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bioRxiv2025

Disruption of the developmental factor Otp in the adult forebrain reveals its diverse physiological functions

Orthopedia (Otp) transcription factor is a critical determinant in the development of the neuroendocrine hypothalamus, and its embryonic deletion results in lethality. Although Otp expression is maintained throughout life, its physiological function in adulthood is not well understood. Here, we generated a forebrain-specific, tamoxifen-inducible, conditional knockout mouse model to investigate the roles of Otp beyond development. Conditional deletion of Otp in two-month-old mice resulted in impaired stress responses, characterized by increased depressive-like behavior and elevated stress-induced cortisol levels. It also led to various metabolic changes, including reduced thyroid hormone levels and body temperature, a higher percentage of fat mass, and diminished responsiveness to ghrelin without affecting food intake, energy expenditure, or body weight. This composite metabolic phenotype was associated with reduced hypothalamic neuropeptides TRH, CRH, AgRP, and NPY expression. Our findings highlight the role of Otp in adult physiological functions as a key neuroendocrine integrator of adaptive stress response and energy balance.

neuroscience↗

bioRxiv2025

Strain-dependent contribution of the AcrAB-TolC efflux pump to Klebsiella pneumoniae physiology

Klebsiella pneumoniae is a prominent opportunistic pathogen increasingly associated with multidrug resistance and virulence. One of the main mechanisms of antimicrobial resistance in K. pneumoniae is active efflux, primarily mediated by the Resistance-Nodulation-Division (RND) family of pumps. AcrAB-TolC is the key RND efflux pump in K. pneumoniae, regulated by the transcriptional activator RamA and its repressor RamR. Although overexpression of AcrAB-TolC has been linked to drug resistance in various clinical strains, its physiological roles in K. pneumoniae remain insufficiently studied. In this study, we generated isogenic deletions of acrB and ramR in both the genetically tractable K. pneumoniae Ecl8 and the virulent ATCC 43816 strains. We examined the phenotype of the {Delta}acrB and {Delta}ramR mutants by assessing antimicrobial susceptibility, biofilm formation, growth under infection-related conditions, and both in vitro and in vivo infection models. Loss of acrB increased susceptibility to drugs, decreased biofilm formation, and reduced in vitro virulence in both Ecl8 and ATCC 43816. However, only in Ecl8 was the loss of AcrB found to diminish growth under infection-like conditions and decrease in vivo virulence in the Galleria mellonella infection model. In contrast, in ATCC 43816, it had no effect. Our findings suggest that AcrAB-TolC exhibits strain-specific physiological functions, highlighting its dual role in antimicrobial resistance and pathogenicity, and thereby broadening our understanding of efflux-mediated adaptations in K. pneumoniae. Exploring the broader functions of RND efflux pumps in K. pneumoniae can provide insights into the potential effects of targeting them with inhibitor molecules. ImportanceInfections caused by multidrug-resistant bacterial pathogens are among the most urgent global public health challenges. Specifically, Klebsiella pneumoniae is classified by the World Health Organisation as a critical priority pathogen for the development of new treatments. Resistance-Nodulation-Division (RND) efflux pumps significantly contribute to multidrug resistance and virulence, making them promising targets for drug development. In this study, we demonstrated that the RND efflux pump AcrAB-TolC in K. pneumoniae is essential for drug efflux, biofilm formation, and in vitro virulence. Notably, we identified strain-specific roles for AcrAB-TolC in supporting growth under infection-related conditions and virulence in the Galleria mellonella infection model. Our findings highlight that the function of RND efflux pumps can vary between strains within a species. This implies that targeting RND efflux pumps with inhibitors may yield different effects depending on the strain background.

microbiology↗

bioRxiv2025

Adolescent alcohol exposure disrupts extinction learning and retrosplenial cortex physiology in adult males

Adolescent binge drinking can lead to a myriad of issues in adulthood, including psychiatric comorbidities that worsen clinical prognosis. Efforts to understand the effects of adolescent alcohol exposure on later health outcomes have unveiled lasting effects on physiology of brain regions critical for associative learning processes, including the hippocampus and prefrontal cortex (PFC). Here, we tested the hypothesis that adolescent alcohol exposure would produce lasting alterations in physiology within the retrosplenial cortex (RSC), another region critical for associative learning that is reciprocally connected to the hippocampus and PFC. In support of this hypothesis, we found that adolescent intermittent ethanol (AIE) vapor exposure resulted in lasting reductions in intrinsic excitability in RSC pyramidal cells of adult mice. Importantly, these changes were sex-specific, occurring in males but not females. This work suggests that the RSC may be a key, vulnerable locus to the detrimental effects of adolescent alcohol.

