Forskningsradar

Science Journals

Peer-reviewade publikationer — 113 artiklar

Peroxisomal import is circadian in glia and regulates sleep and lipid metabolism
<p>by Anurag Das, Irma Magaly Rivas-Serna, Ankur Kumar, Lakpa Sherpa, Kerui Huang, Hia Kalita, Marlene Dorneich-Hayes, Ruiqi Liu, Vera C. Mazurak, John P. Vaughen, Hua Bai</p> Peroxisomes are critical organelles that detoxify cellular waste while also catabolizing and anabolizing lipids. How peroxisomes coordinate protein import and support metabolic functions across complex tissues and timescales remains poorly understood in vivo. Using the <i>Drosophila</i> brain, we discover a striking enrichment of peroxisomes in the neuronal soma and the cortex glia that enwrap them. Unexpectedly, import of peroxisomal proteins into cortex glia, but not neurons, oscillated across time and peaked in the early morning. Rhythmic peroxisomal import in cortex glia autonomously required the circadian clock and Peroxin 5 (Pex5; peroxisomal biogenesis factor 5 homolog), with import persistently elevated in clock mutants. Notably, reducing <i>Pex5</i> in cortex glia, but not neurons, caused hyperactivity and reduced total sleep. Moreover, brain lipid metabolism was dramatically altered upon <i>Pex5</i> knockdown, with glia impacting sphingolipids and triacylglycerols, and neurons impacting phospholipids. The cell-type specificity of these Pex5 phenotypes highlights unique roles for peroxisomal import in both sleep and lipid metabolism in the brain.
Neurons generated shortly after birth encode the scent of early-life happiness
<p>by Chloé Guillaume, Elisa Galliano</p> Smells linked to joyful childhood events trigger vivid memories in adulthood, yet the mechanism behind their formation has remained elusive. A new PLOS Biology study shows that neurons generated around birth play a key role in encoding these olfactory memories. Smells linked to joyful childhood events trigger vivid memories in adulthood, yet the mechanism behind their formation has remained elusive. This Primer explores a new study in PLOS Biology that shows that neurons generated around birth play a key role in encoding these olfactory memories.
Flight style and metabolism shape the tempo of genome evolution in birds
<p>by Yanzhu Ji, Lei Wu, Dongming Li, Shaohong Feng, Qi Fang, Ying Xiong, Yongbin Chang, Jacob C. Cooper, Xin Yu, Kai Zhang, Shiyu Tang, Huishang She, Huan Wang, Dezhi Zhang, Gang Song, Ping Fan, Jiaogen Zhou, Liang Ma, Yanhua Qu, Chenxi Jia, Catherine Sheard, James Andrew DeWoody, Joseph A. Tobias, Guojie Zhang, Weiwei Zhai, Fumin Lei</p> As a hallmark of avian ecological innovation, powered flight has fundamentally shaped diverse aspects of birds. The energy demand of flight may have mutagenic impacts on genomes, influencing how fast genomes evolve. However, the relationship between flight, metabolism, and evolutionary rates remains relatively underexplored. Leveraging 363 newly available avian genomes from >90% of avian families, we quantified three distinct types of genomic evolutionary rates to capture a broad spectrum of mutational processes. By combining four flight-related traits and three metabolic metrics, we uncovered significant associations between flight style, metabolism, and multiple evolutionary rates. Next, using a causal inference framework, we demonstrated that metabolism accounted for 43.3% of the total effect between flight and evolutionary rate, underscoring its key role. Together, our findings establish a robust connection between flight, metabolism, and evolutionary rates, offering new insights into how key innovations and associated phenotypes shape the tempo of genome evolution.
