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Xia, Z.

Publications and source records attributed to Xia, Z..

At least 37 records · Page 2Linked to original sources

Cadmium-induced gut dysbiosis precedes the onset of hippocampus-dependent learning and memory deficits in mice

BackgroundCadmium (Cd) is a heavy metal recognized as a neurotoxicant. However, the mechanisms underlying its neurotoxicity remain poorly understood. The gut-brain axis, a bidirectional communication pathway between the central nervous system and the gut microbiome, has been linked to various neurological disorders. Because the gut microbiome is a known target of Cd, it is important to investigate whether the gut-brain axis mechanistically contributes to the Cd-induced neurotoxicity. ObjectiveIn our initial exploration of the role of the gut-brain axis in modulating Cd neurotoxicity on cognition, we investigated whether Cd exposure induces gut dysbiosis before the onset of cognitive deficits and explored the potential link between gut microbiome alterations and Cd-induced cognitive deficits. MethodsAdult male mice were exposed to 3 mg/L Cd via drinking water for nine weeks. Behavioral assessments were conducted throughout the exposure period to evaluate cognitive function. Fresh fecal pellets were collected weekly to monitor changes in the gut microbiome composition. The effects of Cd on the hippocampus and intestine were analyzed using transcriptomics and mass spectrometry (MS)-based metabolomics. ResultsCd exposure resulted in hippocampus-dependent learning and memory deficits, first observed at four weeks into exposure. RNA sequencing of the hippocampus at the terminal time point revealed reduced expression of genes involved in cognition and neuroinflammation in Cd exposed mice. Metagenomic shotgun sequencing showed that Cd-induced gut dysbiosis preceded the onset of cognitive impairments, with specific bacterial species associated with Cd-induced cognitive deficits. Furthermore, Cd exposure reduced the expression of genes involved in intestinal barrier integrity, increased inflammatory cytokines levels, and altered the levels of neuroactive microbial metabolites. ConclusionOur study is the first to show that Cd exposure triggers gut microbial shifts before the onset of cognitive deficits, accompanied by increased intestinal permeability and elevated proinflammatory biomarkers in both the intestine and brain at the terminal time point. These findings suggest a potential critical role of gut-brain axis in modulating Cd neurotoxicity and underscore the need for future research to elucidate the mechanistic involvement of gut microbiome as a potential target for mitigating Cd-induced cognitive decline.

systems biology↗

Pancreatic cancer-intrinsic HuR regulates the pro-tumorigenic properties of extracellular vesicles

Pancreatic ductal adenocarcinoma (PDAC) tumors contain chaotic vasculature that limits immune surveillance and promotes early events in the metastatic cascade. However, current antiangiogenic therapies have failed in PDAC, and thus, it remains important to uncover mechanisms by which cancer cells signal to endothelial cells to increase angiogenesis. Our lab has shown that the tumor-intrinsic RNA-binding protein HuR (ELAVL1) plays an important role re-shaping the tumor microenvironment (TME) by regulating the stability and translation of cytokine encoding transcripts. Herein, we demonstrate that PDAC-intrinsic HuR influences endothelial cell function in the TME via extracellular vesicle (EV) signaling, an underexplored signaling axis in tumor progression. We found that HuR knockout (KO) tumors have impaired growth in an immunocompetent mouse model, and that administering purified wildtype (WT) EVs can increase tumor growth. Further, we observed that PDAC EVs contain HuR-dependent mRNA and protein cargoes relating to endothelial cell function and angiogenesis. Treatment of endothelial cells with HuR WT EVs strongly increased the expression of genes involved in barrier function and endothelial cell development, and directly increased their migratory and tube forming functions. In an immunocompetent orthotopic mouse model of PDAC, we showed that HuR increases endothelial cell presence and sprouting, while decreasing ICAM-1 expression. Importantly, we found utilizing a genetic EV reporter, that decreased ICAM-1 within WT tumors occurs in endothelial cells that have imported PDAC EVs, suggesting that this signaling axis is directly modulating endothelial cell behavior in vivo. Collectively, our data reveal a new role of HuR in EV signaling to endothelial cells, promoting angiogenesis while restricting endothelial cell leukocyte trafficking behavior.

cancer biology↗

mRNA stability factor HuR promotes immune evasion in pancreatic ductal adenocarcinoma

The tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) is characterized by a limited infiltration of tumor-specific T cells and anti-tumor T cell activity. Extracellular factors in the PDAC TME have been widely reported to mediate immune suppression, but the contribution from tumor-intrinsic factors is not well understood. The RNA-binding protein, HuR (ELAVL1), is enriched in PDAC and negatively correlates with T cell infiltration. In an immunocompetent Kras-p53-Cre (KPC) orthotopic model of PDAC, we found that genetic disruption of HuR impaired tumor growth due to a novel role of HuR inducing T-cell suppression. Importantly, we found that HuR depletion in tumors enhanced both T cell number and activation states and diminished myeloid phenotypes by comprehensive spatial profiling of the PDAC TME. Mechanistically, HuR mediated the stabilization of mTOR pathway transcripts, and inhibition of mTOR activity rescued the impaired function of local T cells. Translating these findings, we demonstrated that HuR depletion sensitized PDAC tumors to immune checkpoint blockade, while isogenic, wildtype tumors are resistant. For the first time, we show that HuR facilitates tumor immune suppression in PDAC by inhibiting T cell infiltration and function and implicate targeting HuR as a potential therapeutic strategy in combination with immunotherapy. SIGNIFICANCEThis study identified a novel mechanism that HuR supports pancreatic tumor growth by restricting T cell infiltration, promoting immune evasion. Our work supports targeting strategies against HuR in PDAC with the goal of enhancing PDAC sensitivity to immune-based cancer therapies, such as checkpoint blockade and T cell transfer.

cancer biology↗

Deciphering single-cell heterogeneity and cellular ecosystem dynamics during prostate cancer progression

Prostate cancer (PC) progresses from benign epithelium through pre-malignant lesions, localized tumors, metastatic dissemination, and castration-resistant stages, with some cases exhibiting phenotype plasticity under therapeutic pressure. However, high-resolution insights into how cell phenotypes evolve across successive stages of PC remain limited. Here, we present the Prostate Cancer Cell Atlas (PCCAT) by integrating [~]710,000 single cells from 197 human samples covering a spectrum of tumor stages. This comprehensive analysis dissects the cellular landscape and characterizes key cell types and molecular features that associate with PC progression and prognosis. In malignant cells, we highlight a distinctive profile denoted by high Major Histocompatibility Complex (MHC) expression, low Androgen Receptor (AR) activity, and enhanced stemness programs associated with enzalutamide resistance. Moreover, we reveal several cell states strongly correlated with PC progression and adverse prognosis, including lineage plasticity-like malignant cells (LPCs), neuroendocrine tumor cells, pericytes, and matrix cancer-associated fibroblasts (mCAFs). Furthermore, we uncover shared cell states that underpin the immune suppressive tumor microenvironment in advanced PC, including activated regulatory T cells, exhausted CD8+ T cells, and SPP1-expressing macrophages. Lastly, we pinpoint a spatial niche composed of mCAFs and SPP1-expressing macrophages localized near the tumor boundary in aggressive PC, which correlates with poor prognosis. Overall, our work provides a valuable resource and offers deeper insights into the diverse cell states, dynamics, and functional characteristics involved in PC progression at single-cell resolution.

cancer biology↗

Establishment and Molecular Characterization of Patient-Derived Organoids for Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) exhibits substantial heterogeneity, both intra-tumoral and intertumoral, posing challenges in developing effective treatment methods. Existing in vitro models fail to simulate the inherent microenvironment and the cellular and mutational diversity of native tumors and require a prolonged generation time. To address this concern, we described an organoid culture method for patient-derived PCNSL organoids (CLOs) and evaluated them through extensive molecular characterization. These CLOs accurately mimicked the histological attributes, gene expression landscapes and mutational profiles of their original tumors through rigorous histopathological analysis, RNA sequencing and whole-exome sequencing. Notably, CLOs were generated within 2 weeks, demonstrating rapid development and reliability. Furthermore, therapeutic profiling was performed on three selected CLOs using four standard treatment drugs. High concordance was observed between the drug responses of patients and those observed in the CLOs, with specific sensitivity to ibrutinib and methotrexate and resistance to dexamethasone and rituximab. Taken together, these results emphasize that CLOs can effectively emulate the key characteristics of PCNSL, enhancing the understanding of the genetic landscape of this complex disease. CLOs provide a rapid and reliable platform for exploring individualized treatment strategies, potentially accelerating the transition of research findings to clinical practice.

cancer biology↗

Relation of CMV and brain atrophy to trajectories of immunosenescence in diverse populations

