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bioRxiv2021

Effect of exogenously applied alpha-tocopherol on vital agronomic, physiological and biochemical attributes of Lentil (Lens culinaris Medik.) under induced drought stress

Water being a vital part of cell protoplasm plays a significant role in sustaining life on earth; drastic changes in climatic condition leads to limit the availability of water and causing other environmental chaos. Alpha-tocopherol being a powerful antioxidant plays a vital role in scavenging the ill effects of oxidative stress. A pot experiment was conducted by exposing lentil cultivar (Punjab-2009) to varying levels of induced drought stress, sprinkled with -tocopherol 100, 200 and 300 mg/L. Induced water deficit stress conditions caused a pronounced decline in growth parameters including absolute growth rate (AGR), leaf area index (LAI), leaf area ratio (LAR), root shoot ratio (RSR), relative growth rate (RGR), chlorophyll a, b, total chlorophyll content, carotenoids and soluble protein content (SPC) which were significantly enhanced by exogenously applied -tocopherol. Moreover, a significant increase was reported in total proline content (TPC), soluble sugar content (SSC), glycine betaine (GB) content, endogenous tocopherol levels, ascorbate peroxidase (APX), catalase (CAT) peroxidase (POD) and superoxide dismutase (SOD) activities. On contrary, exogenously applied -tocopherol significantly reduced the concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2). In conclusion, it was confirmed that exogenously applied -tocopherol under induced drought stress regimes ameliorated drought stress tolerance potential of lentil cultivar to a great extent; by enhancing growth, physiological and biochemical attributes.

plant biology↗

bioRxiv2021

Aerobic growth physiology of Saccharomyces cerevisiae on sucrose is strain-dependent

Present knowledge on the quantitative aerobic physiology of the yeast Saccharomyces cerevisiae during growth on sucrose as sole carbon and energy source is limited to either adapted cells or to the model laboratory strain CEN.PK113-7D. To broaden our understanding of this matter and open novel opportunities for sucrose-based biotechnological processes, we characterized three strains, with distinct backgrounds, during aerobic batch bioreactor cultivations. Our results reveal that sucrose metabolism in S. cerevisiae is a strain-specific trait. Each strain displayed a distinct extracellular hexose concentration and invertase activity profiles. Especially, the inferior maximum specific growth rate (0.21 h-1) of the CEN.PK113-7D strain, with respect to that of strains UFMG-CM-Y259 (0.37 h-1) and JP1 (0.32 h-1), could be associated to its low invertase activity (0.04 to 0.09 U mgDM-1). Moreover, comparative experiments with glucose or fructose alone, or in combination, suggest mixed mechanisms of sucrose utilization by the industrial strain JP1, and points out the remarkable ability of the wild isolate UFMG-CM-259 to grow faster on sucrose than on glucose in a well-controlled cultivation system. This work hints to a series of metabolic traits that can be exploited to increase sucrose catabolic rates and bioprocess efficiency. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/432870v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@132c7a3org.highwire.dtl.DTLVardef@d0b790org.highwire.dtl.DTLVardef@c38ef4org.highwire.dtl.DTLVardef@de6bee_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2021

Multimodal characterization of Yucatan minipig behavior and physiology through maturation

Brain injuries that are induced by external forces are particularly challenging to model experimentally. In recent decades, the domestic pig has been gaining popularity as a highly relevant animal model to address the pathophysiological mechanisms and the biomechanics associated with head injuries. Understanding cognitive, motor, and sensory aspects of pig behavior throughout development is crucial for evaluating cognitive and motor deficits after injury. We have developed a comprehensive battery of tests to characterize the behavior and physiological function of the Yucatan minipig throughout maturation. Behavioral testing included assessments of learning and memory, executive functions, circadian rhythms, gait analysis, and level of motor activity. We applied traditional behavioral apparatus and analysis methods, as well as state-of-the-art sensor technologies to report on motion and activity, and artificial intelligent approaches to analyze behavior. We studied pigs from 16 weeks old through sexual maturity at 35 weeks old. The results show multidimensional characterization of minipig behavior, and how it develops and changes with age. This animal model may capitulate the biomechanical consideration and phenotype of head injuries in the developing brain and can drive forward the field of understanding pathophysiological mechanisms and developing new therapies to accelerate recovery in children who have suffered head trauma.

animal behavior and cognition↗

bioRxiv2021

Distribution, Epidemics dynamics and physiological races of wheat stem rust (Puccinia graminis f.sp. tritici Eriks and E. Henn) on irrigated wheat in the Awash River basin of Ethiopia

