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Biology subjects

Qi, D.

Publications and source records attributed to Qi, D..

At least 19 recordsLinked to original sources

Distinct extracellular matrix states uncouple collagen accumulation from pathological fibrosis in Duchenne muscular dystrophy

Fibrosis severity is routinely inferred from collagen abundance, although whether collagen quantity determines pathological fibrosis remains unclear. In Duchenne muscular dystrophy (DMD), chronic muscle injury and inflammation drive extracellular matrix accumulation, making these processes difficult to disentangle. We exploit sarcospan overexpression in mdx mice, a model of DMD (mdxTG), which improves membrane integrity and muscle function despite persistent matrix remodeling. mdxTG muscle accumulates more collagen than mdx yet lacks its dense macrophage-rich scars. Matrisome proteomics and spatial transcriptomics reveal compositionally and spatially distinct matrix states, while decellularized mdxTG matrix protects myotubes from membrane damage relative to mdx matrix. Despite these differences, both dystrophic matrices remain stiff and induce nuclear YAP in fibro-adipogenic progenitors. Verteporfin suppresses collagen production and reduces fibrosis in vivo, while nuclear YAP is increased in FAPs from patients with DMD. Thus, collagen abundance alone does not define pathological fibrosis; matrix organization, biological activity, and mechanosignaling distinguish functionally distinct fibrotic states.

physiology↗

ERK signaling integrates multiple mechanisms to drive cortical evolutionary expansion

A critical first step in human evolutionary divergence from chimpanzees and other primates is the production of greatly increased numbers of cortical pyramidal neurons during development and over evolutionary time. This expansion underpins the enlarged human cerebral cortex and, consequently, higher-order cognition and consciousness. However, the cellular and molecular mechanisms driving this progressive increase in cortical neuron number remain incompletely understood. Here we show that elevated ERK signaling in human cortical radial glia (RGs), relative to mouse RGs, arises from evolutionary changes in the developmental expression of existing shared genes. Using the Emx1-Cre line to overexpress MEK1DD, a constitutively active mutant of rat MAP2K1, we found that enhanced ERK signaling in mouse cortical RGs upregulates cAMP-PKA signaling, along with promoting self-renewal, expanding the RG pool, and accelerating cell cycle progression. Conversely, overexpression of PKA signaling in mouse cortical RGs via in utero electroporation of constitutively active PRKACA mutants (L206R or W196G) reduces ERK activity, prolongs the cell cycle, suppresses SHH-SMO and YAP/TAZ pathway activity, and blocks ependymal gliogenesis. Together, our results demonstrate that ERK and PKA signaling in cortical RGs engage a dynamic balance of synergistic and antagonistic interactions. This interplay couples evolutionarily enhanced ERK and PKA activities to increased cortical RG numbers, prolonged cell cycle progression, and an extended neurogenic period, which collectively culminate in a marked increase in neuronal production. We conclude that heightened ERK pathway activity in cortical RGs serves as a central driver of progressive neocortical expansion across mammalian evolution. Significance StatementThe human brains extraordinary cognitive abilities stem from a dramatic increase in cortical neuron numbers during evolution. This study reveals that enhanced ERK signaling in human cortical radial glia neural stem cells, relative to other primates, is a key driver of this expansion. By manipulating this pathway in mice, we demonstrate that ERK coordinates multiple mechanisms--including self-renewal, cell cycle acceleration, and a dynamic interplay with PKA signaling--to boost neuronal output. These findings identify a core molecular axis underlying mammalian cortical evolution and provide a framework for understanding how the human cortex acquired its unique size and, consequently, its remarkable complexity.

developmental biology↗

Deformability screening identifies NUDT5 as a mediator of cellular mechanobiology

