Journal of Microbiology & Biology Education
● American Society for Microbiology
Preprints posted in the last 30 days, ranked by how well they match Journal of Microbiology & Biology Education's content profile, based on 11 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Otto, J. L.; Goulet, L.; Kopack Ware, B.; Lowry, H.; Miller, A.-E.; Botello, J. D.; Pruett, J. E.; Beatty, A. E.
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Evolution is a foundational framework for understanding biology, yet it remains challenging to teach and learn. Game-based learning may offer one way to support evolution instruction by helping students visualize abstract, dynamic, and difficult-to-observe processes. In this study, we interviewed undergraduate biology instructors to examine how they evaluated video games as potential tools for evolution education, including which topics they perceived as most challenging for students. We found that instructors were broadly open to using video games for evolution instruction, particularly when games could support population-level reasoning, evolutionary mechanisms, speciation and phylogeny, quantitative reasoning, and long time scales. Instructors also emphasized that games must be scientifically accurate, accessible, and aligned with course learning goals. This study contributes an instructor-centered perspective to evolution education and game-based learning research by identifying how instructors connect persistent student learning challenges with potential design priorities for educational video games. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/736808v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@175ce4corg.highwire.dtl.DTLVardef@13ae260org.highwire.dtl.DTLVardef@e44aceorg.highwire.dtl.DTLVardef@1eb1ef1_HPS_FORMAT_FIGEXP M_FIG C_FIG
Nasik, B.; Nifoussi, S.
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Effective group work is central to Problem-Based Learning (PBL) in higher education, yet the optimal strategy for forming student groups remains unclear. This study compared MBTI based grouping, informed by personality types and Keirsey temperaments, with Learning Style Based (LSB) grouping, grounded in Kolbs Experiential Learning Theory, to assess their impact on group functioning and role performance. Participants were undergraduate students enrolled in Cell Biology (Fall 2022 and Fall 2023) and Introduction to Biology Laboratory (Fall 2023) courses. Students completed MBTI and Kolb Learning Style assessments, and groups and roles (Leader, Communicator, Organizer) were assigned accordingly. Results indicated that LSB-based groups consistently outperformed MBTI-based groups across multiple performance metrics, including productivity, listening, sense of safety, belonging, and overall satisfaction. All metrics showed statistically significant decreases in MBTI based groups except contribution, which did not differ significantly between grouping strategies. Role performance ratings were significantly higher for Leaders and Communicators in LSB groups, while no significant differences were observed for the Organizer role. Correlation analyses revealed that satisfaction was strongly associated with perceived productivity in MBTI based groups, whereas in LSB based groups, satisfaction was more strongly correlated with psychological safety. These findings suggest that learning style alignment may better support effective collaboration and group climate in PBL settings than personality based grouping.
Russo-Tait, T.; Nichols, H. M.; Swanson, T. C.
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Racial equity remains a critical challenge in postsecondary science education, as Black students experience higher attrition rates and diminished well-being compared to their White peers. While active learning has been shown to reduce failure rates and narrow achievement gaps, the interpersonal affordances and constraints of peer discussions within these settings remain underexplored for Black students. Grounded in Critical Race Theory and utilizing the analytical lenses of racial microaggressions, microaffirmations, and Community Cultural Wealth, this study addresses this issue by investigating the racialized interpersonal experiences of Black students in active learning college science classrooms. Through semi-structured interviews, this study explores the nature of both exclusionary and affirming peer interactions and how students navigate these dynamics. Findings reveal that Black students frequently encounter racialized microaggressions--manifestations of macro-level anti-Blackness-- in the classroom which contribute to isolation and racial battle fatigue. Conversely, students describe instances of microaffirmations, predominantly through small counterspaces created by and for other students of color, which validate their intellectual contributions and foster a sense of belonging. Despite facing these tensions, participants advocate for active learning as a beneficial practice, provided that instructors implement explicit, equitable structures and facilitate culturally responsive classroom climates. These findings offer actionable implications for researchers and practitioners to design more inclusive active learning environments by explicitly addressing interpersonal dynamics, promoting cultural competence, and co-constructing humanizing science classroom climates.
Gray, S. J.; Taylor, K.; Shumaker, K. A.; Bochman, M. L.
