Distinct Regulation Research Articles

Inventory optimisation in a two-echelon cold chain: Sustainable lot-sizing and shipment decisions under carbon cap emissions regulations

Abstract Cold chains are a major source of carbon emissions because they make use refrigerated trucks and warehouses for distribution and storage of inventory. Consequently, inventory management in cold chains should prioritise both profitability and environmental sustainability. This paper optimises inventory in a cold chain system consisting of a single warehouse and retail outlet, responsible for storing and selling cold items, respectively. To maintain product quality and safety, these items must be transported and stored in temperature-controlled environments. Two inventory models for the proposed cold chain are formulated and compared under two distinct carbon emissions regulations, namely, cap-and-trade and cap-and-offset, using both financial and environmental metrics. The proposed models factor in carbon emissions from refrigerated trucks and warehouses used for transporting and storing cold inventory. This study examines both a numerical example and a real case study involving a frozen seafood supply chain. The numerical analysis reveals that cap-and-trade regulation is more effective in reducing environmental impact, leading to 4.4% lower carbon emissions compared to carbon cap-and-offset regulation. However, from an economic standpoint, carbon cap-and-offset regulation performs marginally better, generating a 1% higher profit. The study identifies three key factors that significantly influence both financial and environmental outcomes in the cold chain: truck capacity, fuel efficiency, and freezer performance. As a result, management can best improve profitability and reduce emissions in cold chain operations by focusing on optimising these critical elements.

Chromatin landscape alteration uncovers multiple transcriptional circuits during memory CD8+ T cell differentiation.

Extensive epigenetic reprogramming involves in memory CD8+ T-cell differentiation. The elaborate epigenetic rewiring underlying the heterogeneous functional states of CD8+ T cells remains hidden. Here, we profile single-cell chromatin accessibility and map enhancer-promoter interactomes to characterize the differentiation trajectory of memory CD8+ T cells. We reveal that under distinct epigenetic regulations, the early activated CD8+ T cells divergently originated for short-lived effector and memory precursor effector cells. We also uncover a defined epigenetic rewiring leading to the conversion from effector memory to central memory cells during memory formation. Additionally, we illustrate chromatin regulatory mechanisms underlying long-lasting versus transient transcription regulation during memory differentiation. Finally, we confirm the essential roles of Sox4 and Nrf2 in developing memory precursor effector and effector memory cells, respectively, and validate cell state-specific enhancers in regulating Il7r using CRISPR-Cas9. Our data pave the way for understanding the mechanism underlying epigenetic memory formation in CD8+ T-cell differentiation.

Deacetylated SNAP47 recruits HOPS to facilitate autophagosome-lysosome fusion independent of STX17

Autophagy, a conserved catabolic process implicated in a diverse array of human diseases, requires efficient fusion between autophagosomes and lysosomes to function effectively. Recently, SNAP47 has been identified as a key component of the dual-purpose SNARE complex mediating autophagosome-lysosome fusion in both bulk and selective autophagy. However, the spatiotemporal regulatory mechanisms of this SNARE complex remain unknown. In this study, we found that SNAP47 undergoes acetylation followed by deacetylation during bulk autophagy and mitophagy. The acetylation status of SNAP47 is regulated by the acetyltransferase CBP and the deacetylase HDAC2. Notably, the spatiotemporal regulatory dynamics of SNAP47 acetylation differ between bulk autophagy and mitophagy due to distinct regulation on the activity of acetyltransferase and deacetylase. Acetylated SNAP47 inhibits autophagosome-lysosome fusion by indirectly impeding SNARE complex assembly. Mechanistically, deacetylated SNAP47 recruits HOPS components to autophagic vacuoles independently of STX17 and STX17-SNAP47 interaction, while acetylated SNAP47 inhibits this recruitment, consequently leading to the failure of SNARE complex assembly. Taken together, our study uncovers a SNAP47 acetylation-dependent regulatory mechanism governing autophagosome-lysosome fusion by modulating the recruitment of HOPS to autophagic vacuoles without involving STX17, SNAP47-STX17 interaction and ternary SNARE complex formation.