How cells deform, sense, and respond to mechanical cues drives physiological and disease processes ranging from development to cancer metastasis; however, unbiased approaches to identify mechanical mediators are lacking. We screened 1280 compounds to identify modulators of cancer cell deformability using a cellular filtration assay and identified 92 compounds that significantly reduced deformability of ovarian cancer cells; top hits also reduced migration and invasion. Connectivity mapping of the top 21 compounds identified NUDT5 (Nudix hydrolase 5) as a predicted mechanical mediator; transcriptomic analyses implicated NUDT5 in mechanobiology and metabolic processes. We confirmed that NUDT5 mediates intracellular ATP and cellular mechanical behaviors, including morphology and deformability. In ovarian cancer, increased NUDT5 levels were associated with higher tumor stage and worse patient survival; NUDT5 inhibition reduced migration and colony formation in vitro and peritoneal tumor burden in mice. These findings establish deformability-based screening as a platform for discovering mechanical mediators and identify NUDT5 as a therapeutic target in ovarian cancer. TeaserScreening cells based on deformability provides an unbiased approach to identify NUDT5 as a mediator of cell mechanics

cell biology↗

Biocontrol efficiency and mechanism of novel Streptomyces luomodiensis SCA4-21 against banana Fusarium wilt

The soil-borne fungi Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) causes banana Fusarium wilt, which seriously threats global banana production. Biocontrol has been considered viable alternative method to manage banana Fusarium wilt. In previous study, we found that novel S. luomodiensis SCA4-21 exhibited antifungal activity. Here, we revealed that the extracts of strain SCA4-21 significantly inhibited the growth of Foc TR4 hyphae and spore germination, severely disrupting the ultrastructure of Foc TR4 hyphal cells and spore morphology. These extracts also exhibited broad-spectrum antifungal activity against eight other phytopathogenic fungi. Furthermore, we demonstrated that strain SCA4-21 produce 32 volatile organic compounds, including five antifungal compounds. In a pot experiment, we discovered that the inoculation of strain SCA4-21 significantly inhibited the infection of Foc TR4 in banana seedling corms, achieving a biocontrol efficiency of 59.3%, and promoted the growth of banana seedlings. Additionally, this inoculation significantly enhanced the abundances of beneficial bacterial genera Streptomyces, Bacillus, Sphingomonas, and Massilia, as well as fungal genera Mortierella, Purpureocillium, Gibellulopsis, and Xenomyrothecium, while significantly reduced the abundances of pathogenic bacteria genus Pantoea and fungal genus Fusarium, in the banana rhizosphere soil. Moreover, the inoculation of strain SCA4-21 significantly increased the enrichment of pathways such as carbohydrate metabolism, amino acid metabolism, and metabolism of terpenoids and polyketides. Therefore, we postulated that strain SCA4-21 may synergistically combat banana Fusarium wilt by producing antifungal compounds and enriching beneficial bacteria and fungi. Our findings present a promising biocontrol agent for the management of banana Fusarium wilt. IMPORTANCEBanana (Musa spp.) is one of the most popular fruit crops and the fourth largest food crop in developing countries within tropical and subtropical regions. However, the emergence and rapid spread of strain Foc TR4 seriously hinder the development of banana industry. Currently, there is no effective control measure available. Biological control holds potential due to its safety and effectiveness. Here, we found that the extracts of S. luomodiensis SCA4-21 exhibited significant inhibitory effects on the hyphal growth and spore germination of Foc TR4, as well as severe destructive effects on its cell morphology and ultrastructure, and broad-spectrum antifungal activity. We also discovered that the inoculation of strain SCA4-21 significantly inhibited the infection of Foc TR4 in banana seedling corms, reduced the incidence index of banana Fusarium wilt, promoted the growth of banana seedlings, and enhances beneficial microbes and metabolic pathways, suggesting that strain SCA4-21 is a promising biocontrol agent.

physiology↗

CAMKV Kinase Signaling Is a Novel Therapeutic Avenue with Prognostic Relevance in Neuroblastoma