Wheat is one of the high value important major crops of the globe. However, wheat stem rust is considered one of the determinant threats to wheat production in Ethiopia and the globe. So this study was conducted with the objective to assess disease intensity, seasonal distribution dynamics, and genetic variability and to determine virulence spectrum of stem rust in the irrigated wheat areas of Ethiopia. A total of 137 wheat farms were evaluated from 2014/15 - 2019/20 in six districts of Awash River basin. Farm plots were assessed every 5 - 10 km interval with X fashion, and data on disease incidence, severity, and healthy plants were scored with diseased wheat plant samples collection for stem rust race analysis. The seasonal trend of wheat stem rust disease was also compared to see the future importance of the diseases. The result revealed that the prevalence, incidence, and severity of stem rust were significantly varied among the different districts and seasons in the two regions. The survey results also indicated that about 71.7% of the wheat fields were affected by stem rust during the 2018/19 growing season. The overall incidence and mean severity of the disease during the same season were 49.02% and 29.27%, respectively. During 2019/20 about 63.7% of the wheat fields were affected by stem rust, which, however, the incidence (30.97%) and severity (17.22%) were lower than the previous season. Although the seasonal disease distribution was decreased, its spatial distribution was expanding into Lower Awash. The physiological and the genetic race analysis identified four dominant races (TTTTF, TKTTF TKKTF, and TTKTF) during 2018/19 and additional race (TKPTF) during 2019/20. Thus races are highly virulent and affect most of the Sr genes except Sr - 31 and Sr - 24. TTTTF and TKKTF are the widest virulence spectrum which affects 90% of the Sr genes. Thus, it can be concluded that the spatial and seasonal distribution of the disease was expanding. Moreover, most of the races were similar with rain-fed production, and thus care must be given for effective management of the diseases to both agro-ecologies. Therefore, these findings provide inputs or insight for breeders to think about the breeding programs in their crossing lines and wheat producers to reduce the damage of the disease in the irrigated ecologies. ETHICAL STATEMENTThus, surveys were conducted with the lateral aim of rust epidemics early warning and monitoring support program in the Awash River basin. Samples for this study were collected from farmers fields of the irrigated production areas in the Awash River basin. The disease was an air-borne disease that is difficult to contain. Still, we give maximum care during surveying through spore-free through self-sanitation after Pgt infested field observation to minimize induced disease dissemination to the communities in the production areas that no specific permissions were required for these locations. Field sites are on public access, and P. graminis f. sp. tritici is already an air-born pathogen that doesnt need special protection kinds. This work was our study experience in the endeavor in irrigated wheat technology dissemination.

molecular biology↗

bioRxiv2021

Sexual selection affects the evolution of physiological and life history traits

Sexual selection and sexual conflict are expected to affect all aspects of the phenotype, not only traits that are directly involved in reproduction. Here, we show coordinated evolution of multiple physiological and life history traits in response to long-term experimental manipulation of the mating system in populations of Drosophila pseudoobscura. Development time was extended under polyandry relative to monogamy in both sexes, potentially due to higher investment in traits linked to sexual selection and sexual conflict. Individuals (especially males) evolving under polyandry had higher metabolic rates and locomotor activity than those evolving under monogamy. Polyandry individuals also invested more in metabolites associated with increased endurance capacity and efficient energy metabolism and regulation, namely lipid and glycogen. Finally, polyandry males were less desiccation- and starvation-resistant than monogamy males, suggesting trade-offs between resistance and sexually selected traits. Our results provide experimental evidence that mating systems can impose selection that influences the evolution of non-sexual phenotypes such as development, activity, metabolism, and nutrient homeostasis.

evolutionary biology↗

bioRxiv2021

Connectivity and Synaptic Physiology in the Mouse and Human Cortex

To elucidate cortical microcircuit structure and synaptic properties we present a unique, extensive, and public synaptic physiology dataset and analysis platform. Through its application, we reveal principles that relate cell type to synapse properties and intralaminar circuit organization in the mouse and human cortex. The dynamics of excitatory synapses align with the postsynaptic cell subclass, whereas inhibitory synapse dynamics partly align with presynaptic cell subclass but with considerable overlap. Despite these associations, synaptic properties are heterogeneous in most subclass to subclass connections. The two main axes of heterogeneity are strength and variability. Cell subclasses divide along the variability axis, while the strength axis accounts for significant heterogeneity within the subclass. In human cortex, excitatory to excitatory synapse dynamics are distinct from those in mouse and short-term plasticity varies with depth across layers 2 and 3. With a novel connectivity analysis that enables fair comparisons between circuit elements, we find that intralaminar connection probability among cell subclasses exhibits a strong layer dependence.These and other findings combined with the analysis platform create new opportunities for the neuroscience community to advance our understanding of cortical microcircuits.