Distinct dynamic regulation of pectoralis muscle metabolomics by insulin and the promotion of glucose-lipid metabolism with extended duration

Birds' glycolipid metabolism has garnered considerable attention due to their fasting blood glucose levels being nearly twice those of mammals. While skeletal muscle is the primary insulin-sensitive tissue in mammals, the effects of insulin on chicken skeletal muscle remain unclear. In this study, the insulin-responsive metabolites were identified in broiler's pectoralis muscle (after 16 h of fasting) using widely targeted metabolomics. Glycolipid concentrations were measured using kits, and the expression of key genes involved in glucose metabolism was assessed via quantitative real-time PCR (qRT-PCR). The insulin tolerance test, performed by injecting 5 IU/kg body weight of insulin, demonstrated a rapid drop in blood glucose levels from 0 to 15 min, with a consistent reduction observed at 120 min (P < 0.01). Insulin did not alter glucose and glycogen content in chicken pectoralis; however, low-density lipoprotein (LDL, P < 0.05) levels were upregulated in the early phase (15 min). With an extended insulin duration (120 min), pectoralis glucose content increased (P < 0.05), accompanied by a reduction in TG levels (P < 0.05). Metabolomic analysis revealed that insulin promotes the downregulation of 63 out of 71 metabolites at 15 min and the upregulation of 101 out of 134 metabolites at 120 min, mainly associated with lysine degradation and thyroid hormone signaling pathways, respectively. 7 metabolites were dynamically modulated in the same manner over time (2 up-up and 5 down-down). Early insulin inhibited glycolysis, evidenced by the reduction in phosphoenolpyruvate levels and hexokinase 2 (HK2) expression; however, insulin promoted glucose uptake through the activation of glucose transporter 4 (GLUT4) and enhanced glycolysis, accompanied by elevated fatty acid metabolism at the later phase. In conclusion, insulin dynamically regulates the metabolomics of the pectoralis muscle over time. Initially, chicken muscle tissues downregulate metabolic activities to accommodate the new signaling state, followed by significant upregulation to meet heightened metabolic demands. Extended insulin monitoring promotes glucose uptake and glycolysis, alongside enhanced fatty acid metabolism. This research provides insights into the potential mechanisms of insulin action in chicken muscles.

A tale of two endothelins: the rise and fall of the corpus luteum.

Endothelins are small 21 amino acid peptides that interact with G-protein-coupled receptors. They are highly conserved across species and play important roles in vascular biology as well as in disease development and progression. Endothelins, mainly endothelin-1 and endothelin-2, are intricately involved in ovarian function and metabolism. These two peptides differ only in two amino acids but are encoded by different genes, which suggests an independent regulation and a cell-specific mode of expression. This review aims to comprehensively discuss the distinct regulation and roles of endothelin-1 and endothelin-2 regarding corpus luteum function throughout its life span.

A Comparative Analysis and Development of Legislative Regulatory Framework of Naturopathy and Traditional Medicines Practices in Southern Africa Region

Objectives: Law and policy are critical instruments for enhancing health systems. The development of modern medicine relies heavily on stringent laws and policies. Additionally, the legislative framework for naturopathy and traditional complementary alternative medicines emphasizes the registration of both products and practitioners. This paper aims to examine the legislative regulatory framework governing naturopathic practices and other traditional complementary medicines in the Southern African region. Methods: This study involves a comprehensive review of various health laws and policy documents across Southern African countries. A country-specific analysis is conducted using keywords such as "naturopathic law," "naturopathic medicine practice," "legislation," "traditional medicine act," "alternative medicine act," and "healthcare laws." Results: The findings indicate that Southern African nations have well-established laws pertaining to naturopathy, as well as distinct regulations for traditional medicine. These countries recognize naturopathy and other complementary therapies as part of allied health professions. Moreover, there is a minimum educational requirement for registration as a traditional medicine healer, which applies to alternative complementary medicines. Conclusions: The research reveals that specific laws regulating naturopathic practice exist in Southern African countries. This commentary on the legislative regulatory framework for naturopathic and other traditional complementary medicines aims to inform public health decisions in Africa.

Interfering Nuclear Protein Laminb1 Induces DNA Damage and Reduces Vemurafenib Resistance in Melanoma Cells In Vitro.