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Course-based undergraduate research experiences (CUREs) are widely recognized as a high-impact practice in biology education, yet most existing CURE frameworks treat the research organism as an interchangeable teaching prop rather than a genuine scientific contribution. We argue that place-based, community-embedded CUREs - in which students isolate, characterize, and publicly deploy a locally meaningful wild organism - constitute a qualitatively distinct model warranting broader adoption. As proof of concept, we present the Declaration of Fermentation project at Indiana University Bloomington: graduate researchers isolated a wild Saccharomyces cerevisiae strain from the bark of a campus landmark tree, confirmed its wild provenance by whole-genome sequencing and phylogenomics, and partnered with local craft breweries to produce a colonial-era inspired ale released publicly for the 250th anniversary of the Declaration of Independence. Volunteer sensory panels at two independent public tasting events (combined n = 33-34 per attribute) confirmed a fruity-funky profile consistent with wild-strain fermentation, with no significant differences between events (Mann-Whitney U, Benjamini-Hochberg-corrected p > 0.05 for all 11 attributes). We describe three design principles - genomically confirmed strain identity, mandatory community partnership, and place-based historical narrative - that distinguish this model from prior wild yeast brewing CUREs, discuss how these principles generalize to other institutions and fermentation vehicles, and identify next steps for formal learning assessment. Complete implementation protocols are provided as supplemental Appendices 1-6, and the bioinformatics pipeline is freely available at https://doi.org/10.5281/zenodo.20679384.
Pradhan, S. M.; Chakravarty, A.; Hari, A.; Nampoothiri, V.; Rani, K.; Edathadathil, F.; Singh, S. K.
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Antimicrobial resistance (AMR) is a global threat to public health and development. Failure to address it could return society to a pre-antibiotic era with increased morbidity and mortality. Because human behaviour is crucial to AMR management, interventions modifying knowledge, attitudes, and practices are therefore essential. Modifying health-related behaviours presents a significant challenge, yet it is crucial for public health. Engaging populations during periods of shifting perceptions can address this challenge and ensure the sustainability of interventions. Adolescents and young people attending school represent a key demographic. The primary objective of this study is to evaluate student's awareness, perceptions, and behaviours concerning antimicrobial resistance (AMR) and hygiene, while enhancing and empowering children as agents of change within the community. In this study, students from Allied Health Sciences (AHS) across various disciplines were recruited to serve as peer educators for an evidence-informed educational workshop. A pilot delivery of these activities was conducted among a few students in a school before the final delivery was executed in three schools. Schools following a comparable educational board and curriculum were selected for inclusion in the study. A structured questionnaire was employed to assess the effects before and after the intervention. Statistically significant improvements were observed in participant's knowledge, attitudes, and practices (p < 0.001). Additionally, feedback was collected from participants, teachers, and the school nurse attending the session. By triangulating these findings, a notable immediate improvement was observed in students' knowledge, attitudes, and practices. This study provides evidence that employing multimodal teaching led by peer education is a valid and effective method for delivering health messages. It further underscores the mutual benefits for stakeholders (peer educators and peer learners) by offering a two-way learning opportunity. The benefits extend beyond academic and core scientific learning to include increased confidence as effective health educators and future-ready healthcare professionals.
Gao, Y.; Zhang, L.
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This study investigated how different forms of task influence the oral performance of Chinese second-language learners and native speakers. By analyzing data from 40 Chinese second-language learners and 40 native speakers through picture description tasks, formal and informal questions, and questions with different emotions (happy and unhappy), it was found that different task characteristics significantly affected language performance. Short picture tasks led to higher communication efficiency and noun rates but more errors, while long story tasks showed higher verb rates, function word rates, etc. Formal questions had more characters and nouns but lower communication efficiency compared to informal ones. Also, happy emotion questions resulted in fewer characters, sentences, and errors than unhappy emotion questions. These findings contribute to the theoretical understanding of task-based language performance in Chinese as a second language and offer practical implications for teaching, textbook compilation, and student evaluation.
Ring, B.; Hindmarch, C. C. T.; Archer, S. L.
