Rapid Adaptation Research Articles

Selenium alters the gene content but not the taxonomic composition of the soil microbiome

Abstract Background Microbiomes, essential to ecosystem processes, face strong selective forces that can drive rapid evolutionary adaptation. However, our understanding of evolutionary processes within natural systems remains limited. We investigated evolution in response to naturally occurring selenium in soils of different geological parental materials on the Western Slope of Colorado. Our study focused on examining changes in gene frequencies within microbial communities in response to selenium exposure. Results Despite expectations of taxonomic composition shifts and increased gene content changes at high-selenium sites, we found no significant alterations in microbial diversity or community composition. Surprisingly, we observed a significant increase in differentially abundant genes within high-selenium sites. Conclusions These findings are suggestive that selection within microbiomes primarily drives the accumulation of genes among existing microbial taxa, rather than microbial species turnover, in response to strong stressors like selenium. Our study highlights an unusual system that allows us to examine evolution in response to the same stressor annually in a non-model system, contributing to understanding microbiome evolution beyond model systems.

Genome-Wide Identification of GRAS Gene Family in Cunninghamia lanceolata and Expression Pattern Analysis of ClDELLA Protein Under Abiotic Stresses

The Chinese fir (Cunninghamia lanceolata) is a significant species utilized in afforestation efforts in southern China. It is distinguished by its rapid growth and adaptability to diverse environmental conditions. The GRAS gene family comprises a group of plant-specific transcription factors that play a pivotal role in plant growth and development, response to adversity, and hormone regulatory networks. However, the exploration of the GRAS family in gymnosperm Chinese fir has not yet begun. In this study, a total of 43 GRAS genes were identified in the whole genome of Chinese fir, and a phylogenetic analysis classified them into nine distinct subfamilies. Gene structure analysis revealed that the majority of ClGRAS genes lacked introns. It is notable that among these proteins, both ClGAI and ClGRA possess distinctive DELLA structural domains. Cis-acting element analysis revealed that nearly all ClGRAS genes contained light-responsive elements, while hormone-responsive elements, environmental-responsive elements (low-temperature- or defense-responsive elements), and meristem-organization-related elements were also identified. Based on transcriptome data and RT-qPCR expression patterns, we analyzed the expression of ClGAI and ClRGA genes across different developmental stages, hormones, and three abiotic stresses. Subcellular localization analysis demonstrated that ClGAI and ClRGA were localized to the nucleus. Transcriptional activation assays showed that both genes have self-activating activity. In conclusion, the results of this study indicate that the ClGRAS gene family is involved in the response of Chinese fir to environmental stress. Further research on the ClDELLA genes provides valuable information for exploring the potential regulatory network of DELLA proteins in Chinese fir.

Large Scale Ultrafast Manufacturing of Wireless Soft Bioelectronics Enabled by Autonomous Robot Arm Printing Assisted by a Computer Vision-Enabled Guidance System for Personalized Wound Healing.

A Customized wound patch for Advanced tissue Regeneration with Electric field (CARE), featuring an autonomous robot arm printing system guided by a computer vision-enabled guidance system for fast image recognition is introduced. CARE addresses the growing demand for flexible, stretchable, and wireless adhesive bioelectronics tailored for electrotherapy, which is suitable for rapid adaptation to individual patients and practical implementation in a comfortable design. The visual guidance system integrating a 6-axis robot arm enables scans from multiple angles to provide a 3D map of complex and curved wounds. The size of electrodes and the geometries of power-receiving coil are essential components of the CARE and are determined by a MATLAB simulation, ensuring efficient wireless power transfer. Three heterogeneous inks possessing different rheological behaviors can be extruded and printed sequentially on the flexible substrates, supporting fast manufacturing of large customized bioelectronic patches. CARE can stimulate wounds up to 10 mm in depth with an electric field strength of 88.8 mVmm-1. In vitro studies reveal the ability to accelerate cell migration by a factor of 1.6 and 1.9 for human dermal fibroblasts and human umbilical vein endothelial cells, respectively. This study highlights the potential of CARE as a clinical wound therapy method to accelerate healing.

