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Hu, X.

Publications and source records attributed to Hu, X..

At least 235 records · Page 13Linked to original sources

Non-parametric GWAS: Another View on Genome-wide Association Study

Genome-wide association study (GWAS) is a fundamental step for understanding the genetic link to traits (phenotypes) of interest, such as disease, BMI and height. Typically, GWAS estimates the effect of SNP on the phenotype using a linear model by coding SNP as working code, {0, 1, 2}, according to the minor allele frequency. Looking inside the linear model, we find that the coding strategy of SNP plays a key role in detecting SNPs contributed to the phenotype. Specifically, a partial mismatch between the order of the working code and that of the underlying true code will lead to false negatives, which has been ignored for a long time. Motivated by this phenomenon, we propose an indicator of possible false negatives and several non-parametric GWAS methods independent of coding strategy. Results from both simulations and real data analysis show the advantages of new methods in identifying significant loci, indicating their important complementary role in GWAS.

genetics↗

Aryl hydrocarbon receptor utilises cellular zinc signals to maintain the gut epithelial barrier

Both zinc and plant-derived ligands of the aryl hydrocarbon receptor (AHR) are dietary components which regulate intestinal epithelial barrier function and protect against Inflammatory Bowel Disease (IBD)1,2. Here, we explore whether zinc and AHR pathway are linked using a mouse IBD model with follow-on studies on human and mouse ileum organoids. Our data demonstrate that AHR regulates cellular zinc uptake, and that zinc is an integral part of AHR signalling processes. We show that dietary supplementation in mice with the plant-derived AHR ligand precursor, indole-3-carbinol (I3C), offers a high level of protection against dextran sulfate sodium induced IBD while protection fails in mice with AHR deleted in the intestinal epithelium. AHR agonist treatment is also ineffective in mice with a nutritional zinc deficiency. Experiments in the human Caco-2 cell line and ileum organoids showed that AHR activation increases total cellular zinc and cytosolic free Zn2+ concentrations through transcriptional upregulation of several SLC39 zinc importers. As a consequence, genes for tight junction (TJ) proteins were upregulated in a zinc-dependent manner involving zinc inhibition of signalling to NF-{kappa}B and attenuated degradation of TJ proteins through zinc inhibition of calpain activity. Thus, our data indicate that AHR activation by plant-derived dietary ligands improves gut barrier function via zinc-dependent cellular pathways, suggesting that combined dietary supplementation with AHR ligands and zinc might be effective in preventing and treating inflammatory gut disorders.

cell biology↗

Naturally occurring Alzheimer's disease in rhesus monkeys

Alzheimers disease (AD) is the most common neurodegenerative disease. To date, its cause is unclear and there are no effective treatments or preventive measures. Despite there are accumulating evidences for the existence of AD pathological hallmarks in the brain of aging rhesus monkeys, it remains a mainstream notion that monkeys do not develop AD naturally. This is an important issue because it will determine how we use monkeys in AD studies. To settle down this issue, a group (n=10) of aged rhesus monkeys 26 years old or above went through a systematic AD screening procedure in this study. Three of these monkeys showed severe memory impairments (SMI) after evaluated with a classic working memory test. Further behavioral testing revealed that the SMI monkeys also exhibited apathy-like behavior, which is another core AD clinical symptom. In addition to the cognitive deficits, two of the three SMI monkeys developed all of the three AD pathological hallmarks, including neurofibrillary tangles, senile plaques and neuronal loss. According to the diagnostic criteria of human AD, the two SMI monkeys were clearly naturally occurring AD monkeys. These results suggest that AD is not a uniquely human disease and monkeys have great potential for the development of much needed etiological AD models, which are vital for better understanding of developmental process of AD and the base of identification of early diagnostic biomarkers and effective therapeutic targets of AD.

neuroscience↗

Quartet DNA reference materials and datasets for comprehensively evaluating germline variants calling performance