Realistic monkey body animation reveals an uncanny valley in macaque body perception
<p>by Lucas M. Martini, Anna Bognár, Rufin Vogels, Martin A. Giese</p> Social interactions are essential for survival in primates, relying on both facial expressions and body signals. The accurate characterization of these signals is critical for understanding the neurocomputational mechanisms underlying social communication. While previous work has focused on recognizing monkey behavior, a causal and direct manipulation of individual cues strongly benefits from believable, dynamic body avatars—analogous to those successfully developed for faces. Creating lifelike monkey avatars with realistic body motion, however, is challenging. Acquiring sufficiently accurate movement data for animation with marker-based motion capture is impractical, and markerless tracking methods require extensive manual labeling. To address this, we developed MacAction, a realistic macaque body avatar animated from multi-camera markerless tracking data. Our method reconstructs accurate trajectories for a large number of keypoints, as required for the 3D animation of realistic body models. The entire time course of individual actions is captured using only two labeled keyframes per second, with performance further validated on a large-scale human multi-view dataset. We assessed the animation quality of our dynamic avatar in a free-viewing experiment with eight macaque observers for single macaque actions, where fixation behavior was indistinguishable between our animations and matched real videos. Moreover, by systematically varying the realism of the avatar, we found an uncanny valley effect in macaque body perception, similar to that previously described in both humans and macaque faces. These findings support the commonalities of social vision across primate species, providing a foundation for controlled experiments aimed at clarifying the detailed neurocomputational mechanisms of social body perception in primates.
Dachsous-Fat signaling shapes the <i>Drosophila</i> wing through mechanical forces
<p>by Bipin Kumar Tripathi, Zhenru Zhou, Kenneth D. Irvine</p> Proper organ shape is critical for function. The <i>Drosophila</i> wing normally adopts an elongated shape, but mutations in the Dachsous-Fat pathway result in rounder wings. The mechanism by which this occurs has remained unclear. Here, we show that Ds-Fat signaling shapes the wing during the larval stage, rather than during pupal development when morphogenetic rearrangements transform the developing wing disc into the adult wing. We further find that Ds-Fat alters tissue-wide stresses in the wing disc, and genetic manipulations that reduce cytoskeletal tension result in rounder wings, whereas increasing cytoskeletal tension produces more elongated wings. Reduced tension is also associated with less oriented growth during development. Notably, increased cytoskeletal tension partially rescues the rounder shape caused by <i>ds</i> knockdown. These results reveal a previously unrecognized mechanism by which Ds-Fat signaling determines wing shape, involving regulation of tissue tension to orient growth and shape the wing primordia during larval development.
Positive early-life olfactory memory is rooted in the olfactory bulb and triggers large-scale changes beyond the olfactory system
<p>by Jules Dejou, Anna Athanassi, Théo Brunel, Marc Thevenet, Anne Didier, Nathalie Mandairon</p> Olfactory childhood memories are particularly important for forming one’s identity. However, we don’t know how they exert their privileged influence and shape brain structure. To address this, we modeled childhood olfactory memory in mice based on a human survey indicating that our earliest olfactory memory arises from repeated positive experiences paired with a pleasant odorant. Accordingly, mice were exposed during childhood to an attractive odorant in a playful environment. In adulthood, memory recall relied on neonatal-born granule cells (GCs) in the olfactory bulb, as their optogenetic silencing impaired retrieval, and on increased functional connectivity in the reward system. With age, memory persistence depended on re-exposure to the childhood odorant and was associated with the disengagement of neonatal-born GCs, alongside with strengthened limbic functional connectivity. Together, these findings identify neonatal neurons as a key substrate for encoding childhood olfactory memory and reveal dynamic reorganization of brain networks supporting its long-term significance.