OGC SO04 - Impact of COVID-19 on Decision-making and Survival in Esophago-Gastric Cancer Treatment: Insights from a Multidisciplinary Approach

Abstract Background The COVID-19 pandemic necessitated rapid adaptation in healthcare delivery, affecting cancer care pathways. This study assesses the impact of these changes on multidisciplinary team (MDT) decision-making and survival outcomes in esophago-gastric cancer patients across pre-pandemic, peak pandemic, and post-pandemic periods. Method A retrospective cohort study involving patients referred to a UK tertiary EG cancer center during distinct six-month intervals mirroring the pandemic's evolution. Analysis focused on MDT recommendations, treatment pathways, and two-year survival rates, comparing deviations from standard care across periods. Results The study revealed a significant reduction in patient referrals and expedited treatment decisions during the pandemic peak, with a shift towards palliative care in post-pandemic cases. Although no statistically significant difference in two-year survival rates was observed, the post-pandemic period showed an increase in tumor aggressiveness and positive resection margins, suggesting potential long-term impacts of delayed diagnosis and treatment. Conclusion COVID-19 has significantly influenced MDT decision-making and patient pathways in esophago-gastric cancer care, underlining the necessity of resilient healthcare systems. Despite maintaining survival rates, the observed increase in tumor aggressiveness post-pandemic highlights the critical need for uninterrupted cancer diagnosis and treatment services during global health emergencies.

Rapid sensorimotor adaptation to auditory midbrain silencing in free-flying bats.

Echolocating bats rely on rapid processing of auditory information to guide moment-to-moment decisions related to echolocation call design and flight path selection. The fidelity of sonar echoes, however, can be disrupted in natural settings due to occlusions, noise, and conspecific jamming signals. Behavioral sensorimotor adaptation to external blocks of relevant cues has been studied extensively, but little is known about adaptations that mitigate internal sensory flow interruption. How do bats modify their sensory-guided behaviors in natural tasks when central auditory processing is interrupted? Here, we induced internal sensory interruptions by reversibly inactivating excitatory neurons in the inferior colliculus (IC) using ligand-activated inhibitory designer receptors exclusively activated by designer drugs (DREADDs). Bats were trained to navigate through one of three open windows in a curtain to obtain a food reward, while their echolocation and flight behaviors were quantified with synchronized ultrasound microphone and stereo video recordings. Under control conditions, bats reliably steered through the open window, only occasionally contacting the curtain edge. Suppressing IC excitatory activity elevated hearing thresholds, disrupted overall performance in the task, increased the frequency of curtain contact, and led to striking compensatory sensorimotor adjustments. DREADDs-treated bats modified flight trajectories to maximize returning echo information and adjusted sonar call design to boost detection of obstacles. Sensorimotor adaptations appeared immediately and did not change over successive trials, suggesting that these behavioral adaptations are mediated through existing neural circuitry. Our findings highlight the remarkable rapid adaptive strategies bats employ to compensate for internal sensory interruptions to effectively navigate their environments.

Successful Invasion Into New Environments Without Evidence of Rapid Adaptation by a Predatory Marine Gastropod.

Invasive species with native ranges spanning strong environmental gradients are well suited for examining the roles of selection and population history in rapid adaptation to new habitats, providing insight into potential evolutionary responses to climate change. The Atlantic oyster drill (Urosalpinx cinerea) is a marine snail whose native range spans the strongest coastal latitudinal temperature gradient in the world, with invasive populations established on the US Pacific coast. Here, we leverage this system using genome-wide SNPs and environmental data to examine invasion history and identify genotype-environment associations indicative of local adaptation across the native range, and then assess evidence for allelic frequency shifts that would signal rapid adaptation within invasive populations. We demonstrate strong genetic structuring among native regions which aligns with life history expectations, identifying southern New England as the source of invasive populations. Then, we identify putatively thermally adaptive loci across the native range but find no evidence of allele frequency shifts in invasive populations that suggest rapid adaptation to new environments. Our results indicate that while these loci may underpin local thermal adaptation in their native range, selection is relaxed in invasive populations, perhaps due to complex polygenic architecture underlying thermal traits and/or standing capacity for phenotypic plasticity. Given the prolific invasion of Urosalpinx, our study suggests population success in new environments is influenced by factors other than selection on standing genetic variation that underlies local adaptation in the native range and highlights the importance of considering population history and environmental selection pressures when evaluating adaptive capacity.