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Background: Canadian biomedical core facilities (BCFs) provide researchers with access to advanced tools and unique technical expertise, essential for research. However, their role, sustainability, and impact remain poorly understood. We report on the evolution of model and existing state of Canadas 205 BCFs, examining challenges and benefits. Methods: Cross referencing of national databases by the Canadian Innovation Fund (CFI), and from data collected by the Canadian Network of Scientific Platforms (CNSP) allowed he identification of BCFs. Hand curation of these lists validated that cores are operational. To ensure cores not listed by CFI/CNSP were captured, research intensive institutions in Canada were independently searched to identify active cores. Results: There are currently 205 active and operational BCFs located across 9 provinces, which can be further stratified into 9 technical domains that describe the nature of services they provide. Quebec (80 cores) and Ontario (75 cores) have the highest confluence of BCFs, with Quebec having a higher ratio of cores per capita. Conclusions: While our data establishes the ubiquity of Canadian BCFs, we highlight substantial challenges including sustainability, governance, evaluation and the recognition of support for core scientists. Here, we establish a framework to address these challenges and to inform best practice, to optimize creation of impactful, accessible and functional biomedical core facilities.
Elson, J. L.; Venter, M.; Sinxadi, P.; Enos, J. Y.; Atobrah, D.; Mensah, G. I.; Pretorius, E.; Guthrie, S.; Pienaar, I. S.
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The focus was on leadership, mentoring and promotion. Using short, structured activities alongside small-group discussion, the participants were encouraged to reflect on leadership, mentoring and the perceived gap between being ready and being recognised for promotion. Descriptive survey findings and free-text reflections highlight the demand for structured peer support, reciprocal mentoring opportunities, and clearer, more transparent promotion processes. Following the event, we performed a structured review of the impact. This highlighted that the workshop participants reported that the event allowed for greater self-awareness into their own leadership approaches, a stronger commitment to purposeful mentoring, and greater confidence and renewed motivation to take concrete steps towards promotion.
Silva, J. C. F.; Vieira, A.; Chue Donahey, M. S.; Silva, S. M. d. C.; Veloso, T.; Lopes, A.; Sexson, N.; Barker, R.; Porterfield, D. M.; Silva, C. A.; Dias, R.
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Space biology literature is growing exponentially. Existing infrastructure has not kept pace with organizing, synthesizing, and disseminating this knowledge. We present SpaceBio SpaceBio Knowledge Hub (www.spacebio.space), an integrated digital ecosystem that combines artificial intelligence, real-time data integration, and open-access infrastructure to advance research, education, and collaboration in microgravity, space biology and space exploration. The platform applies AI-driven approaches including natural language processing, machine learning, and automated content generation to construct a semantic atlas of the field. The atlas reveals the hierarchical thematic organization underlying microgravity-induced biological responses, space mission infrastructure, planetary science, and astrobiology. As part of this effort, SpaceBio is moving toward the construction of a LiteratOmics framework for microgravity, and space biology a systematic, AI-enabled approach to mining, integrating, and structuring the primary literature generated by omics-driven spaceflight research, treating the scientific literature itself as a navigable data layer alongside genomic, transcriptomic, and proteomic datasets. Built on a scalable, cloud-based architecture with a user-centered interface, SpaceBio supports literature exploration, data integration, and knowledge discovery for researchers, educators, students, industry partners, and citizen scientists. The platform also functions as a community-building ecosystem. It integrates hands-on research initiatives, AI-generated educational content, pilot data science projects, and social responsibility programs that broaden participation without compromising scientific rigor. AI-enabled digital environments can transform fragmented literature into a navigable knowledge landscape. SpaceBio accelerates research productivity, strengthens STEM education, and supports the global space life sciences community as human space exploration enters in the most ambitious era.
Lee, K. F. A.; Asharaf, S. T.; Liang, L.; Lee, T. M. C.
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Cortisol, our stress hormone, exerts widespread influence on neural activity. However, its influence on the aperiodic component of the electroencephalography power spectrum remains to be investigated. Given individual differences in the capacity to cope with stress and adversity, it also remains unclear whether trait resilience moderates this relationship. Hence, the present study examined whether individual differences in trait resilience moderates the association between resting cortisol and aperiodic activity. Participants (N=145) completed various self-report questionnaires (e.g., trait resilience). Electroencephalography was recorded over a 20-minute baseline period, followed by salivary cortisol collection. The results revealed a significant moderating effect of trait resilience in the occipital scalp region. Specifically, higher cortisol concentration was associated with flatter 1/f slopes amongst individuals with low trait resilience, whereas this association was reversed amongst those with high trait resilience. Overall, our findings highlight the role of individual differences in trait resilience in shaping hypothalamic-pituitary-adrenal axis-related neural dynamics.