Immunosenescence (ISC), the aging of the immune system, has largely been studied in populations of European descent. Here, circulating immune cell cytometric data from African-American, Hispanic, and non-Hispanic White participants were generated. Known and novel age effects were identified using either a meta-analysis approach or a parallel genetic approach. Most results are consistent across the three populations, but some cell populations display evidence of heterogeneity, such as a PD-L1+CD56+ NK cell subset. The study estimated "Immunological Age" (IA) during physiologic aging. While we found no relation of IA to Multiple Sclerosis, IA is associated with entorhinal cortex atrophy, a presymptomatic feature of Alzheimers disease, linking neurodegeneration and peripheral immunity. ISC trajectories were also inferred, highlighting age, CMV status, and genetic ancestry as key influences. Our assessment offers reference ISC trajectories for personalization of assessments of immune function over the life course in diverse populations.

immunology↗

Stromal KITL/SCF promotes pancreas tissue homeostasis and restrains tumor progression

Components of normal tissue architecture serve as barriers to tumor progression. Inflammatory and wound-healing programs are requisite features of solid tumorigenesis, wherein alterations to immune and non-immune stromal elements enable loss of homeostasis during tumor evolution. The precise mechanisms by which normal stromal cell states limit tissue plasticity and tumorigenesis, and which are lost during tumor progression, remain largely unknown. Here we show that healthy pancreatic mesenchyme expresses the paracrine signaling molecule KITL, also known as stem cell factor, and identify loss of stromal KITL during tumorigenesis as tumor-promoting. Genetic inhibition of mesenchymal KITL in the contexts of homeostasis, injury, and cancer together indicate a role for KITL signaling in maintenance of pancreas tissue architecture, such that loss of the stromal KITL pool increased tumor growth and reduced survival of tumor-bearing mice. Together, these findings implicate loss of mesenchymal KITL as a mechanism for establishing a tumor-permissive microenvironment. Statement of significanceBy analyzing transcriptional programs in healthy and tumor-associated pancreatic mesenchyme, we find that a sub-population of mesenchymal cells in healthy pancreas tissue express the paracrine signaling factor KITL. Loss of mesenchymal KITL is an accompanying and permissive feature of pancreas tumor evolution, with potential implications for cancer interception.

cancer biology↗

The state-of-the-art machine learning model for Plasma Protein Binding Prediction: computational modeling with OCHEM and experimental validation

Plasma protein binding (PPB) is closely related to pharmacokinetics, pharmacodynamics and drug toxicity. Prediction of PPB is an alternative to experimental approaches that are known to be time-consuming and costly. Although there are various models and web servers for PPB prediction already available, they suffer from low prediction accuracy and poor interpretability, in particular for molecules with high values, and are most often not properly validated in prospective studies. Here, we carried out strict data curation, and applied consensus modeling to obtain a model with a coefficient of determination of 0.90 and 0.91 on the training set and the test set, respectively. This model was further validated in a prospective study to predict 63 poly-fluorinated and another 25 highly diverse compounds, and its performance for both these sets was superior to that of other previously reported models. To identify structural features related to PPB, we analyzed a model based on Morgan2 fingerprints and identified that features such as aromatic rings, halogen atoms, heterocyclic rings can discriminate high- and low-PPB molecules. In conclusion, we have established a PPB prediction model that showed state-of-the-art performance in prospective screening, which we have made publicly available in the OCHEM platform (https://ochem.eu/article/29). Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/603170v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@660730org.highwire.dtl.DTLVardef@61f81corg.highwire.dtl.DTLVardef@1e80d07org.highwire.dtl.DTLVardef@1af719a_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Altered liver metabolism post-wean abolishes efficacy of vitamin D for breast cancer prevention in a mouse model

Young women have increased risk of vitamin D deficiency, which may increase breast cancer incidence. Here, we assessed the anti-cancer efficacy of vitamin D in mouse models of young-onset breast cancer. In never-pregnant mice, vitamin D supplementation increased serum 25(OH)D and hepatic 1,25(OH)2D3, reduced tumor size, and associated with anti-tumor immunity. These anti-tumor effects were not replicated in a mouse model of postpartum breast cancer, where hepatic metabolism of vitamin D was suppressed post-wean, which resulted in deficient serum 25(OH)D and reduced hepatic 1,25(OH)2D3. Treatment with active 1,25(OH)2D3 induced hypercalcemia exclusively in post-wean mice, highlighting metabolic imbalance post-wean. RNAseq revealed suppressed CYP450 expression postpartum. In sum, we provide evidence that vitamin D anti-tumor activity is mediated through immunomodulatory mechanisms and is ineffective in the post-wean window due to altered hepatic metabolism. These findings have implications for suppressed xenobiotic metabolism in postpartum women beyond vitamin D. Statement of SignificanceIn a rodent model of postpartum breast cancer, weaning suppresses hepatic CYP450 activity and renders vitamin D supplementation ineffective, with implications for xenobiotic drug efficacy and safety. A tailored approach to therapy based on reproductive history is crucial for young breast cancer patients, and for healthcare strategies for postpartum women.