Dual Control Strategy for Non-Minimum Phase Behavior Mitigation in DC-DC Boost Converters Using Finite Control Set Model Predictive Control and Proportional–Integral Controllers

Model Predictive Control (MPC) has emerged as a promising alternative for controlling power converters, offering benefits such as flexibility, simplicity, and rapid control response, particularly when short-horizon algorithms are employed. This paper introduces a system using a short-horizon Finite Control Set MPC (FCS-MPC) strategy to specifically address the challenge of non-minimum phase behavior in boost converters. The non-minimum phase issue, which complicates the control process by introducing an initial inverse response, is effectively mitigated by the proposed method. A Proportional–Integral (PI) controller is integrated to dynamically adjust the reference current based on the output voltage error, thereby enhancing overall system stability and performance. Unlike conventional PI-MPC methods, where the PI controller has an influence on the system dynamics, the PI controller in this approach is solely used for tuning the reference current needed for the FCS-MPC controller. The PI controller addresses small deviations in output voltage, primarily due to model prediction inaccuracies, ensuring steady-state accuracy, while the FCS-MPC handles fast dynamic responses to adapt the controller’s behavior based on load conditions. This dual control strategy effectively balances the need for precise voltage regulation and rapid adaptation to varying load conditions. The proposed method’s effectiveness is validated through a multi-stage simulation test, demonstrating significant improvements in response time and stability compared to traditional control methods. Hardware-in-the-loop testing further confirms the system’s robustness and potential for real-time applications in power electronics.

Formation of an effective mechanism of innovation management at enterprises

The article examines the importance of the formation of an effective mechanism of innovative management in the conditions of the modern global economy and the state of war. Attention is focused on the essence of innovation management, its main tasks and elements, such as strategy, organizational structure, innovation processes, innovation culture, knowledge management and financing. The problems and challenges that arise during the implementation of innovative management in the conditions of war are highlighted separately, in particular, the need to adapt strategies to the changing environment and resource limitations. The prospects for the development of innovative mechanisms in the context of digital technologies and artificial intelligence, which can contribute to rapid adaptation to new conditions, are also considered. The article emphasizes that an effective innovation mechanism is the key to achieving high results and competitiveness of organizations even in difficult conditions.

Asymmetric genome merging leads to gene expression novelty through nucleo-cytoplasmic disruptions and transcriptomic shock in Chlamydomonas triploids.

Genome merging is a common phenomenon causing a wide range of consequences on phenotype, adaptation, and gene expression, yet its broader implications are not well-understood. Two consequences of genome merging on gene expression remain particularly poorly understood: dosage effects and evolution of expression. We employed Chlamydomonas reinhardtii as a model to investigate the effects of asymmetric genome merging by crossing a diploid with a haploid strain to create a novel triploid line. Five independent clonal lineages derived from this triploid line were evolved for 425 asexual generations in a laboratory natural selection experiment. Utilizing fitness assays, flow cytometry, and RNA-Seq, we assessed the immediate consequences of genome merging and subsequent evolution. Our findings reveal substantial alterations in genome size, gene expression, protein homeostasis, and cytonuclear stoichiometry. Gene expression exhibited expression-level dominance and transgressivity (i.e. expression level higher or lower than either parent). Ongoing expression-level dominance and a pattern of 'functional dominance' from the haploid parent was observed. Despite major genomic and nucleo-cytoplasmic disruptions, enhanced fitness was detected in the triploid strain. By comparing gene expression across generations, our results indicate that proteostasis restoration is a critical component of rapid adaptation following genome merging in Chlamydomonas reinhardtii and possibly other systems.

091. Impact of the Covid-19 Pandemic on Breast Cancer Surgery Care in 8 Institutiona Around Southeast and South Asia

Background: The COVID-19 pandemic brought about unprecedented disruptions to surgical services globally, which could have led to delays in surgical care for breast cancer patients. This study analysed the institutional responses of tertiary hospitals from selected Asian countries to the COVID-19 pandemic. Methods: We identified all patients newly diagnosed with breast cancer from 16 institutions (9 countries: Singapore, Bangladesh, India, Indonesia, Malaysia, Pakistan, Philippines, Sri Lanka and Vietnam) from 11 Mar 2020 to 10 Mar 2021 (“covid”) and compared them to those diagnosed 11 Mar 2019 to 10 Mar 2020 (“precovid”). The following data were collected and retrospectively analysed: number of breast cancer surgeries and timeliness of surgery (days from diagnosis to surgery); type of surgery (breast conserving surgery [BCS], mastectomy without [Ms] and with reconstruction [MRecon]), and clinical stage at diagnosis. Results: 4816 patients (2550 in “precovid” and 2266 in “covid” cohort) were included. Median age at diagnosis was 57 for both cohorts (r, 20-117) (p=0.79). In overall number of cases (n=4877), there is no statistically significant difference between pre- (n=2515, 51.6%) v. covid (n=2362, 48.4%) period (p=0.26). Sequence of treatments was similar in both cohorts (upfront surgery [n=3983 cases, 53.7% v. 46.3%, p=0.08; or surgery after neoadjuvant therapy [n=878 cases, 48.9% v. 51.1%, p=0.79]). Five of 16 institutions experienced a decrease in number of surgeries (p<0.05) during the first year of the pandemic, and across all 3 types of surgery, while 1 institution received more cases (p=0.002). Two other institutions had statistically significant more patients with neoadjuvant therapy (p=0.003 and p<0.001) and 1 of these two showed an increase in BCS (p=0.04) and MRecon (p=0.04) cases during covid compared to the precovid period. Five of 12 institutions had significantly longer waiting time from diagnosis to surgery (p<0.05). Trend analysis per quartile during covid period demonstrated that number of surgeries and timeliness dipped mainly in the first quartile, followed by rapid rebound in surgeries across all institutions in the next 2 quartiles. There was no difference in clinical stage at presentation in the 2 time periods. Conclusion: The COVID-19 pandemic initially impacted the number of breast cancer surgeries performed by institutions in Asia. This was followed by rapid adaptation and restoration of surgical services by institutions.

