genes were changed. The StMAPKK5 protein is located to the nucleus, cytoplasm and cytomembrane, playing a role in controlling the height and weight of potato plants under heat stress conditions. StMAPKK5 over-expression promoted photosynthesis and maintained cell membrane integrity, while inhibited transpiration and stomatal conductance under heat stress. Overexpression of StMAPKK5 triggered biochemical defenses in potato plant against heat stress, modulating the levels of H2O2, MDA and proline, as well as the antioxidant activities of CAT, SOD and POD. Overexpression of StMAPKK5 elicited genetic responses in potato plants to heat stress, affecting heat stress-responsive genes and genes encoding antioxidant enzymes. StMAPKK5 can improve the resilience of potato plants to heat stress-induced damage, offering a promising approach for engineering potatoes with enhanced adaptability to challenging heat stress conditions.

Overexpression of NB-LRR Gene AtRPM1(D505V) Improved Drought and Salt Resistance and Decreased Cold Tolerance in Transgenic Rice

Abiotic stimuli severely restrict the growth and development of plants, resulting in massive losses in the quality and yield of crops. Exploring genes that can improve crop tolerance to abiotic stress is important. In a previous study, we found that overexpression of the Arabidopsis nucleotide-binding domain leucine-rich repeat (NB-LRR) gene AtRPM1(D505V) increased disease resistance in rice. In this research, we found that AtRPM1(D505V) transgenic plants were more sensitive to abscisic acid (ABA) than wild type (WT) plants. Abiotic-stress resistance in AtRPM1(D505V) transgenic plants was investigated. We found that AtRPM1(D505V) transgenic plants exhibited improved resistance to drought and salt stress; the phonotype and survival rates of transgenic rice were better than WT plants. The expression of stress responsive genes including OsDREB2A, OsDREB2B, OsRD22, and OsRD29A were significantly upregulated in AtRPM1(D505V) overexpressed plants than in WT plants. Moreover, the activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) were significantly increased in AtRPM1(D505V) overexpressed plants than in WT plants under drought and salt stress. Under cold stress, the expression of stress responsive genes and the activities of antioxidant enzymes in AtRPM1(D505V) transgenic plants were significantly lower than in WT plants. Our research demonstrated that AtRPM1(D505V) confers drought and salt resistance to transgenic rice. Therefore, AtRPM1(D505V) could act as a potential candidate gene to cultivate drought- and salt-tolerant plants.

Azolla filiculoides extract improved salt tolerance in wheat (Triticum aestivum L.) is associated with prompting osmostasis, antioxidant potential and stress-interrelated genes

The growth and productivity of crop plants are negatively affected by salinity-induced ionic and oxidative stresses. This study aimed to provide insight into the interaction of NaCl-induced salinity with Azolla aqueous extract (AAE) regarding growth, antioxidant balance, and stress-responsive genes expression in wheat seedlings. In a pot experiment, wheat kernels were primed for 21 h with either deionized water or 0.1% AAE. Water-primed seedlings received either tap water, 250 mM NaCl, AAE spray, or AAE spray + NaCl. The AAE-primed seedlings received either tap water or 250 mM NaCl. Salinity lowered growth rate, chlorophyll level, and protein and amino acids pool. However, carotenoids, stress indicators (EL, MDA, and H2O2), osmomodulators (sugars, and proline), antioxidant enzymes (CAT, POD, APX, and PPO), and the expression of some stress-responsive genes (POD, PPO and PAL, PCS, and TLP) were significantly increased. However, administering AAE contributed to increased growth, balanced leaf pigments and assimilation efficacy, diminished stress indicators, rebalanced osmomodulators and antioxidant enzymes, and down-regulation of stress-induced genes in NaCl-stressed plants, with priming surpassing spray in most cases. In conclusion, AAE can be used as a green approach for sustaining regular growth and metabolism and remodelling the physio-chemical status of wheat seedlings thriving in salt-affected soils.

Genome-wide identification of the plant homeodomain-finger family in rye and ScPHD5 functions in cold tolerance and flowering time.