Meis1 isoform diversity orchestrates neural progenitor differentiation by regulating ATOH1 degradation at distinct subcellular compartments
<p>by Tomoo Owa, Toma Adachi, Ryo Shiraishi, Kentaro Ichijo, Kaiyuan Ji, Minami Mizuno, Kyoka Suyama, Kayo Nishitani, Ikuko Hasegawa, Masaki Sone, Daisuke Kawauchi, Tomoki Nishioka, Shinichiro Taya, Yutaka Suzuki, Kozo Kaibuchi, Satoshi Miyashita, Mikio Hoshino</p> The development of the complex nervous system is strictly controlled by diverse isoforms produced from individual genes, but the underlying machinery remains unclear. Our long-read cDNA sequencing of mouse cerebellar granule cell progenitors (GCPs) identifies more than 700 genes with high isoform diversity. One such gene, <i>Meis1</i>, produces MEIS1-FL and MEIS1-HdL isoforms, which include and lack the homeodomain, respectively. Our previous study showed that MEIS1-FL localizes to nuclei and promotes ATOH1 protein degradation through transcriptional regulation, thereby promoting GCP differentiation. In contrast, our in vivo electroporation experiments in the postnatal mouse cerebellum show that MEIS1-HdL inhibits GCP differentiation. MEIS1-HdL localizes in the cytoplasm and inhibits the degradation of ATOH1 mediated by CUL3, which is a newly identified E3 ligase for ATOH1. MEIS1-HdL enhances the binding of the COP9 signalosome to CUL3, which suppresses ATOH1 polyubiquitination. This study demonstrates that functionally antagonistic isoforms derived from a single gene cleverly control neural progenitor differentiation.
Social learning dynamically shapes moral decision-making by biasing subjective valuation
<p>by Julien Benistant, Valentin Guigon, Alain Nicolas, Edmund Derrington, Jean-Claude Dreher</p> Observing immoral behavior increases one’s dishonesty by social influence and learning processes. The neurocomputational mechanisms underlying such moral contagion remain unclear. We tested different mechanistic hypotheses to account for moral contagion. We used model-based fMRI and a new cheating game in which participants were sequentially placed in honest and dishonest social norm contexts. Participants’ cheating behavior increased in the dishonest norm context but was unchanged in the honest one. The best model to account for behavior indicated that participants’ valuation was dynamically biased by learning that others had cheated. At the group level, this valuation bias was not encoded by any specific brain region. Instead, this neural signal depended on individual differences in conformity, and engaged the bilateral lateral prefrontal cortex. During learning, simulation of others’ cheating behavior was encoded in the posterior superior temporal sulcus. Together, these findings provide a mechanistic understanding of how learning about others’ dishonesty biases individuals’ valuation of cheating but does not alter one’s established preferences.
Wanting this, not that: The neural circuit that turns specific expectations into actions
<p>by Joey A. Charbonneau, Erin L. Rich</p> Neuroeconomics has long focused on reward values, ignoring their identity. A new PLOS Biology study shows that identity-specific reward expectations in the lateral orbitofrontal cortex steer goal-directed choices through a motivational circuit involving the nucleus accumbens. Neuroeconomics has long focused on reward values, ignoring their identity. This Primer explores a new study in PLOS Biology that shows that identity-specific reward expectations in lateral orbitofrontal cortex steer goal-directed choices through a motivational circuit involving nucleus accumbens.
Identity-specific reward expectations in orbitofrontal cortex guide goal-directed choices
<p>by Phillip P. Witkowski, Noelle Henein, Nicole Moussa, Geoffrey Schoenbaum, Thorsten Kahnt</p> Real-life decisions are typically directed toward specific types of rewards (e.g., a slice of pizza or a bowl of pasta), but reward identity is often neglected in neuroeconomic theories of decision-making. Previous research has shown that the lateral orbitofrontal cortex (lOFC) represents the specific rewards predicted by environmental cues. However, whether and how these expectations influence decision-making remains an open question. To address these questions in humans, we developed a novel behavioral task in which Pavlovian cues associated with specific rewards are presented before participants can make decisions to forage these rewards. Using pattern-based analysis of functional magnetic resonance imaging data, we show that cues predicting distinct reward types evoke identity-specific expectations in lOFC, which in turn predict subsequent choices. This effect is amplified by activity in the nucleus accumbens, which enhances the influence of lOFC reward expectations on action representations in the dorsal anterior cingulate cortex. These results connect representational and motivational accounts of decision-making, highlighting the neural mechanism by which expectations about reward identity guide goal-directed behavior.