ОСОБЛИВОСТІ ВНУТРІШНЬОГО КОНТРОЛЮ РОЗРАХУНКІВ ПІДПРИЄМСТВА В УМОВАХ ВОЄННОГО СТАНУ

Introduction. In the conditions of martial law, enterprises face new challenges that affect all areas of their economic activity, including settlement operations. Internal control of settlements becomes critical for ensuring financial stability and supporting operational activities. This requires a study of the specifics of the organization of internal control of the company's calculations during the state of war, in particular the issue of ensuring the security of financial operations in conditions of instability and market uncertainty. The purpose of the article. The purpose of the study is to investigate the features and effective mechanisms of internal control of payments at enterprises operating under martial law to ensure their financial stability and competitiveness. Methods. The research methodology includes a comprehensive approach that combines general scientific methods: analysis, synthesis, comparison, as well as specific financial and economic methods of evaluating the internal control system, including methods of risk analysis and auditing of financial operations. Results. The article examines the main principles of ensuring effective internal control of the calculations of economic entities in the conditions of martial law. It was found that failures in the work of banking systems, interruptions in communications and logistics significantly complicate the timely execution of financial transactions. The need to strengthen control over payment discipline on the part of both the enterprise and its counterparties has been identified. The necessity of implementing additional measures to protect the payment system, including increased attention to the verification of counterparties and the use of digital monitoring tools, has been proven. The growing need for rapid adaptation of internal control procedures to new conditions, such as changes in legislation introduced in connection with military operations, or new requirements for financial reporting, which requires the involvement of qualified personnel capable of promptly responding to new challenges and risks, has been studied. Conclusions. It has been proven that the internal control of the company's calculations in the conditions of martial law is an important element of maintaining stable operations and financial security. Therefore, to ensure its effectiveness, it is necessary to constantly update control methods, take into account new risks and challenges associated with war, and implement modern monitoring tools on the basis.

Microbiome transfer from native to invasive species may increase invasion risk.

In a fast-changing world, understanding how organisms adapt to their environment is a pressing necessity. Research has focused on genetic adaptation, while our understanding of non-genetic modes is still in its infancy. The host-associated microbiome can be considered a non-genetic mode of adaptation, which can strongly influence an organism's ability to cope with its environment. However, the role of the microbiome in host ecological dynamics is largely unexplored, particularly in animal communities. Here, we discuss the following hypothesis: invasive species may rapidly adapt to local conditions by adopting beneficial microbes from similar co-occurring native species. This occurs when the invader's fitness is influenced by adaptation to local conditions that is facilitated by microbes acquired from native microbiomes. We present a minimal mathematical model to explore this hypothesis and show that a delayed acquisition of native microbes may explain the occurrence of an invasion lag. Overall, our results contribute to broadening the conceptualization of rapid adaptation via microbiome transfer and offer insights towards designing early intervention strategies for invasive species management.

Pediatric Learning Health Networks in Solid Organ Transplantation-Engaging all Stakeholders to Achieve Health for Children Who Require Transplantation.