Drug resistance poses a substantial clinical challenge in melanoma treatment, yet the underlying mechanism remains elusive. Here, we report the novel role of laminB1, a nuclear structure protein, in regulating the response of BRAF-mutated melanoma cells to vemurafenib. Our analysis of clinical samples and existing databases highlights the tight correlation between the laminB1 expression level and melanoma progression and prognosis. Notably, we observe that laminB1 expression is upregulated when BRAF-mutated melanoma cells develop resistance to vemurafenib. The knockdown of laminB1 substantially increases the sensitivity of melanoma cells to vemurafenib. Furthermore, we found laminB1 suppression increases cell apoptosis via the escalation of DNA damage in a vemurafenib-dose-dependent manner. Conversely, protective cell autophagy is negatively regulated by laminB1 suppression. Interestingly, this distinct regulation pattern of apoptosis and autophagy by laminB1 cooperatively promotes the response of BRAF-mutated melanoma cells to vemurafenib. Our findings unveil the potential of laminB1 as both a diagnosis marker and a therapeutic target of melanoma.

Tubulin sequence divergence is associated with the use of distinct microtubule regulators.

Diverse eukaryotic cells assemble microtubule networks that vary in structure and composition. While we understand how cells build microtubule networks with specialized functions, we do not know how microtubule networks diversify across deep evolutionary timescales. This problem has remained unresolved because most organisms use shared pools of tubulins for multiple networks, making it difficult to trace the evolution of any single network. In contrast, the amoeboflagellate Naegleria expresses distinct tubulin genes to build distinct microtubule networks: while Naegleria builds flagella from conserved tubulins during differentiation, it uses divergent tubulins to build its mitotic spindle. This genetic separation makes for an internally controlled system to study independent microtubule networks in a single organismal and genomic context. To explore the evolution of these microtubule networks, we identified conserved microtubule-binding proteins and used transcriptional profiling of mitosis and differentiation to determine which are upregulated during the assembly of each network. Surprisingly, most microtubule-binding proteins are upregulated during only one process, suggesting that Naegleria uses distinct component pools to specialize its microtubule networks. Furthermore, the divergent residues of mitotic tubulins tend to fall within the binding sites of differentiation-specific microtubule regulators, suggesting that interactions between microtubules and their binding proteins constrain tubulin sequence diversification. We therefore propose a model for cytoskeletal evolution in which pools of microtubule network components constrain and guide the diversification of the entire network, so that the evolution of tubulin is inextricably linked to that of its binding partners.

Differential Transcriptome Reprogramming Induced by the Soybean Cyst Nematode Type 0 and Type 1.2.5.7 During Resistant and Susceptible Interactions.

Soybean cyst nematode (SCN, Heterodera glycines [Hg]) is a serious root parasite of soybean (Glycine max) that induces extensive gene expression changes associated with pleiotropic biological activities in infected cells. However, the impacts of various SCN Hg types on host transcriptome reprogramming remain largely unknown. Here, we developed and used two recombinant inbred lines (RIL; RIL-72 and RIL-137) to profile transcriptome reprogramming in the infection sites during the resistant and susceptible interactions with SCN Hg Type 1.2.5.7 and Type 0. SCN bioassays indicated that RIL-72 was susceptible to Type 1.2.5.7 but resistant to Type 0, whereas RIL-137 was resistant to both types. Comparative analysis of gene expression changes induced by Type 1.2.5.7 in the resistant and susceptible lines revealed distinct transcriptome regulation with a number of similarly and oppositely regulated genes. The expression levels of similarly regulated genes in the susceptible line appeared to be insufficient to mount an effective defense against SCN. The functional importance of oppositely regulated genes was confirmed using virus-induced gene silencing (VIGS) and overexpression approaches. Further transcriptome comparisons revealed shared as well as Hg type- and genotype-specific transcriptome reprogramming. Shared transcriptome responses were mediated through common SCN-responsive genes and conserved immune signaling, whereas genotype-specific responses were derived from genetic variability, metabolic and hormonal differences, and varied regulation of protein phosphorylation and ubiquitination. The conserved defense mechanisms together with genotype-specific responses would enable plants to trigger effective and tailored immune responses to various Hg types and adapt the defense response to their genetic backgrounds. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Leaf carbohydrate metabolic enzyme activities are associated with salt tolerance and yield stability in the climate-resilient crop Camelina sativa

