Biology subjects

Shao, C.

Publications and source records attributed to Shao, C..

54 records · Page 3Linked to original sources

bioRxiv2022

Splicing factor BUD31 promotes ovarian cancer progression through sustaining the expression of anti-apoptotic BCL2L12

Dysregulated expression of splicing factors has important roles in cancer development and progression. However, it remains a challenge to identify the cancer-specific splicing variants. Here we demonstrated that spliceosome component BUD31 is increased in ovarian cancer, and its higher expression predicts worse prognosis. We characterized the BUD31 binding motif and found that BUD31 preferentially binds exon-intron regions near splicing sites by CLIP-seq. Further analysis revealed that BUD31 inhibition results in extensive exon skipping and decreased abundance of long CDS isoforms. In particular, we identified BCL2L12, an anti-apoptotic BCL2 family member, as a functional splicing target of BUD31. BUD31 stimulates the inclusion of exon 3 to generate full-length BCL2L12 and promotes ovarian cancer progression. Knockdown of BUD31 or splice-switching antisense oligonucleotide treatment promotes exon 3 skipping and results in a truncated isoform of BCL2L12 that undergoes nonsense-mediated mRNA decay, and the cells subsequently undergo apoptosis. Our findings reveal BUD31-regulated exon inclusion as a critical factor in ovarian cancer cell survival and progression.

cancer biology↗

bioRxiv2021

Gdnf, a germ cell-derived factor, regulates zebrafish germ cell stemness through the creation of new spermatogonial niches (germ and Sertoli cells) and inhibition of spermatogonial differentiation in an autocrine and paracrine manners

Glial cell line-derived neurotrophic factor (GDNF) and its receptor (GDNF Family Receptor 1 - GFR1) are well known to mediate spermatogonial stem cell (SSC) proliferation and survival in the mammalian testes. In nonmammalian species, Gdnf and Gfr1 orthologs have been found but their functions remain poorly investigated in the testis. Considering this background, this study aimed to understand the roles of Gdnf-Gfr1 signaling pathway in the zebrafish testis by combining in vivo, in silico and ex vivo approaches. Our analysis showed that zebrafish exhibited two paralogs of Gndf (gdnfa and gdnfb) and its receptor, Gfr1 (gfr1a and gfr1b), in agreement with the teleost-specific third round (3R) of whole genome duplication. Expression analysis further revealed that gdnfa and gfr1a were the most expressed copies in the zebrafish adult testes. Subsequently, we demonstrated that gdnfa is expressed in the germ cells, while Gfr1a was detected in early spermatogonia (mainly in types Aund and Adiff) and Sertoli cells. Functional ex vivo analysis showed that Gdnf promoted the creation of new available niches by stimulating proliferation of both type Aund spermatogonia and their surrounding Sertoli cells, but without changing pou5f3 mRNA levels. Strikingly, Gdnf also inhibited late spermatogonial differentiation as shown by the decrease of type B spermatogonia and down-regulation of dazl in the co-treatment with Fsh. Altogether, our data revealed for the first time that a germ cell-derived factor is associated with maintaining germ cell stemness through the creation of new available niches, supporting development of differentiating spermatogonial cysts and inhibiting late spermatogonial differentiation in autocrine and paracrine manners.

cell biology↗

bioRxiv2021

mslp: a comprehensive pipeline in predicting cancer mutations specific synthetic lethal partners

BackgroundMutation specific synthetic lethal partners (SLPs) offer significant insights in identifying novel targets and designing personalized treatments in cancer studies. Large scale genetic screens in cell lines and model organisms provide crucial resources for mining SLPs, yet those experiments are expensive and might be difficult to set up. Various computational methods have been proposed to predict the potential SLPs from different perspectives. However, those efforts are hampered by the low signal-to-noise ratio in simple correlation based approaches, or incomplete reliable training sets in supervised approaches. ResultsHere we present mslp, a comprehensive pipeline to identify potential SLPs via integrating genomic and transcriptomic datasets from both patient tumours and cancer cell lines. Leveraging cuttingedges algorithms, we identify a broad spectrum of primary SLPs for mutations presented in patient tumours. Further, for mutations detected in cell lines, we develop the idea of consensus SLPs which are also identified as screen hits, and show consistency impact on cell viability. Applied in real datasets, we successfully identified known synthetic lethal gene pairs. Remarkably, genetic screen results suggested that consensus SLPs have a significant impact on cell viability compared to common hits. ConclusionsMslp is a powerful and flexible pipeline to identify potential SLPs in a cancer context-specific manner, which might aid in drug developments and precise medicines in cancer treatments. The pipeline is implemented in R and freely available in github.