Neuroblastoma (NB) can be a highly aggressive malignancy in children. However, the precise mechanisms driving NB tumorigenesis remain elusive. This study revealed the critical role of CREB phosphorylation in NB cell proliferation. By employing a CRISPR-Cas9 knockout screen targeting calcium/calmodulin-dependent protein kinase (CaMK) family members, we identified the CaM kinase-like vesicle-associated (CAMKV) protein as a kinase that mediates direct phosphorylation of CREB to promote NB cell proliferation. CAMKV was found to be a transcriptional target of MYCN/MYC in NB cells. CAMKV knockout and knockdown effectively suppressed NB cell proliferation and tumor growth both in vitro and in vivo. Bioinformatic analysis revealed that high CAMKV expression is significantly correlated with poor patient survival. High-risk NB frequently had high CAMKV protein levels by Immunohistochemical staining. Integrated transcriptomic and proteomic analyses of CAMKV knockdown cells unveiled downstream targets involved in CAMKV-regulated phosphorylation and signaling pathways, many of which are linked to neural development and cancer progression. We identified small molecule inhibitors targeting CAMKV and further demonstrated the efficacy of one inhibitor in suppressing NB tumor growth and prolonging the survival of mice bearing xenografted tumors. These findings reveal a critical role for CAMKV kinase signaling in NB growth and identified CAMKV kinase as a potential therapeutic target and prognostic marker for patients with NB.

cancer biology↗

The Lateral Ganglionic Eminence Does Not Generate Cortical Oligodendrocytes

The emergence of myelinating oligodendrocytes represents a pivotal developmental milestone in vertebrates, given their capacity to ensheath axons and facilitate the swift conduction of action potentials. It is widely accepted that cortical oligodendrocyte progenitor cells (OPCs) arise from medial ganglionic eminence (MGE), lateral/caudal ganglionic eminence (LGE/CGE) and cortical radial glial cells (RGCs). Here, we used two different fate mapping strategies to challenge the established notion that the LGE generates cortical OPCs. Furthermore, we used a Cre/loxP-dependent exclusion strategy to reveal that the LGE/CGE-derived OPCs are minimal. Additionally, we showed that specifically eliminating MGE-derived OPCs leads to a significant reduction of cortical OPCs. Together, our findings indicate that the contribution of OPCs from LGE/CGE is minimal, contrary to previous beliefs. These findings provide a new view of the developmental origins of cortical OPCs and a valuable foundation for future research on both normal development and oligodendrocyte-related disease.

developmental biology↗

Systems genetics identifies the association between Enc1 and cognitive function in the hippocampus

Ectodermal-Neural Cortex 1 (ENC1) is expressed in multiple regions of the brain, including the hippocampus. However, knowledge about its function has been well explored only in the context of peroxidative stress and cancer. In this study, we investigated the association of hippocampal Enc1 with cognitive function in BXD mice. We performed Pearson correlation, phenotype-wide association analysis (PheWAS), expression-Based PheWAS, pathway enrichment, and protein interaction networks on Enc1 and BXD phenotypes/transcriptome of the hippocampus, and the results indicated that Enc1 is inextricably linked to cognitive performance. In addition, we found that most of the Enc1 co-expressed genes were highly expressed in GABAergic neuronal cells. Expression quantitative trait loci analysis indicated that Enc1 was cis-regulated in the hippocampus of mice as well as human. Genome-wide association analysis revealed ENC1 to be significantly associated with cognitive-related traits, including age-related cognitive changes etc. In conclusion, our findings demonstrated that Enc1 is involved in cognitive functions mainly in hippocampal GABAergic neuronal cells through neurogenesis, synaptic signaling, and CGMP-PKG signaling pathways, and interacts with the neurological function-related genes.

genetics↗

Study on the preparation of bovine milk exosomes and the stability of lyophilized powder

Bovune milk exosomes (MK-exo) have bioactive effects on the health of consumers and can also serve as excellent drug delivery vehicles. However, long-term preservation and transportation remain major challenges at present. In this report, high-quality MK-exo are prepared on a large scale. We then developed a lyophilization method belonging to MK-exo, and performed acceleration and long-term stability experiments on the lyophilized MK-exo to evaluate the effect of lyophilization. The results showed that the lyophilized MK-exo can be stored at room temperature for at least 3 months and 2-8{degrees}C for 15 months. These findings provide data support for further understanding of the properties and applications of MK-exo.

bioengineering↗

Genome-wide Perturbation Analysis Screening System for Exosomes-Related Genes Based on the CRISPR/Cas9 Platform