Soil salinity is an increasingly severe problem affecting plant growth and development thus posing a threat to agricultural production worldwide. Many crops currently grown are susceptible to even moderate salt stress, and crop diversification is sought to cope with increasingly challenging environmental conditions. Camelina sativa is a versatile, underutilized, low-input Brassicaceae oilseed crop valued for its high-quality seeds and its resilience to a wide range of climate conditions. In this study, the effects of salt stress on the growth and productivity of two camelina cultivars and six landraces from different geographic regions were examined. The performance of these lines was related to adjustments in their carbohydrate metabolic enzyme activity profiles in leaves as a central physiological hub. Profiling enzyme activities and their regulation in response to salt stress revealed significant genotype × treatment (G × T) interactions and allowed the identification of specific activity signatures associated with differences in yield stability in the tested lines. Yield-stable landraces showed distinct regulation patterns contrasting those of less yield-stable lines. In particular, upregulation of specific enzyme activities was associated with yield stability under salt stress. Camelina landraces may be promising resources to improve tolerance to salinity, with plasticity in carbohydrate metabolism as a contributing mechanism. Overall, these results provide a valuable basis for enzyme activity signatures as new physiological markers for supporting breeding programmes.

Multi-Omics Analyses Offer Novel Insights into the Selection of Sugar and Lipid Metabolism During Maize Domestication and Improvement.

Over thousands of years of domestication, maize has undergone significant environmental changes. Understanding the genetic and metabolic trace during maize evolution can better contribute to molecular breeding and nutrition quality improvement. This study examines the metabolic profiles and transcriptomes of maize kernels from teosinte, landrace, and maize accessions at 15 days post-pollination. Differentially accumulated metabolites were enriched in sugar and lipid metabolism pathways. The metabolic selection profile exhibited four distinct patterns: continuous increases, constant decrease, initial decline or stability followed by an increase, and initial growth or stability followed by a subsequent decline. Sugars and JA were positive selection while LPCs/LPEs were negative selection during evolution. The expression level of genes related to sugar accumulation was significantly higher in maize, contrasting with enhanced glycolysis and lipid metabolism activity in teosinte. The correlation network highlighted distinct hormonal regulation of sugar and lipid metabolism. We identified 27 candidate genes associated with sugar, lipid, and JA that have undergone strong selection by population genomic regions. The positive selection of the PLD may explain the negative selection of LPCs/LPEs due to substrate competition. These findings enhance our understanding of the evolutionary trajectory of primary metabolism in maize and provide valuable resources for breeding and improvement.

Distinct Requirements for CD4+ T Cell Help for Immune Responses Induced by mRNA and Adenovirus-Vector SARS-CoV-2 Vaccines.

CD4+ T cells have been established as central orchestrators of cellular and humoral immune responses to infection or vaccination. However, the need for CD4+ T cell help to generate primary CD8+ T cell responses is variable depending on the infectious agent or vaccine and yet consistently required for the recall of CD8+ T cell memory responses or antibody responses. Given the deployment of new vaccine platforms such as nucleoside-modified mRNA vaccines, we sought to elucidate the requirement for CD4+ T cell help in the induction of cellular and antibody responses to mRNA and adenovirus (Ad)-vectored vaccines against SARS-CoV-2. Using antibody-mediated depletion of CD4+ T cells in a mouse immunization model, we observed that CD4+ T cell help was dispensable for both primary and secondary CD8+ T cell responses to the BNT162b2 and mRNA-1273 mRNA vaccines but required for the AZD1222 Ad-vectored vaccine. Nonetheless, CD4+ T cell help was needed by both mRNA and Ad-vectored vaccine platforms for the generation of antibodies, demonstrating the centrality of CD4+ T cells in vaccine-induced protective immunity against SARS-CoV-2. Ultimately, this highlights the shared and distinct regulation of humoral and cellular responses induced by these vaccine platforms.

Sex Difference in Histopathological and Steroidogenesis Metabolism of Zebrafish After Exposure to Spiromesifen.