Dipteran flight diversity is shaped by aerodynamic constraints, scaling, and evolutionary trade-offs
<p>by Camille Le Roy, Ilam Bharathi, Thomas Engels, Florian T. Muijres</p> Flight has been a key innovation in insect evolution, yet the selective and mechanistic pressures shaping their flight motor systems remain poorly understood. Here, we present a comprehensive comparative analysis of flight in Diptera (true flies), integrating morphology, wingbeat kinematics, and aerodynamics within a phylogenetic framework. We quantified morphology in 133 species spanning the Dipteran phylogenetic and size range, and for a subset of 46 species, we combined high-speed stereoscopic videography with computational fluid dynamics (CFD) to characterize wingbeat kinematics and aerodynamic performance, respectively. Our results reveal that morphology is strongly structured by phylogeny, whereas wingbeat kinematics are broadly conserved across Diptera, reflecting dominant aerodynamic constraints. Two early-diverged lineages, Culicomorpha (mosquitoes and midges) and Tipulomorpha (crane flies), exhibit strikingly divergent kinematics and aerodynamics, suggesting lineage-specific selective pressures. Combining these data with scaling analyses shows that maintaining in-flight weight support across the dipteran size range requires systematic allometric adjustments in wing morphology, wingbeat kinematics, and flight musculature. Smaller dipterans achieve weight support through relatively larger wings and higher wingbeat frequencies, whereas larger dipterans achieve the same aerodynamic requirement through increased investment in flight musculature to sustain the necessary mechanical power output. These size-dependent trait combinations highlight how different morphological and kinematic adaptations evolved in response to the shared physical requirements of hovering flight across Diptera. Mosquitoes and midges represent an extreme case, exhibiting a pronounced aerodynamic–acoustic trade-off with disproportionately high wingbeat frequencies, large flight musculature and increased aerodyna…
GABA neurons in the sublaterodorsal tegmental nucleus suppress wakefulness in healthy and narcoleptic mice
<p>by HanHee Lee, Jimmy J. Fraigne, John H. Peever</p> The sleep-wake cycle is generated by competing neural circuits that control the oscillation between wakefulness, rapid eye movement (REM) sleep, and non-REM (NREM) sleep. While the sublaterodorsal tegmental nucleus (SLD) is recognized for its role in REM sleep generation, the functional contribution of its GABAergic neurons (SLD<sup>GABA</sup>) to sleep-wake regulation remains poorly understood. Here, we found that SLD<sup>GABA</sup> neurons function as a suppressor of wakefulness in both healthy (i.e., <i>orexin</i><sup>+/+</sup>) and narcoleptic (i.e., <i>orexin</i><sup>−/−</sup>) mice. In healthy mice, optogenetic silencing of SLD<sup>GABA</sup> neurons rapidly induced robust wakefulness, while enhancing cortical and motor activity. Conversely, optogenetic activation of these neurons suppressed wakefulness and promoted NREM sleep. We found traces of SLD<sup>GABA</sup> axonal projections to wake-promoting brain regions, providing an anatomical basis for their wake-suppressing effects. Importantly, we discovered that SLD<sup>GABA</sup> neurons play a pathological role in narcolepsy: their activation in orexin-deficient narcoleptic mice triggered characteristic sleep attacks—rapid intrusions of NREM sleep during active wakefulness—while silencing these neurons rescued animals from both sleep attacks and cataplexy. Collectively, these findings establish SLD<sup>GABA</sup> neurons as a key regulator of arousal state transitions and identify them as a novel therapeutic target for the treatment of narcolepsy.