111 PHD genes were newly identified in rye genome and ScPHD5's role in regulating cold tolerance and flowering time was suggested. Plant homeodomain (PHD)-finger proteins regulate the physical properties of chromatin and control plant development and stress tolerance. Although rye (Secale cereale L.) is a major winter crop, PHD-finger proteins in rye have not been studied. Here, we identified 111 PHD genes in the rye genome that exhibited diverse gene and protein sequence structures. Phylogenetic tree analysis revealed that PHDs were genetically close in monocots and diverged from those in dicots. Duplication and synteny analyses demonstrated that ScPHDs have undergone several duplications during evolution and that high synteny is conserved among the Triticeae species. Tissue-specific and abiotic stress-responsive gene expression analyses indicated that ScPHDs were highly expressed in spikelets and developing seeds and were responsive to cold and drought stress. One of these genes, ScPHD5, was selected for further functional characterization. ScPHD5 was highly expressed in the spike tissues and was localized in the nuclei of rye protoplasts and tobacco leaves. ScPHD5-overexpressing Brachypodium was more tolerant to freezing stress than wild-type (WT), with increased CBF and COR gene expression. Additionally, these transgenic plants displayed an extremely early flowering phenotype that flowered more than two weeks earlier than the WT, and vernalization genes, rather than photoperiod genes, were increased in the WT. RNA-seq analysis revealed that diverse stress response genes, including HSPs, HSFs, LEAs, and MADS-box genes, were also upregulated in transgenic plants. Our study will help elucidate the roles of PHD genes in plant development and abiotic stress tolerance in rye.

Oceanobacillus picturae alleviates cadmium stress and promotes growth in soybean seedlings

Cadmium (Cd) is a heavy metal that significantly impacts human health and the environment. Microorganisms play a crucial role in reducing heavy metal stress in plants; however, the mechanisms by which microorganisms enhance plant tolerance to Cd stress and the interplay between plants and microorganisms under such stress remain unclear. In this study, Oceanobacillus picturae (O. picturae) was isolated for interaction with soybean seedlings under Cd stress. Results indicated that Cd treatment alone markedly inhibited soybean seedling growth. Conversely, inoculation with O. picturae significantly improved growth indices such as plant height, root length, and fresh weight, while also promoting recovery in soil physiological indicators and pH. Metabolomic and transcriptomic analyses identified 157 genes related to aspartic acid, cysteine, and flavonoid biosynthesis pathways. Sixty-three microbial species were significantly associated with metabolites in these pathways, including pathogenic, adversity-resistant, and bioconductive bacteria. This research experimentally demonstrates, for the first time, the growth-promoting effect of the O. picturae strain on soybean seedlings under non-stress conditions. It also highlights its role in enhancing root growth and reducing Cd accumulation in the roots under Cd stress. Additionally, through the utilization of untargeted metabolomics, metagenomics, and transcriptomics for a multi-omics analysis, we investigated the impact of O. picturae on the soil microbiome and its correlation with differential gene expression in plants. This innovative approach unveils the molecular mechanisms underlying O. picturae's promotion of root growth and adaptation to Cd stress.

A cyclic nucleotide-gated channel gene HcCNGC21 positively regulates salt and drought stress responses in kenaf (Hibiscus cannabinus L.)

Cyclic Nucleotide-Gated Channels (CNGCs) serve as Ca2+ permeable cation transport pathways, which are involved in the regulation of various biological functions such as plant cell ion selective permeability, growth and development, responses to biotic and abiotic stresses. At the present study, a total of 31 CNGC genes were identified and bioinformatically analyzed in kenaf. Among these genes, HcCNGC21 characterized to localize at the plasma membrane, with the highest expression levels in leaves, followed by roots. In addition, HcCNGC21 could be significantly induced under salt or drought stress. Virus-induced gene silencing (VIGS) of HcCNGC21 in kenaf caused notable growth inhibition under salt or drought stress, characterized by reductions in plant height, stem diameter, leaf area, root length, root surface area, and root tip number. Meanwhile, the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were significantly decreased, accompanied by reduced levels of osmoregulatory substances and total chlorophyll content. However, ROS accumulation and Na+ content increased. The expression of stress-responsive genes, such as HcSOD, HcPOD, HcCAT, HcERF3, HcNAC29, HcP5CS, HcLTP, and HcNCED, was significantly downregulated in these silenced lines. However, under salt or drought stress, the physiological performance and expression of stress-related genes in transgenic Arabidopsis thaliana plants overexpressing HcCNGC21 were diametrically opposite to those of TRV2-HcCNGC21 kenaf line. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays revealed that HcCNGC21 interacts with HcAnnexin D1. These findings collectively underscore the positive role of HcCNGC21 in plant resistance to salt and drought stress.