As reported previously, exosomes have significant impacts on the physiological and pathological state in vivo. Exosomes have been extensively studied as a drug delivery carrier and some exosomes drugs have been undergoing clinical research. The mechanisms of exosome production, transport, and secretion remain to be studied in depth. Thus, here, we developed a novel CRISPR-UMI-based gene screening system, with which we can reveal the exosomes biogenesis, transport, and uptake mechanisms on a genome-wide scale. This system consists of two parts: one is a gene knockout component; the other part is a unique molecular identifiers (UMI) labeling component that can label the exosomes produced by the knockout cells, in which each sgRNA corresponds to a specific UMI. In this way, by detecting the UMI loaded in the exosomes, we can trace the knockout gene. In this study, we first verified the function of each component using plasmids and lentiviruses respectively. Next, we simulated the infection of cells with lentiviral libraries using a single lentivirus to validate the functionality of the screening system. Finally, we constructed a CRISPR-UMI-based library targeting 15 genes (genes with clear effects on exosomes biogenesis) to further validate the reliability of the screening system. The development of this screening system is of indispensable importance for the in-depth study of the mechanisms of exosome production and secretion, as well as for the improvement of exosomes production and the advancement of exosomes industrialization.

bioengineering↗

Analysis of the heterogeneity and complexity of murine extraorbital lacrimal gland via single-cell RNA sequencing

PurposeThe lacrimal gland is essential for maintaining ocular surface health and avoiding external damage by secreting the aqueous layer of the tear film. However, a healthy lacrimal glands inventory of cell types and heterogeneity remains understudied. MethodsHere, 10X genome-based single-cell RNA sequencing was used to generate an unbiased classification of cellular diversity in the extraorbital lacrimal gland (ELG) of C57BL/6J mice. From 48,077 high-quality cells, an atlas of cell heterogeneity was produced, and cell types were defined by classic marker genes. The possible functions of these cells and the pseudotime trajectories for certain cell populations were analyzed through bioinformatics. In addition, a preliminary analysis of the cell-cell communication network in ELG was performed. ResultsOver 41 subclasses of cells were identified, including 9 kinds of glandular epithelial cells, 7 kinds of fibroblasts, 10 kinds of myeloid-derived immune cells, at least 10 kinds of lymphoid-derived immune cells, 3 kinds of vascular-associated cell subsets, and 2 kinds of Schwann cells. Analysis of cell-cell communication networks revealed that innate lymphoid cells were closely associated with other cells. ConclusionsThis study provides the first comprehensive transcriptome atlas and related database of mouse ELG. This resource can aid in a deeper understanding of lacrimal gland biology and pathophysiology of its related diseases.

bioinformatics↗

A novel purity analysis method of bovine milk-derived exosomes by two-dimensional ultra-performance liquid chromatography

Exosomes have been implicated in many biological processes as intercellular communication carriers. Because exosomes are increasingly explored as natural vehicles for cell and gene therapies, and drug delivery applications, it is critical to have high-quality samples. Protein:particle ratio, ELISA, western blotting, polymerase chain reaction, and size-exclusion high-performance liquid chromatography are the main methods that have been extensively applied to analyze exosomes purity in recent years. However, there is currently no well-established method that is convenient for routine quality analysis of small-size impurities in exosomes samples. Here, a size-exclusion high-performance liquid chromatography (SE-HPLC), an ion-exchange high-performance liquid chromatography (IEX-HPLC), and a novel two-dimensional high-performance liquid chromatography (2D-HPLC) method were used to detect the purity of bovine milk-derived exosomes with different processes of exosome isolation in detail. The results showed that the 2D-HPLC method could enhance the accuracy of detecting exosomal purity with higher precision and accuracy of instrumental, reduced personal error and experimental cost, shortened analysis time greatly, and more automation. The 2D-HPLC method is rapid, exhibits high selectivity, and has good sensitivity, thus making it well-suited for application in the pharmaceutical and toxicological analysis of exosomes.

biochemistry↗

An oral vaccine for SARS-CoV-2 RBD mRNA-bovine milk-derived exosomes induces a neutralizing antibody response in vivo