neuroscience↗

bioRxiv2025

Characterization and deorphanization of RYamide signaling in Aedes aegypti: a potential regulator of hindgut-associated physiology

Neuropeptide Y-related signaling, consisting of various neuropeptides and their receptors including, for example, the mammalian neuropeptide Y (NPY), pancreatic polypeptide (PP), and peptide YY (PYY) families, along with neuropeptide Y-like peptides in insects, is evolutionarily conserved across vertebrates and invertebrate organisms. Vertebrate NPY is known as an important regulator of energy homeostasis and feeding behaviour, while studies on one NPY-associated signaling system in arthropods, known as RYamide, have mainly focused on functions regulating feeding-related behaviours. The current study aimed to begin exploring an additional functional role of RYamide signaling related to excretory physiology in Aedes aegypti given that a candidate RYamide receptor, RYaR2, is enriched in the hindgut of adult mosquitoes based on publicly available RNA-seq databases. Herein, we report that the RYamide transcript is expressed in all post-embryonic stages with greatest abundance in adult male mosquitoes. Specifically, the central nervous system and the ventral nerve cord were demonstrated as the major sources of RYamide, as supported by RT-qPCR and intense RYamide immunoreactivity observed in the protocerebral posterior dorsomedial neurons and protocerebral anterolateral neurons in the mushroom body region, along with an intensively stained pair of neurons in the terminal abdominal ganglion (TAG). The pair of immunoreactive neurons in the TAG contain elaborate processes extending onto the hindgut, with a branch extending posteriorly over the rectum where fine processes are in close proximity to the rectal papillae (pads) while an anterior branch extends over the ileum terminating at the midgut-hindgut junction forming a fine circular plexus over the pyloric valve. Importantly, two orphan GPCRs, previously referred to as NPYLRs, were functionally deorphanized as bona fide RYamide receptors. Their responses to diverse peptidergic ligands were assessed, revealing that RYamides elicited the strongest receptor activation, with half maximal effective concentrations in the pico- to nanomolar range. Notably, our phylogenetic analysis revealed that while only a single RYaR is commonly found across most arthropods, culicine mosquito species including A. aegypti possess two RYaRs. The characterization of RYamide signaling with respect to excretory physiology involving the hindgut, particularly in species having two receptor isoforms such as culicine mosquitos, may provide valuable insights for development of novel, species-specific pest control strategies.

zoology↗

bioRxiv2025

Combining the alpha-2 adrenergic agonist clonidine with naloxone rescues fentanyl-induced physiologic dysfunction and increases survival

Fentanyl leads to tens of thousands of overdose deaths every year despite widespread availability of naloxone. Like other opioids, fentanyl causes respiratory depression. Unlike morphine, high dose fentanyl rapidly produces airway obstruction, muscle rigidity, and cardiovascular failure. Using a rat model of opioid overdose, we compared the physiological effects of fentanyl and morphine and studied the efficacy of a novel rescue strategy. In contrast to morphine, we report that fentanyl more frequently causes respiratory failure secondary to vocal cord closure and leads to more severe cardiovascular disruption, including the blockade of baroreflex-like rebound in blood pressure. We also show that administration of intramuscular naloxone immediately after intravenous infusion of fentanyl did not improve survival. However, combining intramuscular naloxone with the alpha-2 adrenergic agonist clonidine rescued vocal cord function and stabilized cardiovascular and respiratory physiology from fentanyl-induced effects. Our findings demonstrate that fentanyl is associated with a unique and more severe toxidrome compared to morphine. Also, supplementing naloxone with drugs targeting the adrenergic system improves survival primarily by reopening the upper airway, implicating airway obstruction as a significant component of fentanyl-induced respiratory depression. Therefore, reversal of vocal cord closure appears to be the necessary precursor to the restoration of not only respiration, but also vascular autoregulation, a significant determinant of survival from fentanyl overdose.

pharmacology and toxicology↗

bioRxiv2025

Evaluating effects of elevated and accelerated NPQ relaxation on yield, physiology and transcription in soybean