bioinformatics↗

bioRxiv2021

ZetaSuite, A Computational Method for Analyzing Multi-dimensional High-throughput Data, Reveals Genes with Opposite Roles in Cancer Dependency

The rapid advance of high-throughput technologies has enabled the generation of two-dimensional or even multi-dimensional high-throughput data, e.g., genome-wide siRNA screen (1st dimension) for multiple changes in gene expression (2nd dimension) in many different cell types or tissues or under different experimental conditions (3rd dimension). We show that the simple Z-based statistic and derivatives are no longer suitable for analyzing such data because of the accumulation of experimental noise and/or off-target effects. Here, we introduce ZetaSuite, a statistical package designed to score and rank hits from two-dimensional screens, construct regulatory networks based on response similarities, and eliminate off-targets. Applying this method to two large cancer dependency screen datasets, we identify not only genes critical for cell fitness, but also those required for constraining cell proliferation. Strikingly, most of those cancer constraining genes function in DNA replication/repair checkpoint, suggesting that cancer cells also need to protect their genomes for long-term survival.

cell biology↗

bioRxiv2021

MYCN mediates cysteine addiction and sensitizes to ferroptosis

Aberrant expression of MYC family members predicts poor clinical outcome in many human cancers. Oncogenic MYC profoundly alters metabolism and mediates an antioxidant response to maintain redox balance. Here we show that MYC induces massive lipid peroxidation upon depletion of cysteine, the rate-limiting amino acid for glutathione biosynthesis and sensitizes cells to ferroptosis, an oxidative, non-apoptotic and irondependent type of cell death. In MYCN-amplified childhood neuroblastoma, MYCN mediates resistance to ferroptosis by activating transsulfuration of methionine to cysteine. MYCN may contribute to spontaneous tumor regression in low-risk neuroblastomas by promoting ferroptosis in cells with epigenetically silenced cystathionine-beta-synthase, the rate-limiting enzyme for transsulfuration. We identified enzymes and antiporter proteins crucial to ferroptotic escape, providing multiple previously unknown sites that may be acted on therapeutically.

cancer biology↗

bioRxiv2021

Deep neural network analysis employing diffusion basis spectrum imaging metrics as classifiers improves prostate cancer detection and grading

Structural and cellular complexity of prostatic histopathology limits the accuracy of noninvasive detection and grading of prostate cancer (PCa). We addressed this limitation by employing a novel diffusion basis spectrum imaging (DBSI) to derive structurally-specific diffusion fingerprints reflecting various underlying prostatic structural and cellular components. We further developed diffusion histology imaging (DHI) by combining DBSI-derived structural fingerprints with a deep neural network (DNN) algorithm to more accurately classify different histopathological features and predict tumor grade in PCa. We examined 243 patients suspected with PCa using in vivo DBSI. The in vivo DBSI-derived diffusion metrics detected coexisting prostatic pathologies distinguishing inflammation, PCa, and benign prostatic hyperplasia. DHI distinguished PCa from benign peripheral and transition zone tissues with over 95% sensitivity and specificity. DHI also demonstrated over 90% sensitivity and specificity for Gleason score noninvasively. We present DHI as a novel diagnostic tool capable of noninvasive detection and grading of PCa. One sentence summaryDiffusion histology imaging noninvasively and accurately detects and grades prostate cancer.

bioinformatics↗

bioRxiv2021

Contemporary clinical isolates of Staphylococcus aureus from pediatric osteomyelitis patients display unique characteristics in a mouse model of hematogenous osteomyelitis