Spiromesifen (SPM) is widely used for orchard mites and white fly control. The ecotoxicological data suggested that SPM is highly toxic to fish, but the information about its toxic effect on zebrafish is still obscure. In this study, adult zebrafish were exposed to SPM for 21 days. The plasma sex steroid hormone levels reflected the ratio of 17β-estradiol (E2) to testosterone (T) (E2/T) was significantly increased at 0.50 μg/L of SPM in male fish (2.4-fold, p = 0.049). Following 21 days' post exposure, distinct pathological changes were noted in gonad, males were more sensitive than female, which showed the interstitial connective tissue hyperplasia and widener in testis at 15 μg/L of SPM. In male fish, the relative percentage of spermatozoa was 13% decreased at 30 μg/L of SPM (p = 0.041). Which suggest SPM potential role in disrupting male gonad development. qRT-PCR results suggest that expression of follicle stimulating hormone receptor (fshr) was significantly down regulated in female zebrafish (0.29 fold of control, p = 0.010). Variable importance of projection (VIP) scores indicate the most important features separate in female and male. The different response of steroid level towards SPM between male and female zebrafish may due to the distinct regulation of key genes related in steroidogenesis and metabolism. This study for the first time connects the biochemical and histological to reveal the adverse effects of SPM on adult zebrafish in a sex dependent manner.

An improved transcriptome annotation reveals asymmetric expression and distinct regulation patterns in allotetraploid common carp

In allotetraploid common carp, protein-coding homoeologs presented divergent expression levels between the two subgenomes. However, whether subgenome dominance occurs in other transcriptional and post-transcriptional events remains unknown. Using Illumina RNA sequencing and PacBio full-length sequencing, we refined the common carp transcriptome annotation and explored differences in four transcriptional and post-transcriptional events between the two subgenomes. The results revealed that the B subgenome presented more alternative splicing events, as did lncRNAs and circRNAs. However, the expression levels, tissue specificity, sequence features, and functions of lncRNAs and circRNAs did not significantly differ between the two subgenomes, suggesting a common regulatory mechanism shared by the two subgenomes. Furthermore, both the number and base substitution frequency of RNA editing events were greater in the B subgenome. Functional analyses of these transcriptional events also revealed subgenome bias. Genes that undergo alternative splicing in the A subgenome participate in more biological processes, and lncRNA targets show a preference between subgenomes. CircRNA host genes in the B subgenome were associated with more biological functions, and RNA editing preferentially occurred in noncoding regions or led to nonsynonymous mutations in the B subgenome. Taken together, the refined transcriptome annotation revealed complicated and imbalanced expression strategies in allotetraploid common carp.

Integration of Single-Cell and Spatial Transcriptomic Data Reveals Spatial Architecture and Potential Biomarkers in Alzheimer's Disease.

Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by the gradual loss of neurons and the accumulation of amyloid plaques and neurofibrillary tangles. Despite advancements in the understanding of AD's pathophysiology, the cellular organization and interactions in the prefrontal cortex (PFC) remain elusive. Eight single-cell RNA sequencing (scRNA-seq) datasets from both normal controls and individuals with AD were harmonized. Stringent preprocessing protocols were implemented to uphold dataset integrity. Unsupervised clustering and annotation revealed 22 distinct cell clusters corresponding to 19 unique cell types. The spatial architecture of the PFC region was constructed using the CARD tool. Further analyses encompassed trajectory examination of Oligodendrocyte subtypes, evaluation of regulon activity scores, and spot clustering within white matter regions (WM). Differential expression analysis and functional enrichment assays unveiled molecular signatures linked to AD progression and were validated using microarray data sourced from neurodegenerative disorder patients. Our investigation employs scRNA-seq and spatial transcriptomics to uncover the cellular atlas and spatial architecture of the human PFC in AD. Moreover, our results indicate that Oligodendrocytes are more prevalent in AD patients, showcasing diverse subtypes and spatial organization within WM regions. Each subtype appears to be associated with distinct biological processes and transcriptional regulators, shedding light on their involvement in AD pathology. Notably, the Oligodendrocyte_C6 subtype is linked to neurological damage in AD patients, characterized by heightened expression of genes involved in cell-cell connections, cell membrane stability, and myelination. Additionally, 12 target genes regulated by NFIA were identified, which are upregulated in AD patients and associated with disease progression. Elevated PLXDC2 expression in peripheral blood was also identified, suggesting its potential as a non-invasive biomarker for early AD detection. Our study provides novel insights into the role of Oligodendrocytes in AD and highlights the potential of PLXDC2 as a blood biomarker for non-invasive diagnosis and monitoring of AD patients.