neuroscience↗

bioRxiv2021

Differentiation of speech-induced artifacts from physiological high gamma activity in intracranial recordings

There is great interest in identifying the neurophysiological underpinnings of speech production. Deep brain stimulation (DBS) surgery is unique in that it allows intracranial recordings from both cortical and subcortical regions in patients who are awake and speaking. The quality of these recordings, however, may be affected to various degrees by mechanical forces resulting from speech itself. Here we describe the presence of speech-induced artifacts in local-field potential (LFP) recordings obtained from mapping electrodes, DBS leads, and cortical electrodes. In addition to expected physiological increases in high gamma (60-200 Hz) activity during speech production, time-frequency analysis in many channels revealed a narrowband gamma component that exhibited a pattern similar to that observed in the speech audio spectrogram. This component was present to different degrees in multiple types of neural recordings. We show that this component tracks the fundamental frequency of the participants voice, correlates with the power spectrum of speech and has coherence with the produced speech audio. A vibration sensor attached to the stereotactic frame recorded speech-induced vibrations with the same pattern observed in the LFPs. No corresponding component was identified in any neural channel during the listening epoch of a syllable repetition task. These observations demonstrate how speech-induced vibrations can create artifacts in the primary frequency band of interest. Identifying and accounting for these artifacts is crucial for establishing the validity and reproducibility of speech-related data obtained from intracranial recordings during DBS surgery.

neuroscience↗

bioRxiv2021

Sleep-dependent upscaled excitability and saturated neuroplasticity in the human brain: From brain physiology to cognition

Sleep strongly affects synaptic strength, making it critical for cognition, especially learning, and memory formation. Whether and how sleep deprivation modulates human brain physiology and cognition is not well understood. Here we examined how overnight sleep deprivation vs sufficient sleep affects (a) cortical excitability, as measured by transcranial magnetic stimulation (TMS), (b) inducibility of LTP-and-LTD-like plasticity via transcranial direct current stimulation (tDCS), and (c) learning, memory and attention. The results suggest that sleep deprivation upscales cortical excitability due to enhanced glutamate-related cortical facilitation and decreased and/or reversed GABAergic cortical inhibition. Furthermore, tDCS-induced LTP-like plasticity abolishes while LTD-like plasticity converts to excitatory LTP-like plasticity under sleep deprivation. This is associated with increased EEG theta activity, which is related to sleep pressure. Finally, we show that learning and memory formation, behavioral counterparts of plasticity, and working memory and attention, which rely on cortical excitability, are impaired during sleep deprivation. Our data suggest that upscaled brain excitability, and altered plasticity, due to sleep deprivation, are associated with impaired cognitive performance.

neuroscience↗

bioRxiv2021

Epigenomic signature of the progeroid Cockayne syndrome exposes distinct and common features with physiological ageing

Cockayne syndrome (CS) and UV-sensitivity syndrome (UVSS) are rare genetic disorders caused by mutation of the DNA repair and chromatin remodelling proteins CSA or CSB, but only CS patients display a progeroid and neurodegenerative phenotype. As epigenetic modifications constitute a well-established hallmark of ageing, we characterized genome-wide DNA methylation (DNAm) of fibroblasts from CS versus UVSS patients and healthy donors. The analysis of differentially methylated positions and regions revealed a CS-specific epigenetic signature, enriched in developmental transcription factors, transmembrane transporters, and cell adhesion factors. The CS-specific signature compared to DNAm changes in other progeroid diseases and regular ageing, identifyied commonalities and differences in epigenetic remodelling. CS shares DNAm changes with normal ageing more than other progeroid diseases do, and according to the methylation clock CS samples show up to 13-fold accelerated ageing. Thus, CS is characterized by a specific epigenomic signature that partially overlaps with and exacerbates DNAm changes occurring in physiological aging. Our results unveil new genes and pathways that are potentially relevant for the progeroid/degenerative CS phenotype.

