Role In Adaptation Research Articles

Parental environment as a factor shaping salinity tolerance in halophyte Tripolium pannonicum L.

Parental environment can significantly influence a range of plant traits across different growth phases and developmental stages. The impact of parental salinity variability on offspring germination and environmental factor response still requires thorough investigation. Therefore, we investigated seeds of Tripolium pannonicum L. from low-saline (Cie) and high-saline (Ino) habitats to elucidate the germination potential and adaptation potential of progeny to varying salinity levels. Germination and growth experiments were conducted to analyze germination parameters, plant areas, water-related traits, the concentration of organic solutes, malondialdehyde, and the activity of crucial oxidative defence enzymes. In the germination experiment, Cie seeds demonstrated higher germination potential with longer germination time under 200–400 mM NaCl compare with Ino seeds. The Cie population achieved the highest shoot and roots area at 100 mM and 300 mM NaCl, respectively. The Ino population exhibited its highest shoot and roots area at 200 mM NaCl. The Ino population indicated an increase in stem cortex cell area at 400 mM NaCl. The Ino population enhanced the synthesis of osmolytes as part of the salinity tolerance mechanism. Antioxidant enzyme analysis indicated higher peroxidase activity in Ino and higher superoxide dismutase activity in Cie under salinity, suggesting distinct enzymatic roles in salinity adaptation between populations. Our findings highlight the critical role of parental environmental conditions in shaping progeny traits, enhancing germination potential, and enabling adaptation of progeny plants to diverse environmental niches. The study underscores population-specific responses to environmental factor, emphasizing the complexity of halophyte adaptation mechanisms to salinity.

Modulation of human-to-swine influenza a virus adaptation by the neuraminidase low-affinity calcium-binding pocket

Frequent interspecies transmission of human influenza A viruses (FLUAV) to pigs contrasts with the limited subset that establishes in swine. While hemagglutinin mutations are recognized for their role in cross-species transmission, the contribution of neuraminidase remains understudied. Here, the NA’s role in FLUAV adaptation was investigated using a swine-adapted H3N2 reassortant virus with human-derived HA and NA segments. Adaptation in pigs resulted in mutations in both HA (A138S) and NA (D113A). The D113A mutation abolished calcium (Ca2+) binding in the low-affinity Ca2+-binding pocket of NA, enhancing enzymatic activity and thermostability under Ca2+-depleted conditions, mirroring swine-origin FLUAV NA behavior. Structural analysis predicts that swine-adapted H3N2 viruses lack Ca2+ binding in this pocket. Further, residue 93 in NA (G93 in human, N93 in swine) also influences Ca2+ binding and impacts NA activity and thermostability, even when D113 is present. These findings demonstrate that mutations in influenza A virus surface proteins alter evolutionary trajectories following interspecies transmission and reveal distinct mechanisms modulating NA activity during FLUAV adaptation, highlighting the importance of Ca2+ binding in the low-affinity calcium-binding pocket.

BirdWingData: Wingspan and wing area data of birds compiled from multiple literature sources and original measurements

AbstractWing morphology plays a pivotal role in avian flight capabilities and ecological adaptations across diverse environments. Consequently, wing measurement data are used frequently in comparative analyses and hypothesis exploration to understand avian evolution. Among the parameters representing wing morphology, wingspan and wing area are relatively challenging to obtain compared to simpler measures such as wing length and hand‐wing index. This study aimed to enhance accessibility to existing wingspan and wing area data by compiling measurements from 25 literature sources, in addition to unpublished data. The dataset covers 856 species across 95 families and 28 orders. Although the inclusion proportion varies widely among orders, ranging from 0% to 100%, this initial dataset forms a foundation for a more comprehensive database on avian wing morphology. The complete dataset for this abstract published in the Data Paper section of the journal is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2024-04.1/jalter-en. The dataset will be updated continuously, with the latest version available on figshare in CSV and Microsoft Excel formats (https://doi.org/10.6084/m9.figshare.23537892.v2).