Qiu, Z.; Wang, M.; Lu, H.; Abir, Y.; Zharmakhan, R.; Singh, N.; Poppe, M.; Degni, L.; Huys, Q. J.
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Serotonin and dopamine make dissociable contributions to reinforcement learning (RL) sub-components, yet we lack neural biomarkers capable of detecting their differential effects. Here, we report the development of a five-task EEG battery designed to probe these dissociable RL mechanisms. Using a model-free analytical approach in healthy volunteers, we identify distinct neural markers across probabilistic instrumental learning, motivational vigour, Pavlovian-instrumental transfer, reversal learning, and a working memory-RL task. A centro-parietal P300 tracked incremental learning across three paradigms and showed cross-task convergent validity. Readiness potentials and beta suppression indexed value-based motor preparation, while frontal theta captured Pavlovian-instrumental conflict. The largely independent pattern across markers supports the battery's capacity to detect selective pharmacological effects on distinct neural systems.
Chinnarasu, S.; Anozie, U.; Zhu, L.; Stafford, J. M.
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Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD) and associated dyslipidemia is a growing health issue that gives rise to cardiovascular risk. Men are more prone to development of MASLD than women. Understanding mechanisms underlying sex differences in MASLD may lead to improved prevention and treatment approaches. Cholesteryl ester transfer protein (CETP) is a lipid transfer protein that shuttles triglycerides and cholesteryl esters between blood lipoproteins and tissues. In this study investigate the impact of hepatic CETP expression on MASLD. Hepatic CETP expression (L-HuCETP) was achieved by injecting liver-targeted CETP-expressing adeno-associated virus into C57BL/6J mice. In females, L-HuCETP improved glucose tolerance, consistent with our prior clamp results in global human CETP transgenic mice. Whereas in males, L-HuCETP worsened glucose metabolism and impaired insulin signaling. Correspondingly, L-HuCETP expression reduced the expression of gluconeogenic pathway genes in females but upregulated these genes in males. In males, L-HuCETP mice exhibited increased hepatic lipid droplet accumulation, lipogenesis proteins and these changes were not observed in females. L-HuCETP expression resulted in sex-specific hepatic responses, with increased expression of inflammation and fibrosis related genes in male, but decreased expression of these genes in females. Mechanistic studies indicate that L-HuCETP had sex specific effects on transcription factors ChREBP and HNF4, which are important for glucose and lipid metabolism. Our studies suggest that sex-specific roles of L-HuCETP with regard to liver metabolic adaptation and MASLD risk in obesity, highlighting CETP-mediated pathways as potential targets for sex-specific precision medicine approaches to improve MASLD.
Franklin, S.; Dimitriou, M.; Franklin, D. W.
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Skilled control of visually-guided reaching is fundamental for many daily activities. Visual information about hand and target position are used for movement planning and online corrections through rapid visuomotor feedback responses. Such feedback control is generally believed to implicate a single error signal, representing a difference vector between hand and target position. Here, we directly assess whether shared or independent systems serve visually-guided feedback control. We tested whether feedback gains can be independently modulated by hand/cursor and target motion through manipulating the task-relevance of each signal during goal-directed reaching. Our results demonstrate that the gains of visuomotor feedback responses to perturbed hand and target motion can be set independently of one another, at the same time, as a function of task-relevance. By dissociating feedback control of cursor and target signals, our findings support the existence of two independent visuomotor feedback pathways, revealing a more flexible neural architecture for goal-directed action.
Khamina, M.; Wunsch, N.; Lupanga, U.; Fink, F.; Wang, H.; Schulze, W. X.; Schumacher, K.; Rubinstein, J. L.