The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19) has presented numerous challenges to global health. The vaccines, including lipid-based nanoparticle mRNA, inactivated virus and recombined protein, have been used to prevent SARS-CoV-2 infections in clinics and are immensely helpful against the epidemic. Here, we first present an oral mRNA vaccine based on bovine milk-derived exosomes (milk-exos), which encodes the SARS-CoV-2 receptor binding domain (RBD) as an immunogen. The results indicated that RBD mRNA delivered by milk-derived exosomes can produce secreted RBD peptide in 293 cells in vitro and stimulated neutralizing antibodies against RBD in mice. These results indicated that bovine milk-derived exosome-based mRNA vaccine could serve as a new strategy for preventing SARS-CoV-2 infection. Meanwhile, it also can work as a new oral delivery system for mRNA. One Sentence SummaryOral SARS-CoV-2 mRNA vaccine based on bovine milk-derived exosomes can stimulate neutralizing antibodies in mice.

immunology↗

Single-molecule imaging with cell-derived nanovesicles reveals early binding dynamics at a cyclic nucleotide-gated ion channel

Ligand binding to membrane proteins is critical for many biological signaling processes. However, individual binding events are rarely directly observed, and their asynchronous dynamics are occluded in ensemble-averaged measures. For membrane proteins, single-molecule approaches that resolve these dynamics are challenged by dysfunction in nonnative lipid environments, lack of access to intracellular sites, and costly sample preparation. Here, we introduce an approach combining cell-derived nanovesicles, microfluidics, and single-molecule fluorescence colocalization microscopy to track individual binding events at a cyclic nucleotide-gated TAX-4 ion channel critical for sensory transduction. Our observations reveal dynamics of both nucleotide binding and a subsequent conformational change likely preceding pore opening. We further show that binding of the second ligand in the tetrameric channel is less cooperative than previously estimated from ensemble-averaged binding measures. This approach is broadly applicable to studies of binding dynamics for proteins with extracellular or intracellular domains in native cell membrane.

biophysics↗

Comprehensive and Integrated Genomic Characterization of Human Immunome in Cancer

Genetic alterations in immune-related pathways are common hallmarks of cancer. However, to realize the full potential of immunotherapy, a comprehensive understanding of immune networks and how mutations impact network structure and functional output across cancer types is instrumental. Herein we systematically interrogated somatic mutations that could express neoantigens and alter immune responses in cancer patients compared to wild-type controls. To do so, we developed a network-based immunogenomics model (NIPPER) with scoring systems to prioritize critical genes and mutations eliciting differential HLA binding affinity and alternate responses to immunotherapy. These mutations are enriched in essential protein domains and often alter tumor infiltration by immune cells, affecting T cell receptor repertoire and B cell clonal expansion. Furthermore, we devised an interactome network propagation framework integrated with drug associated gene signatures to identify potential immunomodulatory drug candidates. Together, our systems-level analysis results help interpret the heterogeneous immune responses among patients, and serve as a resource for future functional studies and targeted therapeutics. SignificanceCancer cells induce specific immune-related pathway perturbations by mutations, transcriptional dysregulation, and integration of multi-omics data can help identify critical molecular determinants for effective targeted therapeutics.

immunology↗

Systematic characterization of somatic mutation-mediated microRNA regulatory network perturbations

Somatic mutations are a major source of cancer development. Many driver mutations have been identified in protein coding regions. However, the function of mutations located in microRNAs (miRNAs) and their target binding sites along the human genome remains largely unknown. Here, we built comprehensive cancer-specific miRNA regulatory networks across 30 cancer types to systematically analyze the effect of mutations on miRNA related pathways. 3,518,261 mutations from 9,819 samples were mapped to miRNA-gene interactions (mGI), and mutations in miRNAs versus in their target genes show a mutually exclusive pattern in almost all cancer types. Using a linear regression method, we further identified 89 driver mutations in 14 cancer types that can significantly perturb miRNA regulatory networks. We find that driver mutations play their roles by altering RNA binding energy and the expression of target genes. Finally, we demonstrate that mutated driver gene targets are significantly down-regulated in cancer and function as tumor suppressors during cancer progression, suggesting potential miRNA candidates with significant clinical implications. We provide this data resource (CanVar-mGI) through a user-friendly, open-access web portal. Together, our results will facilitate novel non-coding biomarker identification and therapeutic drug design.