IDENTITY OF AN ENTERPRISE AS A DISTINCT VALUE IN A CULTURE OF HIGH TOLERANCE FOR UNCERTAINTY

The identity of an enterprise, once overlooked by theorists, has gained significant attention across multiple disciplines, including management, sociology, and economics. In today’s dynamic business landscape, especially within cultures of high tolerance for uncertainty, corporate identity has emerged as a crucial element for success. Such cultures, characterized by flexibility, openness to change, and risk acceptance, require companies to establish a strong identity to navigate uncertainty and maintain coherence. Corporate identity integrates values, goals, culture, and operational methods, ensuring the company remains distinct and trustworthy amid constant change. This research aims to explore the theoretical and practical aspects of corporate identity as a distinct value in a culture with high tolerance for uncertainty, emphasizing its role in strategic decision-making and adaptability. The study is based on an interdisciplinary theoretical framework, utilizing general and specialized scientific research methods. These methods, including system analysis, theoretical generalization, and qualitative approaches, were employed to highlight challenges related to corporate identity and offer solutions. The research also incorporates perspectives from psychology, sociology, and management to analyze how identity functions in uncertain environments. The study highlights several factors contributing to the importance of corporate identity: cultural diversity, mission and values, image and reputation, organizational culture, management style, innovation capacity, and communication processes. It was found that companies with a well-defined identity are better equipped to manage risks, adapt to market changes, and build long-term relationships with stakeholders. A strong corporate identity enhances employee motivation, stakeholder trust, and the ability to innovate, thereby fostering a competitive edge in uncertain environments. The findings underscore the significance of corporate identity as a strategic asset in managing uncertainty. In today’s globalized, rapidly changing market, businesses must prioritize the development and maintenance of a clear, cohesive identity to ensure resilience and sustainability. Future research should focus on further exploring the role of corporate identity in different cultural contexts and its impact on long-term competitiveness and innovation.

The homeostasis of ions and reactive oxygen species in root and shoot play crucial roles in the tolerance of alfalfa to salt alkali stress

High pH saline-alkali stress, mainly NaHCO3, limited the development of animal husbandry in Songnen Plain. Ion imbalance and reactive oxygen species (ROS) metabolism disorder caused by saline-alkali stress inhibited plant growth. In this study, we compared the differences in ion absorption, transport and ROS metabolism between saline-tolerant alfalfa (ZD) and saline-sensitive alfalfa (ZM) under NaHCO3 stress using physiology and transcripomics techniques. WGCNA analysis identified key genes associated with NaHCO3 stress-induced changes. NaHCO3 stress inhibited the absorption of K+ and Mg2+, but activated Ca2+ signal. Furthermore, ZD maintained higher K+, Mg2+ and Ca2+ contents and the K+/Na+ ratio than ZM, this is mainly related to the higher expression of proteins or channel-encoding genes involved in ion absorption and transport in ZD. Antioxidant enzyme systems can be activated in response to NaHCO3 stress. Peroxidase (EC 1.11.1.6), catalase (EC 1.11.1.7) and glutathione transferase (EC 2.5.1.18) activities were higher in ZD than ZM, and most genes encoding the relevant enzymes also demonstrated a stronger up-regulation trend in ZD. Although NaHCO3 stress inhibited Trx-Prx pathway, ZD related enzymes and their genes were also inhibited less than ZM. WGCNA results identified many genes involved in ion absorption, transport and antioxidant systems that play an important role in NaHCO3 stress adaptation. Collectively, ZD has the stronger ion homeostasis regulation and ROS scavenging ability, so it's more resistant to NaHCO3. The results provide theoretical guidance for further understanding of the molecular mechanism of NaHCO3 resistance and provide potential genes for research to improve saline-alkali tolerance in alfalfa.

Unveiling the Coordinated Action of DesK/DesR and YvfT/YvfU to Control the Expression of an ABC Transporter in Bacillus subtilis.

Two-component systems (TCSs) are vital signal transduction pathways ubiquitous among bacteria, facilitating their responses to diverse environmental stimuli. In Bacillus subtilis, the DesK histidine kinase thermosensor, together with the response regulator DesR, constitute a TCS dedicated to membrane lipid homeostasis maintenance. This TCS orchestrates the transcriptional regulation of the des gene, encoding the sole desaturase in these bacteria, Δ5-Des. Additionally, B. subtilis possesses a paralog TCS, YvfT/YvfU, with unknown target gene(s). In this work, we show that YvfT/YvfU controls the expression of the yvfRS operon that codes for an ABC transporter. Interestingly, we found that this regulation also involves the action of DesK/DesR. Notably, opposite to des, yvfRS transcription is induced at 37°C and not at 25°C. Our invivo and invitro experiments demonstrate that both YvfU and DesR directly bind to the operon promoter region, with DesR exerting its control over yvfRS expression in its unphosphorylated state. Our study uncovers an intriguing case of cross-regulation where two homologous TCSs interact closely to finely tune gene expression in response to environmental cues. These findings shed light on the complexity of bacterial signal transduction systems and their critical role in bacterial adaptability.