Current methods for evaluating the accuracy of germline variant calls are restricted to easy-to-detect high-confidence regions, thus ignoring a substantial portion of difficult variants beyond the benchmark regions. We established four DNA reference materials from immortalized cell lines derived from a Chinese Quartet including parents and monozygotic twins. We integrated benchmark calls of 4.2 million small variants and 15,000 structural variants from multiple platforms and bioinformatic pipelines for evaluating the reliability of germline variant calls inside the benchmark regions. The genetic built-in-truth of the Quartet family design not only improved sensitivity of benchmark calls by removing additional false positive variants with apparently high quality, but also enabled estimation of the precision of variants calls outside the benchmark regions. Batch effects of variant calling in large-scale DNA sequencing efforts can be effectively identified with the concurrent use of the Quartet DNA reference materials along with study samples, and can be alleviated by training a machine learning model with the Quartet reference datasets to remove potential artifact calls. Matched RNA and protein reference materials were also established in the Quartet project, thereby enabling benchmark calls constructed from DNA reference materials for evaluation of variants calling performance on RNA and protein data. The Quartet DNA reference materials from this study are a resource for objective and comprehensive assessment of the accuracy of germline variant calls throughout the whole-genome regions.

bioinformatics↗

ARTseq-FISH reveals position-dependent fate decisions driven by cell cycle changes

Differences in gene-expression profiles between individual cells can give rise to distinct cell fate decisions. Yet how localisation on a micropattern impacts initial changes in mRNA, protein, and phosphoprotein abundance remains unclear. To identify the effect of cellular position on gene expression, we developed a scalable antibody and mRNA targeting sequential fluorescence in situ hybridization (ARTseq-FISH) method capable of simultaneously profiling mRNAs, proteins, and phosphoproteins in single cells. We studied 67 (phospho-)protein and mRNA targets in individual mouse embryonic stem cells (mESCs) cultured on circular micropatterns. ARTseq-FISH reveals relative changes in both abundance and localization of mRNAs and (phospho-)proteins during the first 48 hours of exit from pluripotency. We confirm these changes by conventional immunofluorescence and time-lapse microscopy. Chemical labelling, immunofluorescence, and single-cell time-lapse microscopy further show that cells closer to the edge of the micropattern exhibit increased proliferation compared to cells at the centre. Together these data suggest that while gene expression is still highly heterogeneous position-dependent differences in mRNA and protein levels emerge as early as 12 hours after LIF withdrawal.

systems biology↗

Human XIRP1 is a macrophage podosome protein utilized by Listeria for actin-based motility

Actin is integral to eukaryotic physiology as a biomechanical polymer and as a structural barrier for cell-autonomous defense against infection. Some microbial pathogens exploit the actin cytoskeleton, however, to evade cell-autonomous immunity. Subversion of actin to enter host cells and for actin-based motility are often employed by intracellular pathogens to spread from cell-to-cell. Using RNA-sequencing and computational data mining, we identify the host actin-binding protein XIRP1 as commonly induced during infection. XIRP1 is expressed by fibroblasts and macrophages in response to immune cytokines such as interferon-gamma (IFN-{gamma}) and infection with bacteria such as Listeria, Shigella, and Salmonella. Confocal and super-resolution structured illumination microscopy (SIM) found XIRP1 localizes to fibroblast focal adhesions and macrophages podosomes. Within human macrophages, XIRP1 is recruited to cytosolic Listeria monocytogenes in an ActA-dependent manner as it replicates and uses actin-based motility for host cell escape. Chromosomal removal of XIRP1 in mice impaired this dissemination and rendered them more resistant to Listeria infection than C57BL/6NJ wildtype controls in vivo. We propose that professional cytosolic pathogens like Listeria can co-opt XIRP1 to escape the hostile intracellular environment of IFN-{gamma}-activated macrophages as part of the host-pathogen arms race during cell-autonomous immunity.

immunology↗

Analysis of a genetic region affecting mouse body weight

Genetic factors affect an individuals risk of developing obesity, but in most cases each genetic variant has a small effect. Discovery of genes that regulate obesity may provide clues about its underlying biological processes and point to new ways the disease can be treated. Pre-clinical animal models facilitate genetic discovery in obesity because environmental factors can be better controlled compared to the human population. We studied inbred mouse strains to identify novel genes affecting obesity and glucose metabolism. BTBR T+ Itpr3tf/J (BTBR) mice are fatter and more glucose intolerant than C57BL/6J (B6) mice. Prior genetic studies of these strains identified an obesity locus on chromosome 2. Using congenic mice, we found that obesity was affected by a ~316 kb region, with only two known genes, pyruvate dehydrogenase kinase 1 (Pdk1) and integrin alpha 6 (Itga6). Both genes had mutations affecting their amino acid sequence and reducing mRNA levels. Both genes have known functions that could modulate obesity, lipid metabolism, insulin secretion and/or glucose homeostasis. We hypothesized that genetic variation in or near Pdk1 or Itga6 causing reduced Pdk1 and Itga6 expression would promote obesity and impaired glucose tolerance. We used knockout mice lacking Pdk1 or Itga6 fed an obesigenic diet to test this hypothesis. Under the conditions we studied, we were unable to detect an individual contribution of either Pdk1 or Itga6 to body weight. However, we identified a previously unknown role for Pdk1 in cardiac lipid metabolism providing the basis for future investigations in that area.