Learning Health Networks (LHN) have evolved within medicine over the past two decades, but their integration into transplantation has been more recent. In this paper, we describe three LHNs in end-stage organ disease/transplantation, their common and unique features, and how their "actor-oriented" architecture allowed for rapid adaptation to meet the needs of their patients and practitioners during the recent COVID-19 pandemic. The structure and focus of the Improving Renal Outcomes Collaborative (IROC), Starzl Network for Excellence in Pediatric Transplantation (SNEPT), and the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) are reviewed. We discuss the critical role of patient and family engagement, focusing on collaboration with Transplant Families. Finally, we review challenges common to the LHN concept and potential common areas of alignment to achieve the goal of more rapid and sustained progress to improve health in pediatric transplantation. LHN in transplantation are essential to accelerate knowledge dissemination and improve outcomes.

Happy new ears: rapid adaptation to novel spectral cues in vertical sound localization.

Happy new ears: rapid adaptation to novel spectral cues in vertical sound localization.

Dephosphorylation of bZIP59 by PP2A ensures appropriate shade avoidance response in Arabidopsis.

Changes in light quality and quantity experienced by many shade-intolerant plants grown in close proximity lead to transcriptional reprogramming and shade avoidance syndrome (SAS). Despite the importance of phosphorylation-dependent signaling in cellular physiology, phosphorylation events during SAS are largely unknown. Here, we examined shade-regulated phosphorylation events in Arabidopsis using quantitative phosphoproteomics. We confirmed shade-induced dephosphorylation of bZIP59, a basic region/leucine zipper motif (bZIP) transcription factor. Shade treatment promotes the nuclear localization of bZIP59, which can be mimicked by mutation of the phosphorylation sites on bZIP59. Phenotypic analysis identified that bZIP59 negatively regulated shade-induced hypocotyl elongation. bZIP59 repressed the shade-induced activation of certain growth-related genes, while shade increased the DNA binding of bZIP59. Furthermore, the protein phosphatase 2A (PP2A) mediated dephosphorylation of bZIP59. Our study characterized a previously unidentified mechanism by which the phytochrome B (phyB)-PP2A-bZIP59 regulatory module integrates shade signals and transcriptomes, broadening our knowledge of phosphorylation strategies for rapid adaptation to shade.

The Interior Contact-Aided Rolling Element

Abstract This work introduces an interior contact-aided rolling element (I-CORE) compliant mechanism that draws upon the concepts used for the contact-aided rolling element, cross-axis flexural pivot, and pre-curved flexible beam. The I-CORE incorporates a bilinear compressive stiffness response with an initial tailorable stiffness governed by the flexural geometry, followed by a stiffness curve governed by the material stiffness at the contact point. The I-CORE mechanism can achieve one or two degrees of rotational freedom as well as a single degree of translational freedom. The purpose of the present work was to introduce the I-CORE mechanism, as well as a pseudo-rigid-body replacement model (PRBM) of the I-CORE mechanism which was subsequently validated using both finite element analysis and benchtop mechanical testing. A pseudo-rigid body model was created for the I-CORE to simplify the rapid adaptation of this mechanism to different design applications. This model was validated using both finite element analysis and benchtop mechanical testing under both compression and rotation loading conditions. Additionally, multiple configurations of the device were created and evaluated in order to test its sensitivity to certain design features including the flexure width, flexure thickness, and the radius of the rounded contact surfaces. It was found that the model is sensitive to the thickness of the flexures and that despite some limitations, the pseudo-rigid body model is sufficiently accurate for initial design work. Some possible applications of the mechanism are proposed.

Venetoclax dose escalation rapidly activates a BAFF/BCL-2 survival axis in chronic lymphocytic leukemia

AbstractVenetoclax, a first-in-class BH3 mimetic drug that targets BCL-2, has improved the outcomes of patients with chronic lymphocytic leukemia (CLL). Early measurements of the depth of the venetoclax treatment response, assessed by minimal residual disease, are strong predictors of long-term clinical outcomes. However, there are limited data on the early changes induced by venetoclax treatment that might inform strategies to improve responses. To address this gap, we conducted longitudinal mass cytometric profiling of blood cells from patients with CLL during the first 5 weeks of venetoclax monotherapy. At baseline, we resolved CLL heterogeneity at the single-cell level to define multiple subpopulations in all patients based on proliferative, metabolic, and cell survival proteins. Venetoclax induced a significant reduction in all CLL subpopulations and caused rapid upregulation of the prosurvival BCL-2, BCL-XL, and mantle cell lymphoma-1 proteins in surviving cells, which had reduced sensitivity to the drug. In mouse models, the venetoclax-induced elevation of survival proteins in B cells and CLL-like cells that persisted was recapitulated, and genetic models demonstrated that extensive apoptosis and access to the B cell cytokine, B cell activating factor (BAFF), were essential. Accordingly, in patients with CLL who were treated with venetoclax or the anti-CD20 antibody obinutuzumab there was marked elevation in BAFF and an increase in prosurvival proteins in leukemic cells that persisted. Overall, these data highlight the rapid adaptation of CLL cells to targeted therapies through homeostatic factors and support cotargeting of cytokine signals to achieve deeper and more durable long-term responses.