СОЦИАЛЬНАЯ ПРИРОДА ЮМОРА

The article is dedicated to the study of humor as a sociocultural phenomenon, which is formed and developed in the context of social interactions and structures. The paper analyzes the conceptual nature of humor, its functions in society, and the perception of different types of humor depending on cultural, gender, and age factors. By exploring humor as a tool of social connection, the author examines its influence on group interactions, as well as its role in social transformation and adaptation.

Progress in Research on Terpenoid Biosynthesis and Terpene Synthases of Lauraceae Species

Lauraceae, an important family of Angiospermae, comprises over 2500 species widely distributed in tropical and subtropical evergreen broad-leaved forests. This family is renowned for its rich resource of terpenoids, particularly monoterpenes, sesquiterpenes, and diterpenes. These compounds not only impart specific scents to Lauraceae species but also play crucial roles in plant growth, development, and environmental adaptation. These compounds also possess extensive bioactivities, such as antioxidant, antibacterial, anti-inflammatory, and neuroprotective effects, making them valuable in the fields of perfumery, cosmetics, food, and medicine, and thus holding significant economic value. Recent advancements in high-throughput technologies, especially genomics, transcriptomics, and metabolomics, have significantly advanced our knowledge of the chemical constituents and biosynthetic pathways of terpenoids in Lauraceae species. Such progress has also shed light on the diversity and functionality of the terpene synthases (TPSs) gene family, a key enzyme involved in terpenoid biosynthesis. This paper reviews the latest research findings on the biosynthetic pathways of terpenoids and their key enzyme-encoding gene families in Lauraceae plants. We also analyze the evolutionary patterns of TPS gene family members of four Lauraceae species at the whole-genome level and summarize their mechanisms of action in secondary metabolite synthesis. Furthermore, this paper highlights the current research challenges and proposes prospects, such as the complexity of gene families, the uncertainties in functional predictions, and unclear regulatory mechanisms. Our objective is to provide scientific foundations for the in-depth analysis of terpenoid biosynthesis mechanisms and the development and utilization of natural products in Lauraceae plants.

Genome-Wide Identification of Rubber Tree SCAMP Genes and Functional Characterization of HbSCAMP3.

Natural rubber produced by the rubber tree is a vital industrial raw material globally. Seven SCAMP gene family members were identified in the rubber tree, and the phylogenetic tree classified HbSCAMPs into three subfamilies. Significant differences were observed among HbSCAMPs in terms of gene length, number of exons, and composition of conserved motifs. The expansion of HbSCAMPs in the rubber tree genome is associated with segmental duplications. The high expression of HbSCAMP1-6 in petioles and HbSCAMP7 in stem tips, along with their distinct responses to drought, salt, and wound stresses, indicates their crucial roles in substance transport and stress adaptation. Transgenic poplar experiments demonstrated that overexpression of HbSCAMP3 significantly promotes plant height growth, with localization in the tobacco plasma membrane, suggesting its involvement in regulating plant growth through membrane transport processes. These findings enhance the understanding of HbSCAMPs in rubber trees and provide new insights into how plants finely tune gene family members to adapt to environmental changes.

Synergizing Sustainable Development: A Comprehensive Analysis of Circular, Blue, and Green Economy Integration

This paper explores the integration of circular, blue, and green economies to enhance sustainable development. By synthesizing insights from recent literature, the study examines how these economic models, each with its unique principles and practices, can be combined to address environmental, economic, and social challenges more effectively. The review highlights the complementarities and synergies between these models, focusing on their potential to improve resource efficiency, promote marine and coastal conservation, and support low-carbon technologies. Key findings include the benefits of aligning trade dynamics with sustainability goals, the importance of integrated energy, water, and environmental management, and the role of adaptation and mitigation strategies in climate action. The paper also discusses the challenges and opportunities associated with implementing these models, particularly in the context of regional and urban sustainability efforts. The integration of these approaches provides a comprehensive framework for achieving sustainability, demonstrating how coordinated strategies can lead to more resilient and effective solutions for global development.

Retrotransposon-driven environmental regulation of FLC leads to adaptive response to herbicide.