molecular biology↗

bioRxiv2021

The zinc transporter ZnuABC is critical for the virulence of Chromobacterium violaceum and contributes to diverse zinc-dependent physiological processes

Chromobacterium violaceum is a ubiquitous environmental bacterium that causes sporadic life-threatening infections in humans. How C. violaceum acquires zinc to colonize environmental and host niches is unknown. In this work, we demonstrated that C. violaceum employs the zinc uptake system ZnuABC to overcome zinc limitation in the host, ensuring the zinc supply for several physiological demands. Our data indicated that the C. violaceum ZnuABC transporter is encoded in a zur-CV_RS15045-CV_RS15040-znuCBA operon. This operon was repressed by the zinc uptake regulator Zur and derepressed in the presence of the host protein calprotectin (CP) and the synthetic metal chelator EDTA. A {Delta}znuCBA mutant strain showed impaired growth under these zinc-chelated conditions. Moreover, the deletion of znuCBA provoked a reduction in violacein production, swimming motility, biofilm formation, and bacterial competition. Remarkably, the {Delta}znuCBA mutant strain was highly attenuated for virulence in an in vivo mouse infection model and showed a low capacity to colonize the liver, grow in the presence of CP, and resist neutrophil killing. Overall, our findings demonstrate that ZnuABC is essential for C. violaceum virulence, contributing to subvert the zinc-based host nutritional immunity.

microbiology↗

bioRxiv2021

Ovulation sources coagulation protease cascade and hepatocyte growth factor to support physiological growth and malignant transformation

The fallopian tube fimbrial epithelium (FTE), which is exposed to the follicular fluid (FF) contents of ovulation, is regarded as the main origin of ovarian high-grade serous carcinoma (HGSC). Previously, we found that growth factors in FF, such as IGF2, are responsible for the malignant transformation of FTE. However, ovulation is a monthly transient event, whereas carcinogenesis requires continuous, long-term exposure. Here, we found the transformation activity of FF sustained for more than 30 days after drainage into the peritoneal fluid (PF). Hepatocyte growth factor (HGF), activated through the ovulation injury-tissue factor-thrombin-HGFA-HGF cleavage cascade confers a sustained transformation activity to FTE, HGSC. Physiologically, the high reserve of the coagulation-HGF cascade sources a sustained level of HGF in PF, then to the blood circulation. This HGF axis promotes the growth of the corpus luteum and repair of tissue injury after ovulation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=172 SRC="FIGDIR/small/448625v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@13d26d3org.highwire.dtl.DTLVardef@1c00c35org.highwire.dtl.DTLVardef@1619373org.highwire.dtl.DTLVardef@117a24d_HPS_FORMAT_FIGEXP M_FIG C_FIG The fluid content of the ovulating ovarian follicle (follicular fluid [FF]) exerts a long-lasting transformation effect that is sustained after mixing with peritoneal fluid (PF). The coagulation protease cascade and hepatocyte growth factor (HGF) are responsible for the sustained activity. The high abundance of cascade proteins and pro-form HGF activator and HGF in FF/PF supports the constant supply of active-form HGF lasting for a whole month, covering the entire ovulation cycle. This sustained HGF activity promotes the proliferative repair of the ovarian surface and fallopian tube fimbrial epithelia as well as the growth of the corpus luteum. The same activity also inadvertently promotes the malignant transformation of the fimbrial epithelium, high-grade serous carcinoma, and epithelial ovarian cancer. In addition to the peritoneal cavity, ovulation sources HGF to blood circulation, which may serve an endocrine role. HIGHLIGHTO_LIOvulatory follicular fluid (FF) exerts a long-lasting transformation activity covering throughout the ovulation cycle. C_LIO_LIThe ovulation injury-coagulation proteases-hepatocyte growth factor (HGF) cascade is responsible for the sustained activity. C_LIO_LIOvulation sources HGF into the peritoneal cavity, then into the blood circulation. C_LIO_LIThis coagulation-HGF cascade promotes the transformation of fallopian tube epithelial cells and ovarian cancer cells. C_LIO_LIPhysiologically, it promotes the growth of the corpus luteum and injured epithelium after ovulation. C_LI

cancer biology↗

bioRxiv2021

A topographical and physiological exploration of C-tactile afferents and their response to menthol and histamine.