A developmental shift in glucocorticoid receptor expression preserves glucocorticoid sensitivity in the adult suprachiasmatic nucleus
<p>by Kristian Händler, Varun K. A. Sreenivasan, Violetta Pilorz, Celia Martinez-Perez, Iratxe Elorduy, Tomas J. Casas, Marianne Lehmann, Jon Olano Bringas, Laura Escobar Castañondo, Nora Bengoa-Vergniory, Federico N. Soria, Henrik Oster, Malte Spielmann, Mariana Astiz</p> The circadian system synchronizes physiology, improving the adaptation to daily environmental changes. In mammals, the central pacemaker, in the suprachiasmatic nuclei (SCN) of the hypothalamus, coordinates “wake” functions by inducing the circadian release of glucocorticoids (GCs). GCs entrain the clocks of a wide variety of tissues through GC receptor (GR) activation, however, the influence of GCs on the SCN is unclear and seems to depend on the maturity of the circuit. During the perinatal period, the mouse SCN express GR and respond directly to GCs while the adult SCN express low GR and have been traditionally considered resistant to GCs. To understand the change of sensitivity to GCs we followed the developmental trajectory of the mouse SCN, and found that while GR is expressed in all SCN cells early in life, it remains expressed mainly in astrocytes in the adult. Using a model of prenatal exposure to GCs, we found that offspring from treated mothers, adapt slower to shifted light–dark cycle and shows reduced expression of GR in SCN astrocytes. The adult SCN astrocytes can indeed sense and respond to GCs with rapid astrocytic Ca<sup>2+</sup> events that propagate across neighboring cells, an effect that is prevented by the specific inhibition of astrocyte–astrocyte communication. Our findings provide a conceptual advance on how the mouse clock develops and on the influence that GCs have on the SCN. This might be relevant to understand how circadian synchrony is restored in conditions of temporal misalignment, such as jet lag.
Shared memories of event details in the human brain are altered by misinformation and test expectations
<p>by Xuhao Shao, Chuansheng Chen, Elizabeth F. Loftus, Bi Zhu</p> Shared memories of event details are crucial to eyewitness testimony. When different people encode or recall the same event, similar scene-specific neural activity patterns emerge across individual brains. However, it remains unclear whether these patterns are specific to event details and how test expectancy (i.e., expecting free recall or general memory tests) and misinformation affect them. In this study, 100 participants were randomly assigned to view one of two versions of each event. Both versions featured identical scenarios, but with different details. About half of the participants were informed about the upcoming free recall before viewing events, while the others were told to expect a general memory test. Functional magnetic resonance imaging was used to record their brain activity during four stages: viewing original events, initial free recall, reading misinformation, and final free recall of original events. The neuroimaging data were analyzed based on the similarity of neural patterns across participants. Test expectancy increased the similarity of detail-specific neural activity patterns between individuals when they viewed original events in brain regions relevant for visual attention. Misinformation increased the likelihood of people forming shared false memories of event details. People who formed shared false memories exhibited similar detail-specific patterns of activity in the dorsomedial prefrontal cortex when reading misinformation. People who formed shared true memories exhibited similar detail-specific patterns of activity in the inferior parietal lobe when viewing original events, as well as in the ventrolateral prefrontal cortex and middle temporal gyrus when recalling them after exposure to misinformation. Our findings revealed that different brain regions of the default mode network play distinct roles in the encoding and recall of event details shared by individuals.
Resistance potentiators: Evolutionary catalysts of antibiotic resistance
<p>by R. Craig MacLean, Adam Mulkern, Liam P. Shaw</p> Why do even closely-related bacteria differ in their capacity to evolve antibiotic resistance? Drawing on evidence from experimental evolution, pathogen genomics, and molecular microbiology, this Essay argues that the evolution of antibiotic resistance in bacterial genomes is frequently catalyzed by the presence of ‘resistance potentiators’: genes, elements, or pathways that accelerate evolution in a trait-specific manner. Epidemiological evidence suggests that resistance potentiators that modulate phenotypes have been particularly important in successful pathogen lineages. Furthermore, experimental models show that combining antibiotics with inhibitors of resistance potentiators can restrict the evolution of resistance, suggesting that they could be future drug targets or otherwise lead to more evolution-informed antibiotic therapy.