Osteomyelitis can result from the direct inoculation of pathogens into bone during injury or surgery, or from spread via the bloodstream, a condition called hematogenous osteomyelitis (HOM). HOM disproportionally affects children, and more than half of cases are caused by Staphylococcus (S.) aureus. Laboratory models of osteomyelitis mostly utilize direct injection of bacteria into the bone or the implantation of foreign material, and therefore do not directly interrogate the pathogenesis of pediatric hematogenous osteomyelitis. In this study, we inoculated mice intravenously and characterized resultant musculoskeletal infections using two strains isolated from adults (USA300-LAC and NRS384) and five new methicillin-resistant S. aureus isolates from pediatric osteomyelitis patients. All strains were capable of creating stable infections over five weeks, although the incidence varied. Micro-computed tomography (microCT) analysis demonstrated decreases in trabecular bone volume fraction but little effect on bone cortices. Histologic assessment revealed differences in the precise focus of musculoskeletal infection, with varying mixtures of bone-centered osteomyelitis and joint-centered septic arthritis. Whole genome sequencing of three new isolates demonstrated distinct strains, two within the USA300 lineage and one USA100 isolate. Interestingly, the USA100 strain showed a distinct predilection for septic arthritis, compared to the USA300 strains, including NRS384 and LAC, which more frequently led to osteomyelitis or mixed bone and joint infections. Collectively, these data outline the feasibility of using pediatric osteomyelitis clinical isolates to study the pathogenesis of HOM in murine models and lay the groundwork for future studies investigating strain-dependent differences in musculoskeletal infection. ImportanceThe inflammation of bone tissue is called osteomyelitis, and more than half of cases are caused by an infection with the bacterium Staphylococcus aureus. In children, the most common route of infection is hematogenous, wherein bacteria seed the bone from the bloodstream without another known site of infection. Although these infections pose a significant health problem, they are understudied in the laboratory because of a dearth of robust animal models. In this study, we utilized several previously uncharacterized clinical isolates of S. aureus derived from children with bone infections to generate reproducible and stable musculoskeletal infection in mice with many features seen in human osteomyelitis, making them a valuable resource for future mechanistic and therapeutic studies.

pathology↗

bioRxiv2021

A global multiregional proteomic map of the human cerebral cortex

The Brodmann area (BA)-based map is one of the most widely used cortical maps for studies of human brain functions and in clinical practice; however, the molecular architecture of BAs remain unknown. The present study provided a global multiregional proteomic map of the human cerebral cortex by analyzing 29 BAs. These 29 BAs were grouped into 6 clusters based on similarities in proteomic patterns: the motor and sensory cluster, vision cluster, auditory cluster and Brocas area, Wernickes area cluster, cingulate cortex cluster, and heterogeneous function cluster. We identified 474 cluster-specific and 134 BA-specific signature proteins whose functions are closely associated with specialized functions and disease vulnerability of the corresponding cluster or BA. The findings of the present study could provide explanations for the functional connections between the anterior cingulate cortex and sensorimotor cortex and for anxiety-related function in the sensorimotor cortex. The brain transcriptomic and proteomic comparison indicated that they both could reflect the function of cerebral cortex, but showed different characteristics. These proteomic data are publicly available at the Human Brain Proteome Atlas (www.brain-omics.com). Our results may enhance our understanding of the molecular basis of brain functions and provide an important resource to support human brain research.