Improving photosynthetic efficiency is proposed as a means of enhancing crop productivity under rising atmospheric CO2 concentrations ([CO2]). To assess whether additive gains can be realized from simultaneous improvements in light use-efficiency and carbon assimilation, we investigated the physiological and molecular responses to elevated CO2 (e[CO2]) of a transgenic soybean line (VPZ-34A) expressing the genes violaxanthin de-epoxidase (VDE), Photosystem II subunit S (PsbS) and zeaxanthin epoxidase (ZEP) from Arabidopsis thaliana (arabidopsis) (AtVPZ). Plants were grown at a free-air CO2 enrichment facility (SoyFACE) in 2021, with physiological and transcriptomic measurements collected during vegetative (V4-5) and reproductive stages (R5-6), then compared to final biomass and seed production parameters. VPZ-34A showed increased maximum quantum photosynthetic efficiency of photosynthesis ({varphi}PSIImax) under fluctuating light during vegetative stages, but no increase in maximum efficiency of carbon assimilation ({varphi}CO2, max), and no significant increase in seed or biomass related traits under ambient or e[CO2]. Transcriptome analysis showed the VPZ construct impacted a small number of genes, among them downregulation of a mitochondrial thioredoxin (Trx o1) and up-regulation of two AP2 transcription factors in VPZ lines may suggest alterations in redox balance and seed development. In conclusion, the improvements in {varphi}PSIImax and NPQ in VPZ-34A were unaffected by e[CO2] but didnt translate to stimulation of yield. Our data highlight the complexity of VPZ manipulation on plant performance and provide avenues for future research to optimize this strategy to improve crop yields.

plant biology↗

bioRxiv2025

Mapping high resolution, multidimensional phase diagrams of physiological protein condensates

Biomolecular condensates are membraneless compartments, crucial for organising and regulating diverse cellular processes. Current approaches to study condensate biology either use simplified recombinant protein systems with limited physiological relevance, or complex live-cell models with restricted experimental control and scalability. Here, we present ExVivo PhaseScan, a droplet microfluidics platform that couples mammalian lysate-based reconstitution with scalable analysis to generate high-resolution phase diagrams of physiological protein condensates. We apply this approach to study two complex multicomponent condensate systems, stress granules and nucleoli, and dissect the physicochemical interactions that influence their stability. We further developed a machine learning pipeline to analyse condensate morphology which we use to reveal how mutations in the ALS-linked protein FUS remodels condensate phase landscapes. We identify liquid-to-solid transitions of mutant FUS within stress granules and nucleoli, and show that these transitions can be reversed by RNA aptamer-based interventions. Together, these findings establish ExVivo PhaseScan as a versatile tool for dissecting the physicochemical and pathological regulation of condensates, with potential to inform therapeutic strategies for diseases driven by aberrant phase transitions.

biophysics↗

bioRxiv2025

Physiological Significance of Bacterial Mn(II) Oxidation

Bacterial oxidation of Mn(II) to Mn(III/IV) oxides is widespread in nature and proceeds markedly faster than abiotic oxidation. However, the physiological role of this process remains unclear. Building on recent evidence that environmental stress determines bacterial Mn(II)-oxidation activity, we used Pseudomonas putida KT2440--a known Mn(II)-oxidizing bacterium--to investigate the potential drivers and benefits of this reaction. Using RNA-seq, we observed up-regulation of starvation-related two-component system genes during Mn(II) oxidation, supporting the idea that nutrient limitation acts as a trigger. This led us to hypothesize that introducing an external antagonistic stressor could further accelerate the onset and rate of Mn(II) oxidation. To test this, we established a synthetic microbial community in which KT2440 was confronted with Pseudomonas aeruginosa PAO1, which possesses both contact-dependent and diffusible antagonistic systems. Across multiple assays measuring oxidation initiation time, manganese oxide accumulation, and bacterial survival, the presence of PAO1 significantly accelerated Mn(II) oxidation by KT2440. More importantly, Mn(II) oxidation strongly enhanced KT2440 survival under antagonistic pressure. Correlation analysis indicated a positive relationship between survival rate and oxidation intensity. Fluorescence microscopy and agent-based modeling further confirmed that this protective effect is contact-dependent. By integrating these results with earlier findings, we propose that the physiological significance of bacterial Mn(II) oxidation lies in enhancing the survival fitness of the oxidizer under stressful conditions.