Numerous microneurography studies in the human peroneal nerve have suggested that CT afferents are lacking in the more distal parts of the limbs. Here we recorded from unmyelinated low-threshold mechanosensitive afferents in the peroneal and radial nerves, with the most distal receptive fields located on the proximal phalanx of the third finger for the superficial branch of the radial nerve, and near the lateral malleolus for the peroneal nerve. We found that the physiological properties with regard to conduction velocity and mechanical threshold, as well as their tuning to brush velocity, were similar in CT units across the antebrachial, radial and peroneal nerves. Moreover, we found that while CT afferents are readily found during microneurography of the arm nerves, they appear to be much more sparse in the lower leg compared to C nociceptors. We continued to explore CT afferents with regard to their chemical sensitivity and found that they could not be activated by topical application to their receptive field of either the cooling agent menthol or the pruritogen histamine. In light of previous studies showing the combined effects that temperature and mechanical stimuli have on these neurons, including a lack of responsiveness to heat, these findings add to the growing body of research suggesting that CT afferents constitute a unique class of sensory afferents with highly specialized mechanisms for transducing gentle touch.

neuroscience↗

bioRxiv2021

Supra-physiological levels of Gibberellins/DELLAs alter the patterning, morphology and abundance of root hairs in root tips of A. thaliana seedlings

In spite of the known role of gibberellins (GAs), and of their antagonistic proteins, the DELLAs, in leaf hair production, no investigations, however, have assessed their hypothetical function in the production of root hairs. To this aim, the effects of supra-physiological levels of GAs/DELLAs on the spatial patterning of gene expression of the root hair (CPC) and root non-hair (GL2, EGL3 and WER) epidermal cell fate markers, as well as on the distribution, morphology and abundance of root hairs, were studied in root tips of 5-day-old A. thaliana seedlings. Results showed that excessive levels of GAs/DELLAs impaired the spatial patterning of gene expression of the root hair/non-hair epidermal cell fate markers, as well as the arrangement, shape and frequency of root hairs, giving rise to ectopic hairs and ectopic non-hairs, two-haired cells, two-tipped hairs, branched hairs, longer and denser hairs near the root tip under excessive DELLAs, and shorter and scarcer hairs near the root tip under excessive GAs. However, when the gai-1 (GA-insensitive-1) DELLA mutant protein was specifically over-expressed at the root epidermis, no changes in the patterning or abundance of root hairs occurred. Thus, these results suggest that, in seedlings of A. thaliana, the GAs/DELLAs might have a role in regulating the patterning, morphology and abundance of root hairs by acting from the sub-epidermal tissues of the root.

plant biology↗

bioRxiv2021

Diversified physiological sensory input connectivity questions the existence of distinct classes of spinal interneurons in the adult cat in vivo

The spinal cord is engaged in all forms of motor performance but its functions are far from understood. Because network connectivity defines function, we explored the connectivity for muscular, tendon and tactile sensory inputs among a wide population of spinal interneurons in the lower cervical segments. Using low noise intracellular whole cell recordings in the decerebrated, nonanesthetized cat in vivo, we could define mono-, di-, trisynaptic inputs as well as the weights of each input. Whereas each neuron had a highly specific input, and each indirect input could moreover be explained by inputs in other recorded neurons, we unexpectedly also found the input connectivity of the spinal interneuron population to form a continuum. Our data hence contrasts with the currently widespread notion of distinct classes of interneurons. We argue that this suggested diversified physiological connectivity, which likely requires a major component of circuitry learning, implies a more flexible functionality. 1. Graphical Abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY 2. HighlightsO_LIIn vivo whole cell, intracellular recording of spinal interneurons. C_LIO_LIPatterns of input from Ia, Ib and cutaneous afferents is highly diversified. C_LIO_LILearning appears to be a defining factor of spinal interneuron connectivity. C_LI

neuroscience↗

bioRxiv2021

Isolation of wild yeasts from Olympic National Park and Moniliella megachiliensis ONP131 physiological characterization for beer fermentation

Thousands of yeasts have the potential for industrial application, though many were initially considered contaminants in the beer industry. However, these organisms are currently considered important components in beers because they contribute new flavors. Non-Saccharomyces wild yeasts can be important tools in the development of new products, and the objective of this work was to obtain and characterize novel yeast isolates for their ability to produce beer. Wild yeasts were isolated from environmental samples from Olympic National Park and analyzed for their ability to ferment malt extract medium and beer wort. Six different strains were isolated, of which Moniliella megachiliensis ONP131 displayed the highest levels of attenuation during fermentations. We found that M. megachiliensis could be propagated in common yeast media, tolerated incubation temperatures of 37{degrees}C and a pH of 2.5, and was able to grow in media containing maltose as the sole carbon source. Yeast cultivation was considerably impacted (p<0.05) by lactic acid, ethanol, and high concentrations of maltose, but ONP131 was tolerant to high salinity and hop acid concentrations. This is one of the first physiological characterizations of M. megachiliensis, which has potential for the production of beer and other fermented beverages.