The IRE1α/XBP1 pathway sustains cytokine responses of group 3 innate lymphoid cells in inflammatory bowel disease.

Group 3 innate lymphoid cells (ILC3s) are key players in intestinal homeostasis. Endoplasmic reticulum (ER) stress is linked to inflammatory bowel disease (IBD). Herein, we used cell culture, mouse models, and human specimens to examine if ER stress in ILC3s impacts IBD pathophysiology. We show that mouse intestinal ILC3s exhibited a 24h-rhythmic expression pattern of the master ER stress response regulator, IRE1α/XBP1. Proinflammatory cytokine IL-23 selectively stimulated IRE1α/XBP1 in mouse ILC3s through mitochondrial reactive oxygen species (mtROS). IRE1α/XBP1 was activated in ILC3s of mice exposed to experimental colitis and in inflamed human IBD specimens. Mice with Ire1α deletion in ILC3s (Ire1αΔRorc) showed reduced expression of ER stress response and cytokine genes including Il22 in ILC3s and were highly vulnerable to infections and colitis. Administration of IL-22 counteracted their colitis susceptibility. In human ILC3s, IRE1 inhibitors suppressed cytokine production, which was upregulated by an IRE1 activator. Moreover, the frequencies of intestinal XBP1s+ ILC3s in Crohn's disease patients before administration of ustekinumab, an anti-IL-12/IL-23 antibody, positively correlated with response to treatment. We demonstrate that a non-canonical mtROS-IRE1α/XBP1 pathway augments cytokine production by ILC3s and identify XBP1s+ ILC3s as a potential biomarker for predicting response to anti-IL-23 therapies in IBD.

Overexpression of a pearl millet WRKY transcription factor gene, PgWRKY74, in Arabidopsis retards shoot growth under dehydration and salinity-stressed conditions.

Pearl millet (Cenchrus americanus) is a cereal crop that can tolerate high temperatures, drought, and low-fertility conditions where other crops lose productivity. However, genes regulating this ability are largely unknown. Transcription factors (TFs) regulate transcription of their target genes, regulate downstream biological processes, and thus are candidates for regulators of such tolerance of pearl millet. PgWRKY74 encodes a group IIc WRKY TF in pearl millet and is downregulated by drought. PgWRKY74 may have a role in drought tolerance. The objective of this study was to gain insights into the physiological and biochemical functions of PgWRKY74. Yeast one-hybrid and gel shift assays were performed to examine transcriptional activation potential and deoxyribonucleic acid (DNA)-binding ability, respectively. Transgenic Arabidopsis thaliana plants overexpressing PgWRKY74-green fluorescent protein (GFP) fusion gene were generated and tested for growth and stress-responsive gene expression under mannitol and NaCl-stressed conditions. A construct with PgWRKY74 enabled yeast reporter cells to survive on test media in the yeast one-hybrid assays. The electrophoretic mobility of DNA with putative WRKY TF-binding motifs was lower in the presence of a recombinant PgWRKY74 protein than its absence. The PgWRKY74-GFP-overexpressing Arabidopsis plants exhibited smaller rosette areas than did wild-type plants under mannitol-stressed and NaCl-stressed conditions, and exhibited weaker expression of RD29B, which is induced by the stress-related phytohormone abscisic acid (ABA), under the mannitol-stressed condition. PgWRKY74 have transcriptional activation potential and DNA-binding ability, and can negatively regulate plant responses to mannitol and NaCl stresses, possibly by decreasing ABA levels or ABA sensitivity.