physiology↗

Single molecule long-read real-time amplicon-based sequencing of CYP2D6: a proof-of-concept with hybrid haplotypes

CYP2D6 is a widely expressed human xenobiotic metabolizing enzyme, best known for its role in the hepatic phase I cytochrome P450 enzyme system, where it metabolizes [~]20% of medications. It is also expressed in other organs including the brain, where its potential role in physiology and mental health traits and disorders is under further investigation. Owing to the presence of homologous pseudogenes in the CYP2D locus and transposable repeat elements in the intergenic regions, the gene encoding the CYP2D6 enzyme, CYP2D6, is one of the most hypervariable known human genes - with more than 165 core haplotypes. Haplotypes include structural variants, with a subtype of these known as hybrid haplotypes or fusion genes comprising part of CYP2D6 and part of its adjacent pseudogene, CYP2D7. The fusion genes are particularly challenging to identify. High fidelity (HiFi) single molecule real-time (SMRT) long-read sequencing can cover whole CYP2D6 haplotypes in a single continuous sequence, and is therefore ideal for structural variant detection. In addition, it is highly accurate and suitable for novel haplotype identification, which is necessary as new CYP2D6 haplotypes are continuously being discovered, and many more likely remain to be identified in relatively understudied populations such as Indigenous Peoples. The aim of the present work was to develop an efficient and accurate HiFi SMRT amplicon-based method capable of detecting the full range of CYP2D6 haplotypes including fusion genes. We report proof-of-concept for 24 amplicons including three positive controls, aligned to fusion gene haplotypes, with prior cross-validation data. Amplicons with CYP2D7-D6 fusion genes, including positive controls, aligned to the *13 subhaplotypes predicted (*13F, *13A2) with 100% accuracy, with the exception of one that aligned at 99.9%. Alignment of the *68 was 100% and above 99.9% to the CYP2D6*68 partial sequences EU5300606 and JF307779, respectively. The best alignments for the remaining CYP2D6-2D7 fusion genes were [≥]99.7% (to 3 significant figures). Lower percentage alignment for CYP2D6-2D7 fusion genes may reflect imperfect PCR optimization and/or the possibility that we may have haplotypes not yet in public databases. Further work on these is in progress. Moreover, we have adapted this method for non-hybrid haplotypes. This technique could therefore suffice for the characterization of the full range of CYP2D6 haplotypes. The method that we have developed could be extended to other complex loci and to other species in a multiplexed high throughput assay.

genomics↗

The Chromosome-based Genome of Paspalum vaginatum Provides New Insights into Salt-stress Adaptation

Salinization is increasingly a major factor limiting production worldwide. Revealing the mechanism of salt tolerance could help to create salt-tolerant crops and improve their yields. We reported a chromosome-scale genome sequence of the halophyte turfgrass Paspalum vaginatum, and provided structural evidence that it shared a common ancestor with Z. mays and S. bicolor. A total of 107 P. vaginatum germplasms were divided into two groups (China and foreign group) based on the re-sequenced data, and the grouping findings were consistent with the geographical origin. Genome-wide association study (GWAS) of visually scored wilting degree and withering rates identified highly significant QTL on chromosome 6. Combination with RNA-seq, we identified a significantly up-regulated gene under salt stress, which encodes High-affinity K+ Transporter 7 (PvHKT7), as strong candidates underlying the QTL. Overexpression of this gene in Arabidopsis thaliana significantly enhanced salt tolerance by increasing K+ absorption. This study adds new insights into salt-stress adaptation of P. vaginatum and serve as a resource for salt-tolerant improvement of grain crops.

genomics↗

Stability of SARS-CoV-2 in cold-chain transportation environments and the efficacy of disinfection measures