Engineering resilient gene drives for sustainable malaria control by predicting, testing and overcoming target site resistance in <i>Anopheles gambiae</i>
<p>by Ioanna Morianou, Lee Phillimore, Bhavin S. Khatri, Louise Marston, Matthew Gribble, Austin Burt, Federica Bernardini, Andrew M. Hammond, Tony Nolan, Andrea Crisanti</p> CRISPR-based gene drives are selfish genetic elements with the potential to spread through entire insect populations for sustainable vector control. Gene drives designed to disrupt the reproductive capacity of females can suppress laboratory populations of the malaria mosquito, <i>Anopheles gambiae</i>. However, any suppressive intervention will inevitably exert an evolutionary pressure for resistance, and the likelihood of resistance emerging at natural population scales remains poorly defined. Here, we present a pipeline to quantify the evolutionary space for resistance, enabling accelerated discovery, engineering, and testing of both natural and drive-induced variants that could reverse gene drive spread. We applied our approach to stress-test a best-in-class suppression gene drive that has evaded resistance in all laboratory-contained releases to date, known as Ag(QFS)1. We showed that previously undetected resistant alleles can arise at low frequency, including a novel type of partially resistant alleles that can perturb drive-invasion dynamics. Integrating experimentally derived resistance rates with population genetic modeling shows that single-target suppression drives are unlikely to be robust at natural mosquito population sizes, even at highly constrained loci. Here, we engineer and validate multiplexed gene drives in <i>Anopheles gambiae</i>, that target multiple conserved sites, actively removing resistant alleles. Our models predict that such gene drives could supress large natural mosquito populations in the field.
Sequential neural dynamics underlie unconscious integration and conscious perception of visual stimuli
<p>by Maëlan Q. Menétrey, Michael H. Herzog, David Pascucci</p> In some forms of postdictive phenomena, later events influence the perception of earlier ones, suggesting that conscious perception may be preceded by extended periods of unconscious processing. An example is the Sequential Metacontrast (SQM) paradigm, in which vernier offsets are unconsciously integrated over several hundred milliseconds before conscious perception. Obviously, the integrated percept can only emerge after each individual element in the stream has been processed. Thus, the SQM provides a unique opportunity to dissociate unconscious from conscious stages of visual processing, as these stages are well separated in time. Using electroencephalography (EEG) recordings in human participants during the SQM, we identified two distinct stages of neural activity: an early occipital EEG activity pattern (~200 ms after the initial vernier) associated with unconscious processing, and a later centro-parietal EEG pattern (~400 to 600 ms after SQM onset) associated with the integrated percept and the behavioral report. We propose that the transition between these neural patterns marks the shift from unconscious encoding of individual visual stimuli to their integrated percept.
Disinhibitory signaling enables flexible coding of top-down information in cortical networks
<p>by Tomas G. Aquino, Robert Kim, Nuttida Rungratsameetaweemana</p> Flexible behavior requires the ability to modulate sensory processing based on task context, yet the circuit-level mechanisms supporting this capacity remain poorly understood. Here, we combine recurrent neural network modeling and neural recordings from mouse visual cortex to investigate how task context shapes sensory coding. Networks trained on an instruction-based discrimination task develop a disinhibitory interneuron-to-interneuron motif that dynamically gates task-relevant sensory information. Perturbation and lesion analyses show that this motif is necessary for task performance and for maintaining distinct sensory representations across contexts. We validate key predictions in mouse visual cortex, where interneuron activity patterns exhibit comparable task-dependent modulation. These results identify a biologically plausible circuit motif that supports flexible sensory processing and link recurrent connectivity structure to adaptive context integration in both artificial and biological systems.
The cell cloud: Adopting systems biology concepts in the era of single-cell immunology
<p>by Tal Shay, Christophe O. Benoist, Ricardo Grieshaber-Bouyer</p> High-throughput single-cell assays reveal data that defies discrete categorization. The ‘cell cloud’ model, grounded in established systems biology principles, offers a framework to navigate biological plasticity alongside technical variability. Immune cells exist as continuous clouds, not discrete categories. In this Perspective, authors from the Immunological Genome Project reframe immune identity through systems biology, and redirect where immunotherapies should aim: at the dynamics of the cloud, not just its center.