Improved Waterlogging Tolerance in Roots of Cucumber Plants after Inoculation with Arbuscular Mycorrhizal Fungi

Mycorrhizal symbiosis enhances host plant resistance to various unfavorable environmental stresses, but whether and how it also enhances waterlogging tolerance in cucumber plants is not known. The objective of this study was to analyze the effect of Paraglomus occultum inoculation on biomass production, osmolyte levels, and the expression of 12 heat shock protein 70 (Hsp70) genes and 14 plasma membrane intrinsic protein (PIP) genes in the roots of cucumber plants under a short-term waterlogging stress (WS) (5 days) condition. Although the short-term WS treatment significantly inhibited the arbuscular mycorrhizal fungal colonization of roots, the inoculation with arbuscular mycorrhizal fungi (AMFs) significantly increased leaf, stem, and root biomass under WS. AMF inoculation also significantly increased root glucose, sucrose, betaine, and proline contents, along with decreased fructose levels, compared with the uninoculated control. More CsHsp70 and CsPIP genes were up-regulated in AMF-inoculated plants than in AMF-uninoculated plants in response to WS. AMF inoculation showed no significant effect on the expression of any of the examined CsHsp70 genes under no-waterlogging stress, but it did raise the expression of 11 of 12 CsHsp70 genes under WS. AMF colonization also down-regulated or had no effect on CsPIP expression under no-waterlogging stress, whereas it up-regulated the expression of 12 of the 14 CsPIP genes under WS. It is concluded that AMF inoculation enhances waterlogging tolerance in cucumber plants by increasing osmolyte levels and stress-responsive gene (CsPIP and CsHsp70) expression.

The UDP-glycosyltransferase OsUGT706D2 positively regulates cold and submergence stress tolerance in rice

In a genome-wide association study, we identified a rice UDP-glycosyltransferase gene, OsUGT706D2, whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid (ABA). OsUGT706D2 positively regulated the biosynthesis of tricin-4′-O-(syringyl alcohol) ether-7-O-glucoside at both the transcriptional and metabolic levels. OsUGT706D2 mediated cold and submergence tolerance by modulating the expression of stress-responsive genes as well as the abscisic acid (ABA) signaling pathway. Gain of function of OsUGT706D2 increased cold and submergence tolerance and loss of function of OsUGT706D2 reduced cold tolerance. ABA positively regulated OsUGT706D2-mediated cold tolerance but reduced submergence tolerance. These findings suggest the potential use of OsUGT706D2 for improving abiotic stress tolerance in rice.

Cell type-dependent modulation of senescence features using Weo electrolyzed water.

Electrolyzed-reduced water has powerful antioxidant properties with constituents that scavenge reactive oxygen species (ROS), which are known to be produced by several intrinsic and extrinsic processes. When there is an imbalance between ROS production and antioxidant defenses, oxidative stress occurs. Persistent oxidative stress leads to cellular senescence, an important hallmark of aging, and is involved in several age-related conditions and illnesses. This study aims to investigate whether Weo electrolyzed water (WEW) could modulate the phenotype of senescent cells. We compared normal human lung fibroblasts (BJ) and breast cancer cells (T47D) treated with hydrogen peroxide (H2O2) to induce senescence. We assessed the molecular impact of WEW on markers of cellular senescence, senescence-associated secretory phenotype (SASP) factors, and stress response genes. Treatment with WEW modulated markers of cellular senescence, such as the senescence-associated β-galactosidase (SA-β-gal) activity, EdU incorporation and p21 expression, similarly in both cell types. However, WEW modulated the expression of SASP factors and stress response genes in a cell type-dependent and opposite fashion, significantly decreasing them in BJ cells, while stimulating their expression in T47D cells. Reduction in the expression of SASP factors and stress-related genes in BJ cells suggests that WEW acts as a protective factor, thereby reducing oxidative stress in normal cells, while making cancer cells more sensitive to the effects of cellular stress, thus increasing their elimination and consequently reducing their deleterious effects. These findings suggest that, due to its differential effects as a senomorphic factor, WEW could have a positive impact on longevity and age-related diseases.