microbiology↗

bioRxiv2021

Supra-physiological levels of gibberellins/DELLAs modify the root cell size/number and the root architecture in root tips of A. thaliana seedlings. Connections to the root hair patterning and abundance

A previous study (McCarthy-Suarez, 2021) showed that growing A. thaliana seedlings for 5 days under excessive levels of gibberellins (GAs)/DELLAs altered the arrangement, shape and frequency of root hairs in root tips. Because no changes in the distribution or number of root hairs occurred when the gai-1 (gibberellin-insensitive-1) DELLA was over-expressed at the root epidermis, it was concluded that the GAs/DELLAs might regulate the root hair patterning and abundance in A. thaliana seedlings by acting from the root sub-epidermal tissues. In the present study, microscopy analyses showed that excessive levels of GAs/DELLAs also modified the size and number of root tip cells in A. thaliana seedlings. While excessive DELLAs shortened and widened the root epidermal, cortical, endodermal and pericycle cells, excessive GAs, excepting the epidermal cells, generally narrowed them. However, no changes of root cell size occurred when gai-1 was over-expressed at the root epidermis. In addition, high levels of DELLAs often induced extra cells at the root epidermis, cortex, endodermis and pericycle, whereas high levels of GAs sometimes induced extra cells at the root cortex and pericycle. On the other hand, excessive levels of DELLAs enhanced the outgrowth of lateral roots in root tips, unlike excessive levels of GAs. Thus, the results of this study suggest that supra-physiological levels of GAs/DELLAs might modify the size/number of root tip cells by acting from the root sub-epidermal tissues. This, in turn, might impact on the patterning and abundance of root hairs and on the root architecture.

plant biology↗

bioRxiv2021

Physiological and Metabolomic Consequences of Reduced Expression of the Drosophila brummer Triglyceride Lipase

Disruption of lipolysis has widespread effects on intermediary metabolism and organismal phenotypes. Defects in lipolysis can be modeled in Drosophila melanogaster through genetic manipulations of brummer (bmm), which encodes a triglyceride lipase orthologous to mammalian Adipose Triglyceride Lipase. RNAi-mediated knock-down of bmm in all tissues or metabolic specific tissues results in reduced locomotor activity, altered sleep patterns and reduced lifespan. Metabolomic analysis on flies in which bmm is downregulated reveals a marked reduction in medium chain fatty acids, long chain saturated fatty acids and long chain monounsaturated and polyunsaturated fatty acids, and an increase in diacylglycerol levels. Elevated carbohydrate metabolites and tricarboxylic acid intermediates indicate that impairment of fatty acid mobilization as an energy source may result in upregulation of compensatory carbohydrate catabolism. bmm downregulation also results in elevated levels of serotonin and dopamine neurotransmitters, possibly accounting for the impairment of locomotor activity and sleep patterns. Physiological phenotypes and metabolomic changes upon reduction of bmm expression show extensive sexual dimorphism. Altered metabolic states in the Drosophila model are relevant for understanding human metabolic disorders, since pathways of intermediary metabolism are conserved across phyla.

genetics↗

bioRxiv2021

Maternal and paternal sugar consumption interact to modify offspring life history and physiology

Intergenerational effects on offspring phenotypes occur in response to variation in both maternal and paternal nutrition. Because the combined maternal and paternal effects are rarely considered together however, their relative contributions, and the capacity for interactions between parental diets to shape offspring life history and physiology are not understood. To address this, we altered sucrose levels of adult fruit flies (Drosophila melanogaster) prior to mating, across two generations, producing parent-parent and parent-offspring combinations that were either matched or mismatched in dietary sucrose. We then measured lifespan, fecundity, body mass, and triglyceride levels in parents and offspring. We reveal complex non-additive interactions, that involve diets of each parent and offspring to shape offspring phenotypes, but the effects were generally not consistent with an adaptive response to parental diet. Notably, we find that interacting parental flies (sires and dams) lived longer when their sucrose treatments were matched, but they produced shorter-lived offspring.

evolutionary biology↗