The mobilization of transposable elements is a potent source of mutations. In plants, several stransposable elements respond to external cues, fuelling the hypothesis that natural transposition can create environmentally sensitive alleles for adaptation. Here we report on the detailed characterization of a retrotransposon insertion within the first intron of the Arabidopsis floral-repressor gene FLOWERING LOCUS C (FLC) and the discovery of its role for adaptation. The insertion mutation augments the environmental sensitivity of FLC by affecting the balance between coding and non-coding transcripts in response to stress, thus expediting flowering. This balance is modulated by DNA methylation and orchestrated by IBM2, a factor involved in the processing of intronic heterochromatic sequences. The stress-sensitive allele of FLC has spread across populations subjected to recurrent chemical weeding, and we show that retrotransposon-driven acceleration of the life cycle represents a rapid response to herbicide application. Our work provides a compelling example of a transposable element-driven environmentally sensitive allele that confers an adaptive response in nature.

Rhizosphere bacterial community influence on <i>Deschampsia antarctica</i> È Desv. adaptability in context of temperature near plants in local spatial scales of Galindez Island, Argentine Islands (the maritime Antarctic)

The effect of rhizosphere bacterial community index (Irbi) influence on the nine populations of Antarctic hair grass (Deschampsia antarctica) adaptability was studied in the Galindez Island (summer season 2017/18). Moreover, the corresponding influence indices Irbi (i=1÷9) and Irbpi (p=1÷5 for the most common bacteria) were evaluated as well. The objective was to compare the Irbi and Irbpi series with the united temperature influence index on plant populations (It1i(z)) series and the united quality latent index of adaptability Iq1i. The study used data on the rhizosphere metagenome composition based on 16S RNA analysis. Methods determining the plant number in populations, and measuring the morphometric indices of D. antarctica populations were used. Reserve and protective seed proteins spectra were studied by polyacrylamide gel electrophoresis. Method of extreme grouping the spatial variables of these indices was applied for nine populations to obtain a Iq1I and It1i and Irbi, Irbpi. Sets of united indices were compared by regression technique. A comparative statistical analysis of the It1i and Irbi, Irbpi sets in this season was carried out. This possible influence appeared to be individual for each D. antarctica studied population. In each population, part of the plants reacted positively to the bacteria influence, while the other part either did not react or reacted negatively. Dependence of the plant adaptation indices on rhizospheric bacterial communities z(x) is shown in our data. This means that the rhizosphere bacterial community and temperature-dependent rhizosphere bacteria (x) can play an active role in plant adaptation of D. antarctica populations (z) to individual temperature conditions in the microscale of Galindez Island from a biological point of view.

The joint toxicity effect of glyphosate and cadmium in a concentration-dependent manner on nematode Caenorhabditis elegans

The co-occurrence of glyphosate (GPS), a commonly used organophosphorus herbicide, and cadmium (Cd), a neurotoxic metal, in agricultural environments prompts concerns about their combined toxic effects on ecosystems. This study explores the combined effects of GPS and Cd on the model organism Caenorhabditis elegans (C. elegans), to understand their cumulative effects in organismal living environments. We investigated the interaction between GPS and Cd over 24 hours using a comprehensive approach that included a variety of toxicity endpoints as well as the novel Automated Recognition and Statistics Tool (NCLE) for body bend measurement. Our data show a concentration-dependent interplay in which antagonistic effects at lower concentrations reduce phenotypic damage while synergistic effects emerge at higher concentrations, particularly at GPS's LC50. Transcriptome analysis under antagonistic conditions revealed significant downregulation of Cd toxicity-related genes and identified Y22D7AL.16, which has a C2H2-type zinc finger domain, as a novel gene involved in metal stress response, implying an alternative Cd-resilience mechanism. The expression profile of this gene shows that it plays a larger role in both development and metal stress adaption. These findings highlight the complexities of compound pollutant interactions, emphasizing the importance of including such dynamics in environmental risk assessments and control techniques.