BrERF109 positively regulates the tolerances of drought and salt stress in Chinese cabbage

Ethylene response factors (ERFs) are plant-specific transcription factors and play essential roles in plants’ defense responses to abiotic stresses. In this study, we identified an ethylene response factor BrERF109, and explored its roles in response to drought and salt stress. The BrERF109 protein contained an AP2 domain and was localized in the nucleus. Expression analysis suggested that BrERF109 was mainly expressed in root and leaf, and highly induced by drought, salt, heat, and cold stresses. Ectopic expression of BrERF109 in Arabidopsis improved the tolerance to drought and salt stress in transgenic plants, accompanied by reduced ABA sensitivity, enhanced antioxidant enzyme activities and chlorophyll content, as well as induced the expression of canonical stress responsive genes. Silencing of BrERF109 in Chinese cabbage by virus-induced gene silencing (VIGS) led to plants’ susceptibility to drought and salt stress, and suppressed superoxide dismutase and peroxidase activities. Furthermore, BrLTP3, BrCIPK6, BrAZF2, and BrZAT10 genes containing GCC-box in their promoter regions were identified as downstream candidate targets of BrERF109. Overall, our study demonstrated that BrERF109 is a key positive regulator in response to drought and salt stress in Chinese cabbage, and serves as a valuable target gene for breeding new cultivars with enhanced tolerances to abiotic stresses in Brassica vegetables.

Insights into the alleviation of cadmium toxicity in rice by nano-zinc and Serendipita indica: Modulation of stress-responsive gene expression and antioxidant defense system activation

The adversities of cadmium (Cd) contamination are quite distinguished among other heavy metals (HMs), and so is the efficacy of zinc (Zn) nutrition in mitigating Cd toxicity. Rice (Oryza sativa) crop, known for its ability to absorb HMs, inadvertently facilitates the bioaccumulation of Cd, posing a significant risk to both the plant itself and to humans consuming its edible parts, and damaging the environment as well. The use of nanoparticles, such as nano-zinc oxide (nZnO), to improve the nutritional quality of crops and combat the harmful effects of HMs, have gained substantial attention among scientists and farmers. While previous studies have explored the individual effects of nZnO or Serendipita indica (referred to as S.i) on Cd toxicity, the synergistic action of these two agents has not been thoroughly investigated. Therefore, the gift of nature, i.e., S. indica, was incorporated alongside nZnO (50 mg L−1) against Cd stress (15 μM L−1) and their alliance manifested as phenotypic level modifications in two rice genotypes (Heizhan43; Hz43 and Yinni801; Yi801). Antioxidant activities were enhanced, specifically peroxidase (61.5 and 122.5% in Yi801 and Hz43 roots, respectively), leading to a significant decrease in oxidative burst; moreover, Cd translocation was reduced (85% for Yi801 and 65.5% for Hz43 compared to Cd alone treatment). Microstructural study showed a decrease in number of vacuoles and starch granules with ameliorative treatments. Overall, plants treated with nZnO displayed gene expression pattern (particularly of ZIP genes), different from the ones with alone or combined S.i and Cd. Inferentially, the integration of nZnO and S.i holds great promise as an effective strategy for alleviating Cd toxicity in rice plants. By immobilizing Cd ions in the soil and promoting their detoxification, this novel approach contributes to environmental restoration and ensures food safety worldwide.

Seaweed extract ameliorates salt stress in tomato plants by enhancing the antioxidant system and expression of stress-responsive genes

Seaweed extract ameliorates salt stress in tomato plants by enhancing the antioxidant system and expression of stress-responsive genes

GhMAPK3, a mitogen-activated protein kinase, enhance salt and drought tolerance in cotton (Gossypium hirsutum)