microbiology↗

bioRxiv2025

Effects of cell growth and temperature on mitochondrial physiology of Drosophila melanogaster embryonic cell line

The fruit fly Drosophila melanogaster is a valuable model for studying cellular and metabolic processes conserved with mammals. Using its embryonic Schneider S2 cell line, commonly used for heterologous protein expression, we investigated how culture duration and slight temperature changes affect mitochondrial physiology via high-resolution respirometry. We assessed five mitochondrial bioenergetic parameters and two coupling parameters at early and late growth phases, and at two temperatures (26{degrees}C and 28{degrees}C). We observed that a moderate temperature increase coupled with late growth phase synergistically enhanced basal, OXPHOS, and leak respiration, with only minor impacts on mitochondrial coupling efficiency. Notably, spare and maximal respiratory capacities increased disproportionately with either cell growth progression or moderate temperature rise, suggestive of enhanced mitochondrial biogenesis. These results demonstrate that small temperature increases and cell maturation activate mitochondrial bioenergetic capacity through mechanisms consistent with mitochondrial biogenesis and functional remodeling. Such adaptations improve cellular metabolic resilience while maintaining energy conversion efficiency. These findings deepen understanding of mitochondrial plasticity in response to environmental and developmental signals. They may inform strategies to optimize mitochondrial physiology in various biological contexts, including aging, metabolic diseases, and stress adaptation.

biochemistry↗

bioRxiv2025

Bacterial strains in the human gut associate with host physiology

The human microbiota influences host physiology, yet much of its complexity lies beneath the species level. Here, we analyzed the intra-species genetic diversity of 936 gut bacteria across 24,997 individuals from three countries. Our findings show that highly abundant species exhibit greater strain stability, whereas low-abundance species display increased in-clonal mutations. Clonal strains are often mutually exclusive, while genetically variable strains tend to coexist. Strain turnover is associated with the presence of annotated chemotaxis and sporulation genes in reference genomes, whereas strain coexistence is associated with quorum sensing and secretion systems. Leveraging deep phenotypic data, we constructed an atlas detailing strain-level associations with diverse host physiological domains. For example, Phocaeicola vulgatus sub-types relate to host obesity, Lachnospira eligens to sleep, and Parabacteroides distasonis to iron hemostasis. This resource may guide personalized microbiome-based interventions to improve human health.

microbiology↗

bioRxiv2017

Massive Phenotypic Measurements Reveal Complex Physiological Consequences Of Differential Translation Efficacies

AO_SCPCAPBSTRACTC_SCPCAPControl of protein biosynthesis is at the heart of resource allocation and cell adaptation to fluctuating environments. One genes translation often occurs at the expense of anothers, resulting in global energetic and fitness trade-offs during differential expression of various functions. Patterns of ribosome utilization--as controlled by initiation, elongation and release rates--are central to this balance. To disentangle their respective determinants and physiological impacts, we complemented measurements of protein production with highly parallelized quantifications of transcripts abundance and decay, ribosome loading and cellular growth rate for 244,000 precisely designed sequence variants of an otherwise standard reporter. We find highly constrained, non-monotonic relationships between measured phenotypes. We show that fitness defects derive either from protein overproduction, with efficient translation initiation and heavy ribosome flows; or from unproductive ribosome sequestration by highly structured, slowly initiated and overly stabilized transcripts. These observations demonstrate physiological impacts of key sequence features in natural and designed transcripts.

synthetic biology↗

bioRxiv2018

Physiological motion of the carotid atherosclerotic plaque quantified using ultrasound B-Mode image analysis