Phosphorylation at the D56 residue of MtrA in Mycobacterium tuberculosis enhances its DNA binding affinity by modulating inter-domain interaction

The response regulator, MtrA, plays a major role in adaptation to the host environment, cell division, replication, and dormancy activation of Mycobacterium tuberculosis (Mtb). The phosphorylation of the response regulator MtrA alters the downstream activity, typically involving changes in DNA binding activity. However, there is a substantial knowledge gap in understanding the phosphorylation-mediated structural changes in MtrA. Additionally, the active conformation of the protein has yet to be determined. Therefore, in this study, we have investigated the phosphorylation-induced conformational changes of MtrA using all-atom molecular dynamics simulations under various phosphorylation conditions. The results from this study demonstrate that the phosphorylation at D56 (pD56-MtrA) increases the compactness of the MtrA protein by stabilizing the inter-domain interaction between the regulatory domain and DNA binding domain. Notably, the higher occupancy H-bond (over 95 %) between Arg200-Asn100 in case of the pD56-MtrA condition, which is otherwise absent in the non-phosphorylated (uMtrA) condition, suggests the importance of this interaction in the active conformation of the protein. The dynamic cross-correlation analysis reveals that phosphorylation (especially pD56-MtrA) reduces the anti-correlated motions and increases correlated motions between different domains. Moreover, the higher DNA binding affinity of pD56-MtrA compared to uMtrA supported by molecular docking and MD simulation followed by MMPBSA analysis suggests that pD56-MtrA is the possible active conformation of the MtrA protein. Overall, this investigation elucidates the key structural changes in MtrA under different phosphorylated conditions, which might help in designing novel therapeutics against tuberculosis.

Mechanisms conferring bacterial cell wall variability and adaptivity.

The bacterial cell wall, a sophisticated and dynamic structure predominantly composed of peptidoglycan (PG), plays a pivotal role in bacterial survival and adaptation. Bacteria actively modify their cell walls by editing PG components in response to environmental challenges. Diverse variations in peptide composition, cross-linking patterns, and glycan strand structures empower bacteria to resist antibiotics, evade host immune detection, and adapt to dynamic environments. This review comprehensively summarizes the most common modifications reported to date and their associated adaptive role and further highlights how regulation of PG synthesis and turnover provides resilience to cell lysis.

Hypoxia-Inducible Factor-1α Potentiates Multiterritory Perforator Flap Survival by Augmenting Vascular Endothelial Growth Factor Expression in the Choke II Zone.

Hypoxia-inducible factor-1α (HIF-1α), regulated by prolyl hydroxylase, plays a central role in tissue adaptation to ischemia. This study investigates the impact of HIF-1α on angiogenesis in the Choke II zone of multiterritory perforator flaps. Ninety male Wistar rats were allocated into 3 groups, with 30 rats in each group: the dimethyloxalylglycine (DMOG) group, the 3-(5-hydroxymethyl-2-furyl)-1-benzylindazole (YC-1) group, and the normal saline (NS) group. All rats underwent multiterritory perforator flap surgeries on their dorsal side. Subsequently, they received intraperitoneal injections of DMOG (40 mg/kg), YC-1 (10 mg/kg), and normal saline on postoperative days 1, 2, and 3, respectively. After treatment, angiogenesis in the Choke II zone of the flap on day 7 was observed through transillumination tests and lead oxide/gelatin x-ray angiography. Histological features were determined using hematoxylin and eosin staining, and the expression of HIF-1α and vascular endothelial growth factor (VEGF) in the Choke II region of the flap was assessed via immunohistochemistry and western blotting. Compared to the YC-1 and NS groups, the DMOG group exhibited significant angiogenesis, resulting in a denser vascular network in the Choke II zone of the flap. The DMOG group showed significantly higher microvessel density in the Choke II zone than the YC-1 and NS groups (7.10 ± 0.99 vs 24.30 ± 3.65; 14.30 ± 2.40 vs 24.30 ± 3.65, both P<0.05). Additionally, the DMOG group demonstrated higher expression of VEGF and HIF-1α in the flaps than the other groups (P < 0.05). In summary, HIF-1α enhances the expression of VEGF, promoting angiogenesis in the Choke II zone of the multiterritory perforator flap, thus increasing the survival area.

Loss of cardiomyocyte-specific adhesion G-protein-coupled receptor G1 (ADGRG1/GPR56) promotes pressure overload-induced heart failure.

Adhesion G-protein-coupled receptors (AGPCRs), containing large N-terminal ligand-binding domains for environmental mechano-sensing, have been increasingly recognized to play important roles in numerous physiologic and pathologic processes. However, their impact on the heart, which undergoes dynamic mechanical alterations in healthy and failing states, remains understudied. ADGRG1 (formerly known as GPR56) is widely expressed, including in skeletal muscle where it was previously shown to mediate mechanical overload-induced muscle hypertrophy; thus, we hypothesized that it could impact the development of cardiac dysfunction and remodeling in response to pressure overload. In this study, we generated a cardiomyocyte (CM)-specific ADGRG1 knockout mouse model, which, although not initially displaying features of cardiac dysfunction, does develop increased systolic and diastolic LV volumes and internal diameters over time. Notably, when challenged with chronic pressure overload, CM-specific ADGRG1 deletion accelerates cardiac dysfunction, concurrent with blunted CM hypertrophy, enhanced cardiac inflammation and increased mortality, suggesting that ADGRG1 plays an important role in the early adaptation to chronic cardiac stress. Altogether, the present study provides an important proof-of-concept that targeting CM-expressed AGPCRs may offer a new avenue for regulating the development of heart failure.