Differentiated Intra-Ligand Charge Transfer Boosting Multicolor Responsive MOF Heterostructures as Robust Anti-Counterfeiting Labels.

Metal-organic framework (MOF) heterostructures with hybrid architectures and abundant functional sites possess great potential applications in advanced information security, yet still suffer from the harsh stimuli mechanisms with restrained emission control. Herein, the differentiated design strategy on intra-ligand charge transfer is first reported to realize smart-responsive multicolor MOF heterostructures as robust anticounterfeiting labels. Designed similar MOF blocks with the differentiated intra-ligand charge transfer are integrated via time-dependent epitaxial growth to form multicolor MOF heterostructures. Different numbers of electron-donating groups in MOF blocks offer distinct space regulation on the torsion of charge transfer ligands, which trigger the diverse responsive emissions under the same mild stimuli, thus generating multiple tunable color patterns in heterostructures. These spatial-resolved MOF heterostructures with stable multicolor responsive modes permit the encoding of fingerprint information, which further functions as robust anti-counterfeiting labels with high-security convert states. These results offer a promising route for the function-oriented exploitation of smart-responsive MOF heterosystems for advanced information anticounterfeiting.

From biomass to power: High-performance reactor design for coking-resistant operation

Biomass gasification coupled with solid oxide fuel cell (SOFC) technology utilizes the gas generated from biomass gasification directly as fuel for SOFC, thereby realizing power generation from solid waste. This technology combines the carbon–neutral feature of biomass with the high efficiency and low emissions of SOFC, making it a promising route for clean energy generation. However, biomass gasification syngas possesses a complex composition, including a high concentration of inert gases, which imposes higher requirements on SOFC. This study developed a multi-channel, hierarchical structural design based on the commercial NiO-yttria-stabilized zirconia (YSZ) material system, realizing high-performance power generation using biomass gasification syngas. The results showed that the combination of a unique structural design and an enhanced interface electrochemical reaction effectively mitigates the influence from inert composition dilution. When operating in gasification syngas with nearly 60 % inert components, the power density can reach 2.07 W·cm−2 (750 °C). In addition, due to the spatial separation of the inert support region and the electrochemically active region, the effect of controlling the position of carbon deposits was achieved, demonstrating 100 h stable operation with dry biomass gasification syngas. Hence, the combination of micro-tubular SOFC with distinctive structural regulation and biomass gasification exhibits promising prospects for further development.

Novel motif associated with carbon catabolite repression in two major Gram-positive pathogen virulence regulatory proteins.

Carbon catabolite repression (CCR) is a widely conserved regulatory process that ensures enzymes and transporters of less-preferred carbohydrates are transcriptionally repressed in the presence of a preferred carbohydrate. This phenomenon can be regulated via a CcpA-dependent or CcpA-independent mechanism. The CcpA-independent mechanism typically requires a transcriptional regulator harboring a phosphotransferase regulatory domain (PRD) that interacts with phosphotransferase system (PTS) components. PRDs contain a conserved histidine residue that is phosphorylated by the PTS-associated HPr-His15~P protein. PRD-containing regulators often harbor additional domains that resemble PTS-associated EIIB protein domains with a conserved cysteine residue that can be phosphorylated by cognate PTS components. We noted that Mga, the PRD-containing central virulence regulator of Streptococcus pyogenes, has an EIIBGat domain containing a cysteine that, based on the presence of a similar motif in glycerol kinase, could be a target for phosphorylation. Using site-directed mutagenesis, we constructed phospho-ablative and phospho-mimetic substitutions of this cysteine and found that these substitutions modify the CCR of the Rgg2/3 quorum-sensing system. Moreover, we provide genetic evidence that the phospho-donor of this cysteine residue is likely to be ManL, the EIIA/B subunit of the mannose PTS system. Interestingly, a structurally distinct virulence gene regulator, PrfA of Listeria monocytogenes, harbors a similar cysteine-containing motif, and phospho-ablative and phospho-mimetic substitutions of the cysteine-altered CCR of PrfA-dependent virulence gene expression. Collectively, our data suggest that phosphorylation of a cysteine within the shared novel motif in Mga and PrfA may be a heretofore missing link between cellular metabolism and virulence.IMPORTANCEIn this study, we identified a novel cysteine-containing motif within the amino acid sequence of two structurally distinct transcriptional regulators of virulence in two Gram-positive pathogens that appears to link carbon metabolism with virulence gene expression. The results also highlight the potential post-translational modification of cysteine in bacterial species, a rare and understudied modification.