neuroscience↗

bioRxiv2020

Chemoproteomics Maps Glycolytic Targetome in Cancer Cells

Hyperactivated glycolysis, favoring uncontrolled growth and metastasis by producing essential metabolic intermediates engaging bioenergetics and biosynthesis, is a metabolic hallmark of most cancer cells. Although sporadic information has revealed glycolytic metabolites also possess non-metabolic function as signaling molecules, it remains largely elusive how these metabolites interact with and functionally regulate their binding targets. Here we introduce a Target Responsive Accessibility Profiling (TRAP) approach that measures ligand binding-induced steric hindrance in protein targets via global profiling accessibility changes in reactive lysines, and mapped 913 target candidates and 2,487 interactions for 10 major glycolytic metabolites in cancer cells via TRAP. The elucidated targetome uncovers diverse regulatory modalities of glycolytic metabolites involving the direct perturbation of carbohydrate metabolism enzymes, intervention of transcriptional control, modulation of proteome-level acetylation and protein complex assemblies. The advantages gained from glycolysis by cancer cells are expanded by discovering lactate as a ligand for an orphan transcriptional regulator TRIM 28 that promotes p53 degradation, and by identifying pyruvate acting against a cell apoptosis inducer trichostatin A via attenuating protein acetylation. Lastly, the inhibition of glycolytic key enzymes led to identify an intrinsically active glycolytic intermediate glyceraldehyde 3-phosphate that elicits its cytotoxicity by engaging with ENO1 and MTHFD1. Collectively, the glycolytic targetome depicted by TRAP constitutes a fertile resource for understanding how glycolysis finely tunes metabolism and signaling in support of cancer cells, and fostering the exploitation of glycolytic targetome as promising nodes for anti-cancer therapeutics development.

cancer biology↗

bioRxiv2020

Individual cell-based modeling of tumor cell plasticity-induced immune escape after CAR-T therapy

Chimeric antigen receptor (CAR) therapy targeting CD19 is an effective treatment for refractory B cell malignancies, especially B cell acute lymphoblastic leukemia (B-ALL). The majority of patients achieve a complete response following a single infusion of CD19-targeted CAR-modified T cells (CAR-19 T cells); however, many patients suffer relapse after therapy, and the underlying mechanism remains unclear. To better understand the mechanism of tumor relapse, we developed an individual cell based computational model for tumor cell plasticity and the heterogeneous responses to the CAR-T treatment. Model simulations reproduced the process of tumor relapse, and predicted that CAR-T stress-induced cell plasticity can lead to tumor relapse in B-ALL. Model predictions were verified by applying the second-generation CAR-T cells to mice injected with NALM-6-GL leukemic cells, in which 60% of the mice relapse within 3 months, and relapsed tumors retained CD19 expression but exhibited a subpopulation of cells with CD34 transcription. These findings lead to a mechanism of tumor replace by which CAR-T treatment induced tumor cells to transition to hematopoietic stem-like cells (HSLCs) and myeloid-like cells and hence escape of CAR-T targeting. The computational model framework was successfully developed to recapitulate the individual evolutionary dynamics, which could predict clinical survival outcomes in B-ALL patients after CAR-T therapy.

cancer biology↗

bioRxiv2019

Rapidly cycling stem cells regenerate the intestine independent of Lgr5high cells

The +4 cells in intestinal crypts are DNA damage-resistant and contribute to regeneration. However, their exact identity and the mechanism underlying +4 cell-mediated regeneration remain unclear. Using lineage tracing, we show that cells marked by an Msi1 reporter (Msi1+) are enriched at the +4 position in intestinal crypts and exhibit DNA damage resistance. Single-cell RNA sequencing reveals that the Msi1+ cells are heterogeneous with the majority being intestinal stem cells (ISCs). The DNA damage-resistant subpopulation of Msi1+ cells is characterized by low-to-negative Lgr5 expression and is more rapidly cycling than Lgr5high radio-sensitive crypt base columnar stem cells (CBCs); they enable fast repopulation of the intestinal epithelium independent of CBCs that are largely depleted after irradiation. Furthermore, relative to CBCs, Msi1+ cells preferentially produce Paneth cells during homeostasis and upon radiation repair. Together, we demonstrate that the DNA damage-resistant Msi1+ cells are rapidly cycling ISCs that maintain and regenerate the intestinal epithelium.

cell biology↗

bioRxiv2019

Chromosome-level genome assembly of the greenfin horse-faced filefish (Thamnaconus septentrionalis) using Oxford Nanopore PromethION sequencing and Hi-C technology