Enhancing the Understanding of Abdominal Trauma During the COVID-19 Pandemic Through Co-Occurrence Analysis and Machine Learning.

This study examines the impact of the COVID-19 pandemic on abdominal trauma management by comparing pre-pandemic (17 February 2018-26 February 2020) and pandemic periods (27 February 2020-7 March 2022). Analyzing data from 118 patients at the Emergency County Clinical Hospital of Craiova, we identified significant shifts in clinical practices affecting patient outcomes. During the pandemic, a moderate increase in surgical interventions for specific abdominal traumas indicated the effective adaptation of the medical system. Prioritizing critical cases and deferring non-urgent procedures optimized limited resources. Demographic and clinical factors-including age, sex, body mass index (BMI), and red cell distribution width (RDW)-significantly influenced the hospitalization duration and recovery outcomes. Gender disparities in mortality lessened during the pandemic, possibly due to standardized interventions and the physiological effects of SARS-CoV-2. The link between occupation and obesity highlighted how work environments impact trauma severity, especially as lifestyle changes affect BMI. While age remained a major predictor of mortality, its influence slightly decreased, potentially due to improved protocols for elderly patients. RDW emerged as an important prognostic marker for disease severity and mortality risk. Employing advanced co-occurrence analysis enhanced with machine learning, we uncovered complex relationships between clinical and demographic variables often overlooked by traditional methods. This innovative approach provided deeper insights into the collective impact of various factors on patient outcomes. Our findings demonstrate the healthcare system's rapid adaptations during the pandemic and offer critical insights for optimizing medical strategies and developing personalized interventions in global crises.

Kinematic matrix: One-shot human action recognition using kinematic data structure

One-shot action recognition, which refers to recognizing human-performed actions using only a single training example, holds significant promise in advancing video analysis, particularly in domains requiring rapid adaptation to new actions. However, existing algorithms for one-shot action recognition face multiple challenges, including high computational complexity, limited accuracy, and difficulties in generalization to unseen actions. To address these issues, we propose a novel kinematic-based skeleton representation that effectively reduces computational demands while enhancing recognition performance. This representation leverages skeleton locations, velocities, and accelerations to formulate the one-shot action recognition task as a metric learning problem, where a model projects kinematic data into an embedding space. In this space, actions are distinguished based on Euclidean distances, facilitating efficient nearest-neighbour searches among activity reference samples. Our approach not only reduces computational complexity but also achieves higher accuracy and better generalization compared to existing methods. Specifically, our model achieved a validation accuracy of 78.5%, outperforming state-of-the-art methods by 8.66% under comparable training conditions. These findings underscore the potential of our method for practical applications in real-time action recognition systems.

Transcriptomic Response of Rhizobium leguminosarum to Acidic Stress and Nutrient Limitation Is Versatile and Substantially Influenced by Extrachromosomal Gene Pool.

Multipartite genomes are thought to confer evolutionary advantages to bacteria by providing greater metabolic flexibility in fluctuating environments and enabling rapid adaptation to new ecological niches and stress conditions. This genome architecture is commonly found in plant symbionts, including nitrogen-fixing rhizobia, such as Rhizobium leguminosarum bv. trifolii TA1 (RtTA1), whose genome comprises a chromosome and four extrachromosomal replicons (ECRs). In this study, the transcriptomic responses of RtTA1 to partial nutrient limitation and low acidic pH were analyzed using high-throughput RNA sequencing. RtTA1 growth under these conditions resulted in the differential expression of 1035 to 1700 genes (DEGs), which were assigned to functional categories primarily related to amino acid and carbohydrate metabolism, ribosome and cell envelope biogenesis, signal transduction, and transcription. These results highlight the complexity of the bacterial response to stress. Notably, the distribution of DEGs among the replicons indicated that ECRs played a significant role in the stress response. The transcriptomic data align with the Rhizobium pangenome analysis, which revealed an over-representation of functional categories related to transport, metabolism, and regulatory functions on ECRs. These findings confirm that ECRs contribute substantially to the ability of rhizobia to adapt to challenging environmental conditions.