Trivalent chromium stress trigger accumulation of secondary metabolites in rice plants: Integration of biochemical and transcriptomic analysis

Trivalent chromium [Cr (III)] is a frequently detected environmental contaminant that negatively affects plant metabolism, growth, and yield. Plant secondary metabolites are non-nutrient compounds involved in diverse physiological functions in response to abiotic stresses. This study performed biochemical and transcriptomic analyses to clarify the protective role and mechanism of secondary metabolites in rice seedlings under Cr(III) stress. The content of measured secondary metabolites i.e., total soluble phenolics, flavonoids, lignin, and anthocyanin in rice tissues was significantly enhanced under Cr(III) exposure. Additionally, the activities of several enzymes including chalcone synthase, phenylalanine ammonialyase, peroxidase, and anthocyanidin synthase, were positively activated. Transcriptomic analysis revealed a number of differentially expressed genes (DEGs) in Cr(III)-treated rice seedlings and their expression patterns are tissue-specific. Additionally, the DEGs involved in secondary metabolism pathways were evident after KEGG enrichment analysis. Cr(III) exposure resulted in distinct genetic regulation strategies in rice tissues, with different DEGs activating various sub-pathways in the secondary metabolism pathways to cope with Cr(III) stress. Furthermore, the integrated correlation analysis of the secondary metabolites and transcriptome data identified key genes involved in different steps of the sub-pathways of secondary metabolism pathway in rice plants under Cr(III) stress. This study indicates that the accumulation of secondary metabolites in rice plants is a survival and detoxification strategy to reduce the adverse effects of toxic compounds. Future research should explore how key genes in secondary metabolism pathways aid in Cr(III) detoxification and enhance crop stress tolerance.

Holobiont Traits Shape Climate Change Responses in Cryptic Coral Lineages.

As ocean warming threatens reefs worldwide, identifying corals with adaptations to higher temperatures is critical for conservation. Genetically distinct but morphologically similar (i.e. cryptic) coral populations can be specialized to extreme habitats and thrive under stressful conditions. These corals often associate with locally beneficial microbiota (Symbiodiniaceae photobionts and bacteria), obscuring the main drivers of thermal tolerance. Here, we leverage a holobiont (massive Porites) with high fidelity for C15 photobionts to investigate adaptive variation across classic ("typical" conditions) and extreme reefs characterized by higher temperatures and light attenuation. We uncovered three cryptic lineages that exhibit limited micro-morphological variation; one lineage dominated classic reefs (L1), one had more even distributions (L2), and a third was restricted to extreme reefs (L3). L1 and L2 were more closely related to populations ~4300 km away, suggesting that some lineages are widespread. All corals harbored Cladocopium C15 photobionts; L1 and L2 shared a photobiont pool that differed in composition between reef types, yet L3 mostly harbored unique photobiont strains not found in the other lineages. Assemblages of bacterial partners differed among reef types in lineage-specific ways, suggesting that lineages employ distinct microbiome regulation strategies. Analysis of light-harvesting capacity and thermal tolerance revealed adaptive variation underpinning survival in distinct habitats: L1 had the highest light absorption efficiency and lowest thermal tolerance, suggesting that it is a classic reef specialist. L3 had the lowest light absorption efficiency and the highest thermal tolerance, showing that it is an extreme reef specialist. L2 had intermediate light absorption efficiency and thermal tolerance, suggesting that is a generalist lineage. These findings reveal diverging holobiont strategies to cope with extreme conditions. Resolving coral lineages is key to understanding variation in thermal tolerance among coral populations, can strengthen our understanding of coral evolution and symbiosis, and support global conservation and restoration efforts.