The greenfin horse-faced filefish, Thamnaconus septentrionalis, is a valuable commercial fish species that is widely distributed in the Indo-West Pacific Ocean. It has characteristic blue-green fins, rough skin and spine-like first dorsal fin. T. septentrionalis is of a conservation concern as a result of sharply population decline, and it is an important marine aquaculture fish species in China. The genomic resources of this filefish are lacking and no reference genome has been released. In this study, the first chromosome-level genome of T. septentrionalis was constructed using Nanopore sequencing and Hi-C technology. A total of 50.95 Gb polished Nanopore sequence were generated and were assembled to 474.31 Mb genome, accounting for 96.45% of the estimated genome size of this filefish. The assembled genome contained only 242 contigs, and the achieved contig N50 was 22.46 Mb, reaching a surprising high level among all the sequenced fish species. Hi-C scaffolding of the genome resulted in 20 pseudo-chromosomes containing 99.44% of the total assembled sequences. The genome contained 67.35 Mb repeat sequences, accounting for 14.2% of the assembly. A total of 22,067 protein-coding genes were predicted, of which 94.82% were successfully annotated with putative functions. Furthermore, a phylogenetic tree was constructed using 1,872 single-copy gene families and 67 unique gene families were identified in the filefish genome. This high quality assembled genome will be a valuable genomic resource for understanding the biological characteristics and for facilitating breeding of T. septentrionalis.

genomics↗

bioRxiv2019

Trading Genome Vulnerability for Stable Genetic Inheritance: Active Retrotransposons Help Maintain Pericentromeric Heterochromatin Required for Faithful Cell Division

Retrotransposons are extensively populated in vertebrate genomes, which, when active, are thought to cause genome instability with potential benefit to genome evolution. Retrotransposon-derived RNAs are also known to give rise to small endo-siRNAs to help maintain heterochromatin at their sites of transcription; however, as not all heterochromatic regions are equally active in transcription, it remains unclear how heterochromatin is maintained across the genome. Here, we attack these problems by defining the origins of repeat-derived RNAs and their specific chromatin registers in Drosophila S2 cells. We demonstrate that repeat RNAs are predominantly derived from active Gypsy elements, and upon their processing by Dicer-2, these endo-siRNAs act in cis and trans to help maintain pericentromeric heterochromatin. Remarkably, we show that synthetic repeat-derived siRNAs are sufficient to rescue Dicer-2 deficiency-induced defects in heterochromatin formation in interphase and chromosome segregation during mitosis, thus demonstrating that active retrotransposons are actually required for stable genetic inheritance.

genomics↗

bioRxiv2019

Exponential Growth of Glioblastoma In Vivo Driven by Rapidly Dividing and Outwardly Migrating Cancer Stem Cells

How overall tumor growth emerges from the properties of functionally heterogeneous tumor cell subpopulations is a fundamental question of cancer biology. Here we combined lineage tracing, continuous monitoring of tumor mass, proliferation assays and transcriptomics with mathematical modeling and statistical inference to dissect the growth of glioblastoma in mice. We found that tumors grow exponentially at the rate of symmetric divisions of brain tumor stem cells (BTSCs). Spatial modeling predicts, and data show, that BTSCs accumulate at the tumor rim rather than in the core. The physiological differentiation hierarchy downstream of BTSCs is preserved in mice and humans: transit amplifying progenitors give rise to terminally differentiated cells. Consistent with our quantification of the mechanisms underlying tumor growth, molecular data show elevated expression of cell cycle-and migration-related genes in BTSCs. Our systematic approach reveals fundamental properties of glioblastoma and may be transferable to the study of other animal models of cancer.

cancer biology↗

bioRxiv2019

Bactericidal efficiency and mechanism of specifically targeted antimicrobial peptides optimized based on structural and functional relationships