Correction: Cdc42 interacts with chaperone Ydj1 to enhance its stability and partitioning during asymmetric cell division and aging in yeast
There are a number of errors in the caption for Fig 4, “Farnesylated Ydj1 is required for maintaining Cdc42 levels and its asymmetric distribution,” panels A-C. Please see the complete, correct Fig 4 caption here. A. Localization of Cdc42-mCherrySW in WT and ydj1 mutants at 27°C. Arrows mark examples of large-budded cells used for Cdc42 quantification in B & C. Scale bar: 3 µm. B. Cdc42-mCherrySW levels in mother (m) and bud (b) compartments of large-budded ydj1Δ cells, grown at 27°C. (left plot) Mean fluorescence intensities from 19 representative mother-bud pairs are plotted. ns, p ≥ 0.05, paired t test. (right plot) The log2 mother-to-bud ratio of Cdc42-mCherrySW mean intensity in WT and ydj1 mutants (n = 52 per strain). The dotted line denotes a symmetric distribution of Cdc42 between mother and bud. **** p < 0.0001 by one-way ANOVA. See also S3D Fig. C. Cdc42 levels in WT and ydj1 mutants, grown at 27°C to mid-log phase. Mean fluorescence intensities of Cdc42-mCherrySW in whole cells (mother and bud combined) are plotted. n = 57 ~ 60 per strain; **** p < 0.0001, unpaired t-tests. Immunoblotting shows Cdc42-mCherrySW in each strain, detected using polyclonal anti-RFP antibodies, and α-tubulin, a loading control. See also S3C Fig. D. Association of Cdc42-mCherrySW with GFP-Ydj1 detected by a visible IP assay (top panel). A control reaction used extracts containing untagged Ydj1 (bottom panel). The data underlying the graphs can be found in S1 Data. A. Localization of Cdc42-mCherrySW in WT and ydj1 mutants at 27°C. Arrows mark examples of large-budded cells used for Cdc42 quantification in B & C. Scale bar: 3 µm. B. Cdc42-mCherrySW levels in mother (m) and bud (b) compartments of large-budded ydj1Δ cells, grown at 27°C. (left plot) Mean fluorescence intensities from 19 representative mother-bud pairs are plotted. ns, p ≥ 0.05, paired t test. (right plot) The log2 mother-to-bud ratio of Cdc42-mCherrySW mean intensity in WT and ydj1 mutants (n = 52 per strain).…
Towards globally equitable bioinformatics adoption
<p>by Paulyna Magaña, Piraveen Gopalasingam, Jennifer R. Fleming, Oleg Kovalevskiy, Augustin Žídek, ThankGod Echezona Ebenezer, Agata Laydon, Roz Onions, Eva Akurut, Syed Muktadir Al Sium, Yalbi Itzel Balderas-Martínez, Sanjana Fatema Chowdhury, Saikat Chowdhury, Sylvia Christie, Govinda Rao Dabburu, Fatoumata Gnine Fofana, Ronald Galiwango, Mahipal Ganji, Daudi Jjingo, Fredrick Elishama Kakembo, Grace Kebirungi, Shahiid Kiyaga, Ayoub Ksouri, Sanjeet Kumar Mahtha, Vinicius Maracaja-Coutinho, Jack Mason, Jose Arturo Molina-Mora, Patricia P. N. Nabisubi, Emmanuel Nji, Houcemeddine Othman, Martina Soledad Paoletta, Nicole M. Scherer, Bhagya Senadheera, Adrián Gustavo Turjanski, David Twesigomwe, Andrew Walakira, Sameer Velankar, Cath Brooksbank</p> Advances in artificial intelligence (AI)-driven bioinformatics promise democratized discovery, yet major inequities persist. Equitable adoption of bioinformatics tools will require sustained investment in infrastructure, training, institutions, and global communities, not just access. Advances in AI-driven bioinformatics promise democratized discovery, yet major inequities persist. This Perspective uses AlphaFold as an illustrative case to argue that equitable adoption of bioinformatics technologies will require sustained global investment, not just provision of access.
Unusual decay: Recombination loss leads to splicing errors in green algae
<p>by Anamaria Necsulea</p> Recombination suppression leads to genomic erosion through an accumulation of deleterious mutations. A new study in PLOS Biology reveals an outstanding increase in aberrant splicing in non-recombining genomic regions in green algae. Recombination suppression leads to genomic erosion through an accumulation of deleterious mutations. This Primer discusses a new study that reveals an outstanding increase in aberrant splicing in non-recombining genomic regions in green algae.