Cold-chain environment could extend the survival duration of SARS-CoV-2 and increases the risk of transmission. However, the effect of clod-chain environmental factors and packaging materials on SARS-CoV-2 stability and the efficacy of intervention measures to inactivate SARS-CoV-2 under cold-chain environment remains uncertain. This study aimed to unravel cold-chain environmental factors that preserved the stability of SARS-CoV-2 and disinfection measures against SARS-CoV-2 under the cold-chain environment. The spike gene of SARS-CoV-2 isolated from Wuhan hu-1 was used to construct the SARS-CoV-2 pseudovirus and used as model of the SARS-CoV-2 virus. The decay rate of SARS-CoV-2 pseudovirus in the cold-chain environment, various types of packaging material surfaces i.e., PE plastic, stainless steel, Teflon and cardboard, and in frozen seawater was investigated. The influence of LED visible light(wavelength 450 nm-780 nm) and airflow movement on the stability of SARS-CoV-2 pseudovirus at -18{degrees} C were subsequently assessed. The results show that SARS-CoV-2 pseudovirus decayed more rapidly on porous cardboard surface compared with the non-porous surfaces including PE plastic, stainless steel and Teflon. Compared with 25{degrees} C, the decay rate of SARS-CoV-2 pseudovirus was significantly lower at low temperature. Seawater preserved viral stability both at -18{degrees} C and repeated freeze-thawing cycles compared with deionized water. LED visible light illumination and airflow movement environment at -18{degrees} C reduced the SARS-CoV-2 pseudovirus stability. In conclusion, our results indicate cold-chain temperature and seawater as risk factors for SARS-CoV-2 transmission and LED visible light illumination and airflow movement as possible disinfection measures of SARS-CoV-2 under the cold-chain environment. ImportanceIt is widely recognized that low temperature is a condition for maintaining virus vitality, and cold-chain transportation spreads the events of the SARS-CoV-2 were reported. This study provides that the decay rate of the SARS-CoV-2 pseudovirus at low temperatures varies on different packaging materials, and salt ions present in frozen foods such as seafood may protect virus survival. These results provide evidence for the possibility of SARS-CoV-2 transmission through cold-chain transport and also suggest the importance for disinfection of items. However, the commonly used disinfection methods of ultraviolet radiation and chemical reagents are generally not suitable for the disinfection of frozen food. Our study shows LED visible light illumination and airflow movement as possible disinfection measures of SARS-CoV-2 under the cold-chain environment. This has implications for reducing the long-distance transmission of the virus through cold-chain transportation.

microbiology↗

Serum response factor reduces gene expression noise and confers cell state stability

The role of serum response factor (Srf), a central mediator of actin dynamics and mechanical signaling, in cell identity regulation is debated to be either a cell identity stabilizer or destabilizer. We thus investigated the role of Srf in cell fate stability using mouse pluripotent stem cells, one of the very few cell types that can tolerate null Srf. Despite the fact that serum-containing cultures yield heterogeneous gene expression, deletion of Srf in mouse pluripotent stem cells leads to further exacerbated cell state heterogeneity. The exaggerated heterogeneity is not only detectible as increased lineage priming, but also as the 2C-like cell state. Thus, pluripotent cells explore more variety of cellular states in both directions of development surrounding naive pluripotency, a behavior that is constrained by Srf. These results support that Srf functions as a cell state stabilizer, providing rationale for its functional perturbation in cell fate engineering and pathological intervention.

cell biology↗

Updating memories of unwanted emotions during human sleep

Post-learning sleep contributes to memory consolidation. Yet, it remains contentious whether sleep affords opportunities to modify or update emotional memories, such as those people would prefer to forget. Here we attempted to update memories during sleep using spoken positive emotional words paired with cues to recent memories for aversive events. Affect updating using positive words during human non-rapid-eye-movement (NREM) sleep, compared with using neutral words instead, reduced negative affect judgments in post-sleep tests, suggesting that the recalled events were perceived as less aversive. EEG analyses showed that emotional words modulated theta and spindle/sigma activity. Specifically, to the extent that theta power was larger for the positive word than for the following memory cue, participants judged the memory cues less negatively. Moreover, to the extent that sigma power was larger for the emotional word than for the following memory cue, participants showed higher forgetting of unwanted memories. Notably, when the onset of individual positive word coincided with the upstate of slow oscillations, a state characterized by increased cortical excitability during NREM sleep, affective updating was more successful. In sum, the affect content of memories was altered via strategic spoken words presentations during sleep, in association with theta power increases and slow-oscillation upstates. These findings offer novel possibilities for modifying unwanted memories during sleep, without requiring conscious confrontations with aversive memories that people would prefer to avoid.