bioinformatics↗

Transcriptional Profiling Reveals the Transcription Factor Networks Regulating the Survival of Striatal Neurons

The striatum is structurally highly diverse, and its organ functionality critically depends on normal embryonic development. Although several studies have been conducted on the gene functional changes that occur during striatal development, a system-wide analysis of the underlying molecular changes is lacking. Here, we present a comprehensive transcriptome profile that allowed us to explore the trajectory of striatal development and identify the correlation between the striatal development and Huntingtons disease (HD). Furthermore, we applied an integrative transcriptomic profiling approach based on machine learning to systematically map a global landscape of 277 transcription factor (TF) networks. Most of these TF networks are linked to biological processes, and some unannotated genes provide information about the corresponding mechanisms. For example, we found that the Meis2 and Six3 were crucial for the survival of striatal neurons, which was verified using conditional knockout (CKO) mice. Finally, we used RNA-Seq to speculate their downstream targets.

neuroscience↗

Comparative transcriptomics reveal that adaptive evolution in immune genes drives the local adaptation and speciation of schizothoracine fish

Transcriptomic information can increase our understanding of the molecular processes underlying speciation. The schizothoracine fish, the largest and most diverse taxon within the Qinghai-Tibetan Plateau (QTP) ichthyofauna, are widespread in drainages throughout the QTP. These fish thus serve as an ideal model group with which to investigate how molecular evolution drives local adaptation during speciation. Here, we performed an interspecific comparative analysis of the transcriptomes of 13 schizothoracine fish species, and identified the key positively selected genes (PSGs) associated with significantly enriched functions and metabolite pathway acting on the specific lineages (or species) in the schizothoracine fish. We generated 64,637,602-83,968,472 sequence reads per schizothoracine fish species using Illumina sequencing, yielding 95,251-145,805 unigenes per species. We identified 52 out of 2,064 orthologous genes as candidate genes, which have probably been subject to positive selection along the whole schizothoracine fish lineage. Nine of these candidate genes were significantly enriched in key GO functions and metabolite pathways, all of which were associated with the immune system. The lineage-specific evolution test showed species-specific differences among the nine candidate PSGs, probably due to ecological differences among drainages, as well as among micro-habitats in the same drainage (e.g., benthic and pelagic). Here, we provide evidence that the adaptive evolution of immune genes, along with the uplift of the QTP, allowed new schizothoracine species to colonize ecologically novel environments or to exploit vacant ecological niches during speciation.\n\nSupplemental material available at FigShare: https://doi.org/10.25387/.

evolutionary biology↗

A molecular phylogeny of Schizothoracinae (Teleostei: Cypriniformes: Cyprinidae) based on 12 protein-coding mitochondrial genes and RAG1 gene analysis

The ever-increasing interest in the investigation of origin and speciation of schizothoracine fishes can be dated to 20th century. However, molecular phylogeny of Schizothoracinae and their phylogenetic relationships, as well as the divergence times still remain controversial. In this study, two DNA sets consisting of 12 protein-coding mitochondrial genes from 254 individuals and RAG1 gene from 106 individuals were used to reconstruct the phylogenetic relationships and calculate the divergence times among the subfamily schizothoracinae. Our results indicated that both of the data sets supported a non-monophyletic relationship due to involving of species of Barbinae. However, the phylogenetic relationships based on mtDNA genes were more reliable than that inferred from RAG1 gene. The highly specialized grade formed a monophyletic group, together with Ptychobarbus as a sister group of Diptychus and Gymnodiptychus, which was belonging to specialized grade, indicating that Ptychobarbus may be transition species to involve to highly specialized schizothoracianae. In addition, the primitive grade clustered with Percocypris pingi, a species of Barbinae. Based on mtDNA gene, the speciation time of Schizothoracinae was 66 Ma, and the divergence time of the primitive grade and Percocypris pingi was 64 Ma. The speciation times of the three grades Schizothoracinae were 57 Ma, 51 Ma and 43 Ma, respectively; and the divergence time of specialized and highly specialized grade was 46 Ma. The divergence times of three grades were not consistent with the three stages of uplift of Qinghai-Tibet Plateau, which is older than the times.

molecular biology↗