cancer biology↗

Androgen receptor activity inversely correlates with immune cell infiltration and immunotherapy response across multiple cancer lineages

There is now increasing recognition of the important role of androgen receptor (AR) in modulating immune function. To gain a comprehensive understanding of the effects of AR activity on cancer immunity, we employed a computational approach to profile AR activity in 33 human tumor types using RNA-Seq datasets from The Cancer Genome Atlas. Our pan-cancer analysis revealed that the genes most negatively correlated with AR activity across cancers are involved in active immune system processes. Importantly, we observed a significant negative correlation between AR activity and IFN{gamma} pathway activity at the pan-cancer level. Indeed, using a matched biopsy dataset from subjects with prostate cancer before and after AR-targeted treatment, we verified that inhibiting AR enriches immune cell abundances and is associated with higher IFN{gamma} pathway activity. Furthermore, by analyzing immunotherapy datasets in multiple cancers, our results demonstrate that low AR activity was significantly associated with a favorable response to immunotherapy. Together, our data provide a comprehensive assessment of the relationship between AR signaling and tumor immunity.

cancer biology↗

Biologically informed machine learning modeling of immune cells to reveal physiological and pathological aging process

The immune system undergoes progressive functional remodeling from neonatal stages to old age. Therefore, understanding how aging shapes immune cell function is vital for precise treatment of patients at different life stages. Here, we constructed the first transcriptomic atlas of immune cells encompassing human lifespan, ranging from newborns to supercentenarians, and comprehensively examined gene expression signatures involving cell signaling, metabolism, differentiation, and functions in all cell types to investigate immune aging changes. By comparing immune cell composition among different age groups, HLA highly expressing NK cells and CD83 positive B cells were identified with high percentages exclusively in the teenager (Tg) group, whereas CD4_CTL precursors were exclusively enriched in the supercentenarian (Sc) group. Notably, we found that the biological age (BA) of pediatric COVID-19 patients with multisystem inflammatory syndrome accelerated aging according to their chronological age (CA). Besides, we proved that inflammatory shift-myeloid abundance and signature correlate with the progression of complications in Kawasaki disease (KD). Finally, based on those age-related immune cell compositions, we developed a novel BA prediction model, PHARE (https://xiazlab.org/phare/), which applies to both scRNA-seq and bulk RNA-seq data. Overall, our study revealed changes in immune cell proportions and function associated with aging, both in health and disease, and provided a novel tool for successfully capturing features that accelerate or delay aging.

immunology↗

Insight into the gut virome in patients with multiple sclerosis

Multiple sclerosis (MS) is an autoimmune condition associated with dysbiosis in the bacterial element of microbiome, yet limited information exists regarding dysbiosis in the virome. In this study, we examined the virome in 20 relapsing-remitting MS (RRMS) patients and 22 healthy controls (HC). We extracted virus-like particles (VLP) genomic DNA through sequential filtration, followed by deep metagenomic sequencing approaches with and without multiple displacement amplification (MDA). We found significantly lower diversity in the gut virome of RRMS patients relative to HC, consistent across both sequencing methods. MDA method identified reduced relative abundance of Microviridae and Myoviridae bacteriophage, and eukaryotic virus such as Herpesviridae and Phycodnaviridae in RRMS patients compared to HC. Non-MDA methods showed reduction in relative abundance of Siphoviridae bacteriophage and eukaryotic viruses such as Ackermannviridae, Demerecviridae, Dicistroviridae, Herelleviridae, Mesnidovirineae in RRMS patients. Cluster analysis revealed that the whole virome family was dominated by Podoviridae and Siphoviridae clusters. Comparing dietary metadata between these clusters, RRMS patients in the Siphoviridae-dominated Cluster B showed significantly higher consumption of refined grains and salad dressings compared to those in the Podoviridae-dominated Cluster A. Correlation analysis between gut viruses and bacteria demonstrated that Siphoviridae exhibited positive correlations with many different bacterial genera. Conversely, Microviridae displayed negative correlations with many different bacterial genera. These findings underscore the alterations in viral diversity and taxonomic composition of the gut virome in RRMS patients. Our study represents the first step in understanding the gut virome in MS patients, providing a groundwork for future research on the role of the gut virome in the context of MS.