neuroscience↗

The thermodynamic state of aerobic glycolytic flux plays a critical role in stabilizing aerobic glycolytic flux of cancer cells

Inhibition of aerobic glycolysis (AG) is a strategy for cancer treatment, but its clinical translation has not been successful, suggesting that the mechanism underlying the inhibition of AG is not completely understood. We introduce thermodynamic state of AG (TSAG) into AG flux control, which refers the actual change of Gibbs free energy ({Delta}G) of reactions along the pathway. By using PKM2 knockdown and knockout models, we found that TSAG is resistant to PKM2 perturbation and it can effectively counteract the inhibitory effect of PKM2 perturbation on AG flux. Moreover, we deciphered the interrelationship between TSAG, AG rate, intermediate concentrations, and PK activity, revealed that TSAG is a system property of AG independent of cancer cells pathophysiological features and it plays important roles in stabilizing AG flux responding to perturbation. We propose that both inhibition of glycolytic enzyme and disruption of TSAG are required for effective AG inhibition.

cancer biology↗

Nonlinear effect of light intensity on normal axial development of rhesus monkeys

PurposeTo investigate the effects of different indoor lighting intensity (500 lx, 750 lx and 1,000 lx) on normal ocular axial length growth by using juvenal rhesus monkeys. MethodsTwenty-four juvenile monkeys were exposed continuously to normal intensity light (NIL, 500 lx, n=16), medium intensity light (MIL, 750 lx, n=8) and high intensity light (HIL, 1 000 lx, n=8), with a same CCT value (about 3000 K) for 246 days. Axial length, anterior chamber depth, corneal curvature radius were measured at about a monthly interval. ResultsAfter 246 days of light exposure, the growth of axial length of the MIL group (750 lx) were 0.151 {+/-} 0.081 mm and 0.139 {+/-} 0.070 mm in the right and left eyes, respectively, and significantly larger in comparison with the NIL group (500lx, OD: 0.068 {+/-} 0.055 mm, OS: 0.074 {+/-} 0.057 mm) and the HIL group (1000lx,OD:0.063 {+/-} 0.093 mm, OS: 0.084 {+/-} 0.052 mm) monkeys. This effect was stable and robust during the whole experimental period. ConclusionThe effects of different intensity lighting on normal ocular axial development was not linear as most people currently think. We must be cautious when it comes to elevate light intensity in classrooms. Whether this conclusion is correct under lights of other CCT value needs further study.

developmental biology↗

The domain-separation low-dimensional language network dynamics in the resting-state support the flexible functional segregation and integration during language and speech processing

Modern linguistic theories and network science propose that the language and speech processing is organized into hierarchical, segregated large-scale subnetworks, with a core of dorsal (phonological) stream and ventral (semantic) stream. The two streams are asymmetrically recruited in receptive and expressive language or speech tasks, which showed flexible functional segregation and integration. We hypothesized that the functional segregation of the two streams was supported by the underlying network segregation. A dynamic conditional correlation approach was employed to construct frame-wise time-varying language networks and investigate the temporal reoccurring patterns. We found that the time-varying language networks in the resting-state robustly clustered into four low-dimensional states, which dynamically reconfigured following a domain-separation manner. Spatially, the hub distributions of the first three states highly resembled the neurobiology of primary auditory processing and lexical-phonological processing, motor and speech production processing, and semantic processing, respectively. The fourth state was characterized by the weakest functional connectivity and subserved as a baseline state. Temporally, the first three states appeared exclusively in limited time bins ([~]15%), and most of the time (> 55%), the language network kept inactive in state 4. Machine learning-based dFC-linguistics prediction analyses showed that dFCs of the four states significantly predicted individual linguistic performance. These findings suggest a domain-separation manner of language network dynamics in the resting-state, which forms a dynamic "meta-networking" (network of networks) framework. HighlightsO_LIThe time-varying language network in the resting-state is robustly clustered into four low-dimensional states. C_LIO_LISpatially, the first three dFC states are cognitively meaningful, which highly resemble the neurobiology of primary auditory processing and lexical-phonological representation, speech production processing, and semantic processing, respectively. C_LIO_LITemporally, the first three states appeared exclusively in limited time bins ([~]15%), and most of the time (> 55%), the language network kept inactive in state 4. C_LIO_LIA dynamic "meta-networking" framework of language network in the resting-state is proposed. C_LI