The human claustrum supports cognitive networks for externally and internally driven task demands
<p>by Brent W. Stewart, Matthew A. Cormie, Michael L. Keaser, Massieh Moayedi, Brian N. Mathur, David A. Seminowicz</p> Cognitive control is believed to arise from task-dependent interactions among networks of brain regions. Although several debilitating neuropsychiatric disorders are characterized by cognitive network dysfunction, the neural circuit mechanisms supporting task-dependent network activity are largely unknown. External and internal task demands elicit opposing responses from key cognitive networks, and claustrum projections target regions associated with both network states. We tested if claustrum supports task-dependent network activity in humans using fMRI during tasks with externally and internally driven demands: working memory (<i>n</i> = 420) and autobiographical memory (<i>n</i> = 35). Claustrum activity increased in both tasks. Claustrum exhibited anatomical connectivity with regions representing all implicated networks, and claustrum effective connectivity suggested an excitatory influence on regions in multiple task-associated networks. Task response and connectivity measures differed between the claustrum and regions prominently implicated in directing network states—the anterior insula and pulvinar. These findings establish a role for the claustrum in supporting task-dependent network states subserving cognitive control.
Splicing deficiency is driven by genomic erosion in non-recombining algal mating-type chromosomes
<p>by Chris Condon, Andrea Galvez, Alexander Kramer, Landen Gozashti, Chris Vollmers, Manuel Ares Jr., Russell Corbett-Detig</p> Splicing deficiency may represent a critical yet underexplored form of genomic erosion in non-recombining regions. Across four phytoplankton species diverged ~333–639 million years ago, genes within U (female) and V (male) “UV” mating-type regions—non-recombining chromosomal regions that determine mating compatibility—show strikingly elevated intron retention relative to genes in other genomic regions. Long-read data reveal abundant aberrant, likely non-functional mRNA isoforms despite preserved coding potential. This preservation suggests that splicing defects arose early in UV evolution and have persisted over deep time. We propose that these defects arise from evolutionary changes in sequence composition and chromatin organization that accompany recombination suppression, such as reduced GC content, altered nucleosome occupancy, and disrupted methylation, that collectively compromise splicing fidelity. Unlike sex chromosomes, which often degenerate through gene loss, splicing-deficient UV regions in green algae retain hundreds of genes, indicating that transcript-level dysfunction provides an alternative route to functional decay. Our results identify chromatin-mediated splicing deficiency as a novel axis of genomic erosion and position algal UV systems as models for studying how recombination suppression reshapes RNA processing fidelity in essential, non-recombining genomes.
Engineered bipaternal mice reveal the consequences of life without a maternal genomic contribution
<p>by Si-Nan Ma, Fan Li, Yu-Long Zhao, Xue-Han Sun, Xue-Song Chen, Tian-Shi Pan, Qing-Tong Shan, Chao Liu, Gui-Hai Feng, Zhi-Kun Li, Qi Zhou, Wei Li</p> Successful mammalian development normally requires contributions from both maternal and paternal genomes, yet how these parental components jointly shape organismal development remains incompletely understood. Using engineered bipaternal mice generated from androgenetic embryonic stem cells carrying extensive imprinting-region modifications and produced through tetraploid complementation, we examined developmental and physiological consequences of development supported exclusively by paternal genomes. Placental analyses revealed partial normalization of placental growth but persistent differences among conceptuses. Transcriptomic profiling across embryos and postnatal tissues similarly showed broad alterations in gene expression states involving both imprinted and non-imprinted genes. Despite these differences during development, adult physiology showed a more coherent endpoint: integrated transcriptomic and metabolomic analyses revealed that adult livers converge toward an altered metabolic configuration characterized by coordinated perturbations of the tricarboxylic acid cycle and associated lipid metabolism, accompanied by hepatic lipid accumulation and increased systemic fat mass. These findings indicate that paternal-only mammalian development can proceed across multiple stages but follows altered developmental trajectories that culminate in distinct physiological states, providing insight into how maternal and paternal genomic contributions interact to shape mammalian development and physiology.