microbiology↗

Attila and Aetius on the roof: The succession phenomenon in the roof greening area of a primary school in Beijing during the lockdown period of the COVID-19

"Succession" refers to the process of certain species replacing others over time. It is of great significance for understanding the characteristics and evolution of ecosystems. This article compares the changes in school rooftop green areas before and after the COVID-19 epidemic (2019, 2023), and studies the situation of wild grass invading roofs during the three years of the epidemic, as well as the response of original rooftop plants to the invasion. The results showed that: [circled1] invasive weeds were concentrated in 2 families and 4 species, forming a population advantage in most of the invaded planting boxes; [circled2] The succession has had a significant impact on the roof greening area; [circled3] Among the two cultivated plants (Phedimus aizoon (PA) and Sedum sarmentosum (SS)), SS was greatly affected, with the community almost disappearing, while PA was almost unaffected.

ecology↗

Androgen blockade primes NLRP3 in macrophages to induce tumor phagocytosis

Immune-based therapies induce durable remissions in subsets of patients across multiple malignancies. However, there is limited efficacy of immunotherapy in metastatic castrate-resistant prostate cancer (mCRPC), manifested by an enrichment of immunosuppressive (M2) tumor- associated macrophages (TAM) in the tumor immune microenvironment (TME). Therefore, therapeutic strategies to overcome TAM-mediated immunosuppression are critically needed in mCRPC. Here we discovered that NLR family pyrin domain containing 3 (NLRP3), an innate immune sensing protein, is highly expressed in TAM from metastatic PC patients treated with standard-of-care androgen deprivation therapy (ADT). Importantly, ex vivo studies revealed that androgen receptor (AR) blockade in TAM upregulates NLRP3 expression, but not inflammasome activity, and concurrent AR blockade/NLRP3 agonist (NLRP3a) treatment promotes cancer cell phagocytosis by immunosuppressive M2 TAM. In contrast, NLRP3a monotherapy was sufficient to enhance phagocytosis of cancer cells in anti-tumor (M1) TAM, which exhibit high de novo NLRP3 expression. Critically, combinatorial treatment with ADT/NLRP3a in a murine model of advanced PC resulted in significant tumor control, with tumor clearance in 55% of mice via TAM phagocytosis. Collectively, our results demonstrate NLRP3 as an AR-regulated "macrophage phagocytic checkpoint", inducibly expressed in TAM by ADT and activated by NLRP3a treatment, the combination resulting in TAM-mediated phagocytosis and tumor control.

cancer biology↗

An Engineered 3D Co-culture Model of Primary Macrophages and Patient-Derived Tumour Cells to Explore Cellular Responses in the Graded Hypoxic Microenvironment of Pancreatic Cancer

In pancreatic ductal adenocarcinoma (PDAC), tumour associated macrophages (TAMs) are a heterogeneous immune cell population that interact with cancer cells to promote malignancy, chemo-resistance, and immunosuppression. Aside from TAMs, hypoxia is a prominent feature of PDAC that can rewire cells to survive and enhance malignancy in the tumour microenvironment (TME). Deciphering the interactions between macrophages, cancer cells and hypoxia could lead to the development of effective immune-targeted therapies for PDAC. However, there are only a few models that physiologically recapitulate the PDAC TME and allow for meaningful interrogation of cancer-immune cell interactions in hypoxia. Here, we develop a model of primary macrophages and PDAC patient organoid-derived cells by adapting TRACER, a paper-based, engineered 3D model that allows snapshot analysis of cellular response in hypoxia. In this study, we establish a direct co-culture method of primary macrophages and PDAC organoid cells in TRACER and demonstrate that TRACER co-cultures generate hypoxic gradients and show expected phenotypic responses to this hypoxic gradient. Moreover, we report for the first time in a human in vitro model that hypoxic macrophages exert a graded chemoprotective effect on gemcitabine-treated PDAC organoid cells, and that interactions between cancer cells and macrophages from the inner layers of TRACER indirectly attenuate the inflammatory response of donor-derived T-cells. Overall, the TRACER co-culture system is a novel, fully human 3D in vitro cancer-immune model for evaluating the response of macrophages and cancer cells in a hypoxic gradient.

bioengineering↗

Pan-genome and Haplotype Map of Cultivars and Their Wild Ancestors Provides Insights into Adaptive Evolution of Cassava (Manihot esculenta Crantz)