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Vacuolar-type ATPases (V-ATPases) are evolutionarily conserved rotary proton pumps that play essential roles in the eukaryotic cell. By coupling ATP hydrolysis in their cytosolic V1 region to proton translocation through their membrane-embedded VO region, V-ATPases establish and maintain an acidic pH in the lumen of several different organelles. Functional diversity in the pump is enabled by multiple paralogous genes for the subunits of the complex, which are expressed in a tissue- and organelle-specific manner. Interactions between V-ATPase and TLDc domain-containing proteins have been shown to regulate the enzyme in yeast and mammals but their relevance in plants has remained unclear. We isolated the endogenous V-ATPase from Arabidopsis thaliana leaves and determined its structure by electron cryomicroscopy. Mass spectrometry showed that most of the enzyme originated from the tonoplast. The structural analysis revealed the full rotary catalytic cycle of the plant V-ATPase, and a combination of structural and biochemical experiments showed S-acylation of subunits AP1 and the tonoplast-specific subunit a3 isoform. A subpopulation of complexes derived from the trans-Golgi network/early endosome was identified and found to bind the TLDc protein OXR5. Together, these findings reveal plant-specific features in V-ATPase and suggest organelle-specific interactions with TLDc proteins, pointing to conserved but context-dependent V-ATPase regulation in eukaryotes.
Duncan, D. H.; Kandemir, G.; Olivers, C. N. L.
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Memorizing a new phone number or address is hard at first, but becomes easier with repetition, as information shifts from working memory to long-term memory. Here we investigated how repetition affects the storage and transition of different aspects of mnemonic information by comparing univariate neural markers of active object storage with multivariate decoding of memory content. Thirty participants encoded lateralized stimuli from a continuous shape space into memory. Memory items were repeated six times in a row to induce learning. In line with earlier work, EEG recordings revealed that repetition led to a reduction in contralateral delay activity (CDA), a measure of active storage that has been taken to reflect a pointer-like representation of the individual object or its original source. In contrast, shape decoding during the retention and also after an impulse perturbation remained constant across repetitions. These results suggest that learning over repetitions reflects the abolishment of active and individuated object memory representations while passive, source-independent memory representations are retained.
Pini, V.; Accorsi, A.; Kumar, A.; Muntoni, F.; Girgenrath, M.
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Laminin-2 (gene: LAMA2) is a key protein in the basement membrane of muscle and Schwann cells. A complete lack of this protein results in LAMA2-related congenital muscular dystrophy (LAMA2-RD), a severe muscle disease characterized by progressive muscle weakness, respiratory insufficiency, failure to thrive and shortened life span. One key signature of this disease is early onset of fibrosis coupled with poor muscle growth. We previously showed that TGF-{beta} and its activator, integrin-V, are elevated in dystrophic fibers of DyW mice, a mouse model of LAMA2- RD. Other than activating TGF-{beta}, integrin-V is also known to facilitate the transdifferentiation of various cell types to myofibroblasts. In this study we present evidence for transcriptional dysregulation of genes driving myofibroblast transdifferentiation and extracellular matrix (ECM) remodelling during the early development of DyW mice that is also reflected in muscle biopsies from young LAMA2-RD patients. We hypothesize that the early ECM remodelling, seen in both DyW mice and LAMA2-RD children, may explain the congenital onset of fibrosis with poor muscle growth seen in the disease.
Ji, X.; Cui, Q.
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Cell size is a critical morphological parameter determining cellular functional homeostasis, yet existing large-scale transcriptomic databases lack direct cell size measurement data. By integrating high-resolution immunofluorescence images with transcriptomics, we identified 457 genes significantly correlated with cell area. Based on these findings, we developed an algorithm, Cell Size Score (CSS), to predict cell size from gene expression profiles. Validation across multiple independent datasets, including human cell lines, mouse models, and single-cell spatial transcriptomics, confirmed that CSS accurately predicts cell size. Furthermore, we observed a significant positive correlation between CSS and broad-spectrum chemotherapy drug resistance, suggesting that increased cell volume confers survival advantages to cancer cells. Moreover, CSS analysis of aging revealed sex-dependent, tissue-specific patterns of change, wherein male adipose and cardiac tissues exhibited progressive hypertrophy with age, while female reproductive organs showed significant atrophy. Additionally, CSS significantly increased in skeletal muscle after exercise, indicating that this metric can capture dynamic physiological adaptation processes. This study establishes a bridge between transcriptomics and cell morphology, providing novel insights into retrospectively analyzing the role of cell size in pathological and physiological processes such as cancer and aging using existing omics data, as well as understanding the molecular mechanisms underlying cell size regulation.