BackgroundPhysical motion throughout the cardiac cycle may contribute to the rupture of the atherosclerotic carotid plaque, resulting in ischaemic stroke. The purpose of this study was to quantify the physiological motion of the atherosclerotic carotid plaque and to investigate any relationship between the quantified motion parameters and the degree of stenosis, greyscale plaque characteristics, and the presence of cerebrovascular symptoms.\n\nMethodsDisplacement, velocity and acceleration of 81 plaques (51% symptomatic, stenosis range 10%-95%) from 51 patients were measured using an automated system employing a block matching algorithm relative to the ultrasound probe and relative to the periadventitial tissues, over a mean duration of 5 cardiac cycles.\n\nResultsAveraged across all plaques, the displacement amplitude was 1.2 mm relative to the probe, and 0.35 mm relative to the periadventitial tissues. Maximum and mean plaque velocities were 4.7 and 1.3 mm/s relative to the ultrasound probe, and 2.4 and 0.70 mm/s relative to the periadventitial tissues. The corresponding acceleration magnitudes were 69 and 22 mm/s2 relative to the probe, and 57 and 18 mm/s2 relative to the periadventitial tissues. There were no significant differences in any of the motion parameters, with respect to the presence of cerebrovascular symptoms, and none of the parameters showed a statistically significant relationship to the degree of stenosis, and the greyscale plaque characteristics (p[≤]0.05). The technique used was able to detect plaque motion amplitudes above 50m.\n\nConclusionsThis study provides quantitative data on the physiological motion of the atherosclerotic carotid plaque in-vivo. No significant relationship was found between the measured motion parameters and the presence of cerebrovascular symptoms, the degree of stenosis, and the greyscale plaque characteristics.

biophysics↗

bioRxiv2018

A computational model to understand mouse iron physiology and diseases

It is well known that iron is an essential element for life but is toxic when in excess or in certain forms. Accordingly there are many diseases that result directly from either lack or excess of iron. Iron has also been associated with a wide range of other diseases and may have an important role in aging. Yet many molecular and physiological aspects of iron regulation have only been discovered recently and others are still awaiting elucidation. In the last 18 years, after the discovery of the hormone hepcidin, many details of iron regulation have become better understood and a clearer picture is starting to emerge, at least in qualitative terms. However there is still no good quantitative and dynamic description of iron absorption, distribution, storage and mobilization that agrees with the wide array of phenotypes presented in several iron-related diseases. The present work addresses this issue by developing a mathematical model of iron distribution in mice that was calibrated with existing ferrokinetic data and subsequently validated against data from a series of iron disorders, such as hemochromatosis, {beta}-thalassemia, atransferrinemia and anemia of inflammation. To adequately fit the ferrokinetic data required including the following mechanisms: a) the role of transferrin in deliving iron to tissues, b) the induction of hepcidin by high levels of transferrin-bound iron, c) the ferroportin-dependent hepcidin-regulated iron export from tissues, d) the erythropoietin regulation of erythropoiesis, and e) direct NTBI uptake by the liver. The utility of such a model to simulate disease interventions was demonstrated by using it to investigate the outcome of different schedules of transferrin treatment in {beta}-thalassemia. The present model is a successful step towards a comprehensive mathematical model of iron physiology incorporating cellular and organ level details.

systems biology↗

bioRxiv2018

Biophysical underpinning of astroglial physiology probed with realistic cell models

Electrically non-excitable astroglia take up neurotransmitters, buffer extracellular K+ and generate Ca2+ signals that release molecular regulators of neural circuitry. The underlying machinery remains enigmatic, mainly because the nanoscopic, sponge-like astrocyte morphology has been difficult to access experimentally or explore theoretically. Here, we have systematically evaluated the multi-scale morphology of protoplasmic astroglia to construct a realistic multi-compartmental cell model that can be biophysically interrogated in NEURON computational environment. This approach has been implemented as an astrocyte-model builder ASTRO. As a proof of concept, we explored a hippocampal astrocyte reconstructed in silico against a battery of physiological and imaging experiments. This exploration has unveiled some basic features of astroglial physiology inaccessible empirically, such as the characteristic length of membrane voltage propagation, membrane effects of local glutamate transport, spatiotemporal dynamics of intracellular K+ redistribution, key Ca2+ buffering properties, and some basic relationships between free Ca2+ dynamics and experimental readout of fluorescent Ca2+ indicators.

neuroscience↗

bioRxiv2018

Functional phenomics: An emerging field integrating high-throughput phenotyping, physiology, and bioinformatics