neuroscience↗

A Parabrachial to Hypothalamic Neurocircuit Mediates Defensive Behavior

Defensive behaviors are critical for animals survival. Both the paraventricular nucleus of the hypothalamus (PVN) and the parabrachial nucleus (PBN) have been shown to be involved in defensive behaviors. However, whether there are direct connections between them to mediate defensive behaviors remains unclear. Here, by retrograde and anterograde tracing, we uncover that cholecystokinin (CCK)-expressing neurons in the lateral PBN (LPBCCK) directly project to the PVN. By in vivo fiber photometry recording, we found that LPBCCK neurons actively respond to various threat stimuli. Selective photoactivation of LPBCCK neurons promotes aversion and defensive behaviors. Conversely, photoinhibition of LPBCCK neurons attenuates rat or looming stimuli-induced flight responses. Optogenetic activation of LPBCCK axon terminals within the PVN or PVN glutamatergic neurons promote defensive behaviors. Whereas chemogenetic and pharmacological inhibition of local PVN neurons prevent LPBCCK-PVN pathway activation-driven flight responses. These data suggest that LPBCCK neurons recruit downstream PVN neurons to actively engage in flight responses. Our study identifies a previously unrecognized role for the LPBCCK-PVN pathway in controlling defensive behaviors.

neuroscience↗

Intermittent fasting mitigates cognitive deficits in Alzheimer's disease via the gut-brain axis

Intermittent fasting (IF) is suggested to mitigate cognitive impairment in Alzheimers disease (AD). We detailed the effects of IF in AD development and assessed the contribution of the gut microbiota-metabolite-brain axis in promoting the effects of fasting. A 16-week IF regimen significantly improved spatial memory and cognitive function in AD transgenic mice; this improvement was accompanied by decreased A{beta} accumulation and suppression of neuroinflammation. IF reshaped the microbiota and beneficially altered the microbial metabolites related to cognitive function. Multi-OMICs integration demonstrated a strong connection between IF induced changes in hippocampus gene expression, the composition of the gut microbes, and the serum metabolites beneficial for cognitive function. Removal of gut microbes with antibiotics abolished the neuroprotective effects of IF. These findings suggest new avenues for therapy and nutritional intervention to prevent the development of AD and other neurodegenerative diseases.

animal behavior and cognition↗

Sex differences in islet stress responses support female beta cell resilience

ObjectivePancreatic {beta} cells play a key role in glucose homeostasis; dysfunction of this critical cell type causes type 2 diabetes (T2D). Emerging evidence points to sex differences in {beta} cells, but few studies have examined male-female differences in {beta} cell stress responses and resilience across multiple contexts, including diabetes. Here, we address the need for high-quality information on sex differences in {beta} cell/islet gene expression and function using both human and rodent samples. MethodsWe compared {beta} cell gene expression and insulin secretion in donors living with T2D to non-diabetic donors in both males and females. In mice, we generated a well-powered islet RNAseq dataset from 20-week-old male and female siblings with equivalent insulin sensitivity. Because on our unbiased analysis of gene expression pointed to sex differences in endoplasmic reticulum (ER) stress response, we subjected islets isolated from age-matched male and female mice to thapsigargin treatment and monitored protein synthesis, cell death, and {beta} cell insulin production and secretion. Transcriptomic and proteomic analyses were used to characterize sex differences in islet responses to ER stress. ResultsOur single-cell analysis of human {beta} cells revealed sex-specific changes to gene expression and function in T2D, correlating with more robust insulin secretion in islets isolated from female donors living with T2D compared to male T2D donors. In mice, RNA sequencing revealed differential enrichment of unfolded protein response pathway-associated genes, where female islets showed higher expression of genes linked with protein synthesis, folding, and processing. This differential expression was biologically significant, as female islets were more resilient to ER stress induction with thapsigargin. Specifically, female islets maintained better insulin secretion and showed a distinct transcriptional response under ER stress compared with males. ConclusionsOur data demonstrate that physiologically significant sex differences in {beta} cell gene expression exist in both humans and mice, and that female {beta} cells maintain better insulin production and secretion across multiple physiological and pathological contexts.

cell biology↗