Cassava is the most important starch sources, a tropical model crop. We constructed nearly T2T genomes of cultivar AM560, wild ancestors FLA4047 and W14, pan-genome of 24 representatives and a clarified evolutionary tree with 486 accessions. Comparison of SVs and SNVs between the ancestors and cultivated cassavas revealed predominant expansion, contraction of genes and gene families. Significantly selective sweeping occurred in the cassava genomes in 122 footprints with 1,519 candidate domestication genes. We identified selective mutations in MeCSK and MeFNR3 promoting photoreaction associated with MeNADP-ME of C4 assimilation in modern cassava. Co-evolved retardation of floral primordia and initiation of storage roots arose from MeCOL5 mutants with altered bindings to MeFT1, MeFT2 and MeTFL2. MebHLHs evolved to regulate the biosynthesis, transport and endogenous remobilization of cyanogenic glucosides, with new functionalities of MeMATE1, MeGTR in selected sweet cassava. These findings enhanced comprehensive knowledge and database on the evolution and breeding of cassava. HIGHLIGHTSO_LIThree nearly T2T cassava genomes of cultivar AM560 and its wild ancestors FLA4047 and W14. C_LIO_LIA species-level cassava panSV haplotype map across 346,322 structural variations over 31,362 gene families and 96,032,008 SNPs and InDels variations globally and a clarified evolutionary tree with 486 accessions. C_LIO_LISelective mutations in MeCSK and MeFNR3 promoted photoreaction associated with MeNADP-ME of C4 assimilation shaped the C3-C4 intermediate photosynthesis of modern cassava. C_LIO_LICoevolution of floral primordia contrary to initiated storage root is pivotal for the domestication of cassava, and arose from MeCOL5 mutants altered the binding with MeFT1, MeFT2 (SP6A), and MeTFL2. C_LI

systems biology↗

Shape-changing electrode array for minimally invasive large-scale intracranial brain activity mapping

Large-scale brain activity mapping is important for understanding the neural basis of behaviour. Electrocorticograms (ECoGs) have high spatiotemporal resolution, bandwidth, and signal quality. However, the invasiveness and surgical risks of electrode array implantation limit its application scope. We developed an ultrathin, flexible shape-changing electrode array (SCEA) for large-scale ECoG mapping with minimal invasiveness. SCEAs were inserted into cortical surfaces in compressed states through small openings in the skull or dura and fully expanded to cover large cortical areas. MRI and histological studies on rats proved the minimal invasiveness of the implantation process and the high chronic biocompatibility of the SCEAs. High-quality micro-ECoG activities mapped with SCEAs from rodent brains during seizures and canine brains during the emergence period revealed the spatiotemporal organization of different brain states with resolution and bandwidth that cannot be achieved using existing noninvasive techniques. The biocompatibility and ability to map large-scale physiological and pathological cortical activities with high spatiotemporal resolution, bandwidth, and signal quality in a minimally invasive manner offer SCEAs as a superior tool for applications ranging from fundamental brain research to brain-machine interfaces.

neuroscience↗

Pan-genome analysis highlights the role of structural variation in the evolution and environmental adaptation of Asian honeybees

The Asian honeybee, Apis cerana, is an ecologically and economically important pollinator. Mapping its genetic variation is key to understanding population-level health, histories, and potential capacities to respond to environmental changes. However, most efforts to date were focused on single nucleotide polymorphisms (SNPs) based on a single reference genome, thereby ignoring larger-scale genomic variation. We employed long-read sequencing technologies to generate a chromosome-scale reference genome for the ancestral group of A. cerana. Integrating this with 525 resequencing datasets, we constructed the first pan-genome of A. cerana, encompassing almost the entire gene content. We found that 31.32% of genes in the pan-genome were variably present across populations, providing a broad gene pool for environmental adaptation. We identified and characterized structural variations (SVs) and found that they were not closely linked with SNP distributions, however, the formation of SVs was closely associated with transposable elements. Furthermore, phylogenetic analysis using SVs revealed a novel A. cerana ecological group not recoverable from the SNP data. Performing environmental association analysis identified a total of 44 SVs likely to be associated with environmental adaptation. Verification and analysis of one of these, a 330 bp deletion in the Atpalpha gene, indicated that this SV may promote the cold adaptation of A. cerana by altering gene expression. Taken together, our study demonstrates the feasibility and utility of applying pan-genome approaches to map and explore genetic feature variations of honeybee populations, and in particular to examine the role of SVs in the evolution and environmental adaptation of A. cerana.

genomics↗