Multiple abiotic stresses, such as drought and high salinity, seriously limit cotton production. However, the mitogen-activated protein kinases (MAPKs) could play a critical role in responding to multiple environmental abiotic stresses. In this study, one of the MAPKs in cotton, GhMAPK3 (GH_D03G1517), was cloned and its role in drought and salt stress tolerance was investigated. The qRT-PCR assays demonstrated that GhMAPK3 predominantly expressed in leaf and root parts and showed higher expression under salt and drought stress. Subcellular localization assays revealed that GhMAPK3 was distributed in the nucleus and cytoplasm. The silenced of GhMAPK3 could decrease the tolerance of cotton plants under salt and drought stress via virus-induced gene silencing (VIGS) experiments. In GhMAPK3-slienced plants, the expression of stress-responsive genes has been revealed to be down-regulated levels, while the oxidants and antioxidant enzymes showed relatively higher levels and relatively lower levels, respectively. We further acquired three GhMAPK3 overexpression Arabidopsis lines, and they showed higher drought and salt tolerance than the wild-type (WT) plants, the chlorophyll content and relative leaf water content were found to be relatively stable through GhMAPK3 overexpressed plants under the abiotic stress. Further investigation revealed that GhMAPK3 showed a higher germination rate and longer root length under salt and drought stress. Overall, our findings revealed that the GhMAPK3 gene plays a prominent role in drought and salt tolerance and offers knowledge on crop genetic improvements.

A Comprehensive Analysis of the Peanut SQUAMOSA Promoter Binding Protein-like Gene Family and How AhSPL5 Enhances Salt Tolerance in Transgenic Arabidopsis.

SPL (SQUAMOSA promoter binding protein-like), as one family of plant transcription factors, plays an important function in plant growth and development and in response to environmental stresses. Despite SPL gene families having been identified in various plant species, the understanding of this gene family in peanuts remains insufficient. In this study, thirty-eight genes (AhSPL1-AhSPL38) were identified and classified into seven groups based on a phylogenetic analysis. In addition, a thorough analysis indicated that the AhSPL genes experienced segmental duplications. The analysis of the gene structure and protein motif patterns revealed similarities in the structure of exons and introns, as well as the organization of the motifs within the same group, thereby providing additional support to the conclusions drawn from the phylogenetic analysis. The analysis of the regulatory elements and RNA-seq data suggested that the AhSPL genes might be widely involved in peanut growth and development, as well as in response to environmental stresses. Furthermore, the expression of some AhSPL genes, including AhSPL5, AhSPL16, AhSPL25, and AhSPL36, were induced by drought and salt stresses. Notably, the expression of the AhSPL genes might potentially be regulated by regulatory factors with distinct functionalities, such as transcription factors ERF, WRKY, MYB, and Dof, and microRNAs, like ahy-miR156. Notably, the overexpression of AhSPL5 can enhance salt tolerance in transgenic Arabidopsis by enhancing its ROS-scavenging capability and positively regulating the expression of stress-responsive genes. These results provide insight into the evolutionary origin of plant SPL genes and how they enhance plant tolerance to salt stress.

Oxidized guanosines induce mitochondrial dysfunction and loss of viability in β-cells

The production of reactive oxygen species and oxidative stress promote β-cell dysfunction and impair insulin secretion, thereby contributing to the pathogenesis of type 2 diabetes mellitus (T2DM). The nucleobase guanine is highly sensitive to oxidation, which results in the formation of 8-oxoguanosine (8oxoG) and 8-oxodeoxyguanosine (8oxodG). The urinary excretion of 8oxoG is associated with the risk of mortality in people with T2DM, including from diabetic complications such as cardiovascular disease. However, the cellular mechanisms responsible for this association are poorly defined. Therefore, in this study, we examined the effect of 8oxoG, 8oxodG and other oxidized guanosine derivatives, on the INS-1E β-cell line. Exposure of INS-1E cells to 8oxoG and 8oxodG decreased metabolic activity and promoted cell death by apoptosis. The change in cell viability was similar to that induced by treatment of INS-1E cells with the inflammatory cytokines interleukin 1β (Il-1β) and tumour necrosis factor α (TNFα). Changes in mitochondrial membrane permeability and superoxide radical formation were also observed with 8oxoG, but there was no significant change in the oxidation state of mitochondrial cytochromes or hydrogen peroxide levels in the INS-1E cells. Interestingly, exposure to 8oxoG and 8-oxodG also increased the mRNA expression of stress response genes, including NADPH dehydrogenase quinone 1 (NQO1), and thioredoxin-interacting protein (TXNIP). Together, these results support a potential role of oxidized guanosine derivatives in the induction of β-cell dysfunction, which could be relevant to the pathogenesis of T2DM.