Coupling antitoxins and blue/white screening with parAB/resolvase mutation as a strategy for Salmonella spp. plasmid curing.

Plasmids play an important role in bacterial physiology, adaptation, evolution, virulence, and antibiotic resistance. An in-depth study of these roles partly depends on the generation of plasmid-free cells. This study shows that vector tools that target genes required for plasmid stability in the presence of an antitoxin-expressing helper plasmid are a viable approach to cure specific plasmids. Expression of bgaB from target plasmids can greatly facilitate visual detection of plasmid cured colonies avoiding time-consuming screening procedures. This approach can be refined for the development of a universal plasmid curing system that can be used to generate plasmid-free cells in other human bacterial pathogens including Gram positives and Gram negatives.

Supply chain agility in humanitarian organisations: examining the role of self-organisation, information integration and adaptability in South Sudan

PurposeThe purpose of this paper is to propose and validate a theoretical model to investigate the relationship between self-organisation, information integration, adaptability and supply chain agility in humanitarian organisations.Design/methodology/approachA theoretical model was developed from extant studies and assessed through a structured questionnaire survey of 86 humanitarian organisations operating in South Sudan. The data were analysed using partial least square structural equation modelling.FindingsThe study found that self-organisation has a discernible positive influence on supply chain agility not only directly but also indirectly through adaptability. Further, information integration does not significantly influence supply chain agility directly but is fully mediated by adaptability. Together, the antecedent variables account for 53.9% variance in supply chain agility.Research limitations/implicationsThis study contributes to providing an empirical understanding of a humanitarian supply chain as a complex adaptive system and hence the need to incorporate self-organising and adaptive dimensions in supply chain management practice. Furthermore, it confirms the centrality of the complex adaptive system feature of adaptability when building supply chain agility through self-organisation and information integration.Practical implicationsThe findings provide a firm ground for managerial decisions on investment in self-organisation and information integration dimensions so as to enhance adaptability and improve supply chain agility in humanitarian organisations.Originality/valueThis study is distinctive in the sense that it uses the complex adaptive system variables to empirically validate the relationships between self-organisation, information integration, adaptability and supply chain agility in humanitarian organisations in the world’s youngest developing economy with a long history of conflict and humanitarian intervention. The mediating influence of adaptability examined in this study is also novel.

A negative feedback regulatory module comprising R3-MYB repressor MYBL2 and R2R3-MYB activator PAP1 fine-tunes high light-induced anthocyanin biosynthesis in Arabidopsis

Abstract Anthocyanins, a group of flavonoids, play diverse roles in plant growth and environmental adaptation. The biosynthesis and accumulation of anthocyanin are regulated by environmental cues, such as high light. However, the precise mechanism underlying anthocyanin biosynthesis under high light conditions remains largely unclear. Here, we report that the R3-MYB repressor MYB-LIKE 2 (MYBL2) negatively regulates high light-induced anthocyanin biosynthesis by repressing two R2R3-MYB activators, PRODUCTION OF ANTHOCYANIN PIGMENT 1 (PAP1) and PAP2, which are core components of the MYB-bHLH-WD40 (MBW) complex. We found that MYBL2 interacts with PAP1/2 and reduces their transcriptional activation activities, thus disrupting the expression of key genes involved in anthocyanin biosynthesis, such as DIHYDROFLAVONOL 4-REDUCTASE (DFR) and TRANSPARENT TESTA 19 (TT19). Additionally, MYBL2 attenuates the transcriptional activation of PAP1 on its own expression, but not PAP2. Conversely, PAP1 collaborates with TT8, a bHLH member of the MBW complex, to activate MYBL2 transcription when excessive anthocyanins are accumulated. Taken together, our findings reveal a negative feedback regulatory module composed of MYBL2 and PAP1 that fine-tunes high light-induced anthocyanin biosynthesis through modulating MBW complex assembly.