In contrast to traditional broad-spectrum antibiotics, it is difficult for bacteria to develop resistance to most specifically targeted antimicrobial peptides (STAMPs), moreover, they can maintain a normal ecological balance and provide long-term protection for the body. However, therapeutic applications of STAMPS are hindered by their weak activity, and imperfect specificity as well as lack of knowledge to understand their structure-activity relationships. To further investigate the effects of different parameters on the biological activities of STAMPs, a peptide sequence, WKKIWKDPGIKKWIK, was truncated, extended, and provided with an increased charge and altered amphipathicity. In addition, a novel template modification method was introduced, in which a phage-displayed peptide that recognized and bound to E. coli cells was attached at the end of the sequence. Compared with the traditional template modification method, peptide 11, which contained a phage-displayed peptide at the C-terminus, exhibited superior narrow-spectrum antibacterial activity against E. coli compared to that of parental peptide 2, and the activity and specificity of 11 were increased by 5.0 and 2.4 times, respectively. Additionally, 11 showed low cell toxicity and relatively desirable salt, serum, acid and alkaline stability. In this study, 11 specifically killed E. coli by causing cytoplasmic membrane rupture and cytosol leakage. In summary, these findings are useful for improving the activity and specificity of STAMPs and show that peptide 11 is better able to combat the growing threat of E. coli infections.

biochemistry↗

bioRxiv2019

Dynamic chromosome rearrangements of the white-spotted bamboo shark shed light on cartilaginous fish diversification mechanisms

Cartilaginous fishes have a very high phenotypical diversity, a phenomenon for which the mechanisms have been largely unexplored. Here, we report the genome of the white-spotted bamboo shark as the first chromosome-level genome assembly of cartilaginous fish. Using this genome, we illustrated a dynamic chromosome rearrangement process in the bamboo shark, which resulted in the formation of 13 chromosomes, all of which were sparsely distributed with conserved genes and fast-evolving. We found the fast-evolving chromosomes to be enriched in immune-related genes with two chromosomes harboring the major genes for developing the single-chain antibody. We also found chromosome rearrangements to have resulted in the loss of two genes (p2rx3 and p2rx5) which we also showed were involved in cartilage development using a CRISPR/Cas9 approach in zebrafish. Our study highlighted the significance of chromosome rearrangements in the phenotypical evolution of cartilaginous fishes, providing clues to inform further studies on mechanisms for fish diversification.

genomics↗

bioRxiv2018

Immunogenicity and protective potency of Norovirus GII.17 virus-like particle-based vaccine

Noroviruses (NoVs) are a major cause of acute viral gastroenteritis in adults and children worldwide. Lacking of cell culture system and animals models that must be considered the virus like particles (VLPs) used as an effective vaccine development. In the present study, we investigated the expression of the major capsid protein (VP1) of Genogroup II, genotype 17 (GII.17) NoV using recombinant baculovirus system in insect cells and saliva binding blockade assay to detect their protective potency. Our results showed that GII.17 VLPs could be successfully generated in sf9 insect cells and electron microscopic revealed that GII.17 VLPs was visualized as spherical particles of -35nm in diameter. Immunized mouse with purified VLPs produced GII.17 specific sera and could efficiently block GII.17 VLPs binding to saliva histo-blood group antigens (HBGAs). Together, these results suggested that GII.17 VLPs represent a promising vaccine candidate against NoV GII.17 infection and strongly support further preclinical and clinical studies.

immunology↗

bioRxiv2018

Continuous Evaluation of Ligand Protein Predictions: A Weekly Community Challenge for Drug Docking

1Docking calculations can be used to accelerate drug discovery by providing predictions of the poses of candidate ligands bound to a targeted protein. However, studies in the literature use varied docking methods, and it is not clear which work best, either in general or for specific protein targets. In addition, a complete docking calculation requires components beyond the docking algorithm itself, such as preparation of the protein and ligand for calculations, and it is difficult to isolate which aspects of a method are most in need of improvement. To address such issues, we have developed the Continuous Evaluation of Ligand Protein Predictions (CELPP), a weekly blinded challenge for automated docking workflows. Participants in CELPP create a workflow to predict protein-ligand binding poses, which is then tasked with predicting 10-100 new (never before released) protein-ligand crystal structures each week. CELPP evaluates the accuracy of each workflows predictions and posts the scores online. CELPP is a new cyberinfrastructure resource to identify the strengths and weaknesses of current approaches, help map docking problems to the algorithms most likely to overcome them, and illuminate areas of unmet need in structure-guided drug design.

biophysics↗