HighlightFunctional phenomics is an emerging field in plant biology that relies on high-throughput phenotyping, big data analytics, controlled manipulative experiments, and simulation modelling to increase understanding of plant physiology.\n\nAbstractThe emergence of functional phenomics signifies the rebirth of physiology as a 21st century science through the use of advanced sensing technologies and big data analytics. Functional phenomics highlights the importance of phenotyping beyond only identifying genetic regions because a significant knowledge gap remains in understanding which plant properties will influence ecosystem services beneficial to human welfare. Here, a general approach for the theory and practice of functional phenomics is outlined including exploring the phene concept as a unit of phenotype. The functional phenomics pipeline is proposed as a general method for conceptualizing, measuring, and validating utility of plant phenes. The functional phenomics pipeline begins with ideotype development. Second, a phenotyping platform is developed to maximize the throughput of phene measurements. A mapping population is screened measuring target phenes and indicators of plant performance such as yield and nutrient composition. Traditional forward genetics allows genetic mapping, while functional phenomics links phenes to plant performance. Based on these data, genotypes with contrasting phenotypes can be selected for smaller yet more intensive experiments to understand phene-environment interactions in depth. Simulation modeling can be used to understand the phenotypes and all stages of the pipeline feed back to ideotype and phenotyping platform development.

plant biology↗

bioRxiv2018

Evolutionarily conserved anatomical and physiological properties of olfactory pathway till fourth order neurons in a species of grasshopper (Hieroglyphus banian)

Olfactory systems of different species show variations in structure and physiology despite some conserved characteristics. We characterized the olfactory circuit of the grasshopper Hieroglyphus banian of family Acrididae (subfamily: Hemiacridinae) and compared it to a well-studied species of locust, Schistocerca americana (subfamily: Cyrtacanthacridinae), also belonging to family Acrididae. We used in vivo electrophysiological, immunohistochemical and anatomical (bulk tract tracing) methods to elucidate the olfactory pathway from the second order neurons in antennal lobe to the fourth order neurons in {beta}-lobe of H. banian.\n\nWe observe highly conserved anatomical and physiological characteristics till the fourth order neurons in the olfactory circuit of H. banian and S. americana, though they are evolutionarily divergent (~57 million years ago). However, we found one major difference between the two species-there are four antennal lobe tracts in H. banian while only one is reported in S. americana. Besides, we are reporting for the first time, a new class of bilateral neurons which respond weakly to olfactory stimuli even though they innervate densely downstream of Kenyon cells.

neuroscience↗

bioRxiv2018

Is physiological stress state reflected in acoustic structure of vocalizations? An experimental test in wild North American red squirrels

Acoustic signaling is an important means by which animals communicate both stable and labile characteristics. Although it is widely appreciated that vocalizations can convey information on labile state, such as fear and aggression, very few studies have experimentally examined the acoustic expression of short-term stress state. The transmission of such information about physiological state could have broad implications, potentially allowing other individuals to modify their behavior or life history traits in response to this public information. North American red squirrels (Tamiasciurus hudsonicus) produce vocalizations known as rattles that advertise territorial ownership. We examined the influence of changes in physiological stress state on rattle acoustic structure through the application of a stressor (trapping and handling the squirrels) and by provisioning squirrels with exogenous glucocorticoids (GCs). We characterized the acoustic structure of rattles emitted by these squirrels by measuring rattle duration, mean frequency, and entropy. Our results provide mixed evidence that rattles show a \"stress signature\". When squirrels were trapped and handled, they produced rattles that were longer in duration with a higher frequency and increased entropy. However, squirrels that were administered exogenous GCs had similar rattle duration, frequency, and entropy as squirrels that received control treatments and unmanipulated (unfed) squirrels. Our results indicate that short-term stress does affect the acoustic structure of vocalizations, but elevated circulating GC levels are not solely responsible for such changes.

animal behavior and cognition↗

bioRxiv2018

Physiological genomics of dietary adaptation in a marine herbivorous fish

Adopting a new diet is a significant evolutionary change and can profoundly affect an animals physiology, biochemistry, ecology, and its genome. To study this evolutionary transition, we investigated the physiology and genomics of digestion of a derived herbivorous fish, the monkeyface prickleback (Cebidichthys violaceus). We sequenced and assembled its genome and digestive transcriptome and revealed the molecular changes related to important dietary enzymes, finding abundant evidence for adaptation at the molecular level. In this species, two gene families experienced expansion in copy number and adaptive amino acid substitutions. These families, amylase, and bile salt activated lipase, are involved digestion of carbohydrates and lipids, respectively. Both show elevated levels of gene expression and increased enzyme activity. Because carbohydrates are abundant in the pricklebacks diet and lipids are rare, these findings suggest that such dietary specialization involves both exploiting abundant resources and scavenging rare ones, especially essential nutrients, like essential fatty acids.

genomics↗