Rytel, A.; van Bijlert, P. A.; Lautenschlager, S.; Spiekman, S. N. F.; Talanda, M.; Sulej, T.
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Extremely elongate necks have convergently evolved in several amniote lineages, including both aquatic and terrestrial forms (Fig. 1). The development of such a feature brings with it advantages in obtaining food items, but also biomechanical challenges, such as flexibility, stability, lift, and inertia. In Tanystropheus, a particularly long-necked Triassic archosauromorph, the neck is composed of only 13, mostly extraordinarily elongated and slender cervical vertebrae and accompanying rod-like, overlapping ribs, making it arguably the most extreme example of neck elongation in tetrapod evolution (Fig. 1;1-6). Understanding the function of this remarkable neck provides insights into the limits of neck elongation in amniotes and the evolution of morphological novelties in Triassic reptiles. Here we present the first quantitative biomechanical analysis of the Tanystropheus neck using a digital model based on three-dimensionally preserved bones. We assessed its range of motion (ROM) and performed finite element analysis (FEA) on the individual cervical ribs and the neck model in different configurations. Our results indicate that the neck of Tanystropheus was not extremely stiff, as previously postulated, and the ribs likely did not impair its movements. They transferred tensile forces towards the base of the neck, similar to what hypothesized for sauropods7. This study elucidates the bauplan of an extremely specialized animal and brings us closer to understanding the patterns of achieving neck elongation in vertebrates.
Adam, K. M.; Kuklinski, K. M.; Fisher, C. A.; Skinner, W. M.; Lo, J. Y.; Kochersberger, A.; Garrison, J. L.
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Oxytocin and vasopressin are endogenous bioactive peptides with conserved roles in reproduction and, more recently recognized, in peripheral lipid metabolism. Whether this signaling system also shapes how reproduction declines with age has not been tested in any animal. Here we show that in C. elegans, the oxytocin/vasopressin-like neuropeptide nematocin restrains reproductive output as animals reach mid-life. Nematocin and its two receptors are produced throughout adult life and peak as reproduction begins to wane. Animals lacking receptor signaling produce more offspring in mid-life, an improvement that reflects better egg quality and fertilization rather than improved embryo survival. This benefit is accompanied by changes in intestinal fat metabolism, the worm's equivalent of liver and adipose tissue: nematocin normally limits the activity of a fatty-acid desaturase that is otherwise induced by mating, and it shapes how much yolk reaches developing eggs. The two receptors act through separate routes, one tuning intestinal fat metabolism and the other controlling yolk delivery to the egg. Together, these findings reveal nematocin as a regulator of the intestinal metabolic environment across reproductive age, mirroring the recently described oxytocin-hepatocyte-adipocyte lipid axis in mammals and implicate this conserved signaling system in the coordination of maternal investment during reproductive aging.
Sheets, D. E.; Ruff, D. A.; Srinath, R.; Allen, K. S.; Morrison, J. H.; Cohen, M. R.
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Intelligent behavior depends on the brain's ability to represent multiple features of the environment simultaneously while keeping those representations independent [1,2]. Patients with Alzheimer's disease often mix up objects, people, and events [3-7], raising the possibility that disease mixes up the way that information is represented in the brain. Here we show that the independence of visual representations progressively breaks down during early stages of disease progression in a rhesus macaque model of Alzheimer's disease and related dementias [8-10]. In visual area V4, representations of different visual features become progressively less independent, such that the representation of one feature is increasingly influenced by the value of another. We term this loss of independence neuronal feature confusion. This neuronal change predicts a specific behavioral consequence: because feature representations become less independent, preferences associated with one visual feature increasingly influence visually guided choices associated with other, independent features. Using an analogous image-selection task, we found the same behavioral signature in people with mild cognitive impairment, distinguishing them from age-matched controls. These results identify a specific and measurable alteration in neuronal population representations that predicts a behavioral change observed across species. More broadly, these findings demonstrate that neuronal population representations can guide the development of sensitive, non-invasive behavioral methods for early detection of functional changes associated with Alzheimer's disease.