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Biology subjects

Sheng, R.

Publications and source records attributed to Sheng, R..

12 recordsLinked to original sources

Functional characterization of bat limb regulatory elements

Bats are the only mammals capable of powered flight and roost head-down. However, the molecular changes shaping bat limbs remain largely unknown. Here, we used comparative functional genomics coupled with mouse-bat sequence swaps to identify key regulatory elements important in bat limb development. We generated and compared bat and mouse forelimb and hindlimb genomic datasets at key wing developmental timepoints, followed by mouse enhancer assays to characterize sequences showing differences between species. We then swapped six mouse enhancer sequences with their corresponding bat sequences, obtaining a variety of bat limb associated phenotypes, including ossification delay, longer digits, thicker skin and symmetrical hindlimb digits. Our work provides a genomic catalog of genes and regulatory elements involved in bat limb development and through extensive characterization in mice shows how changes in regulatory elements lead to small phenotypic changes that together contribute to bat limb development.

developmental biology↗

Biodegradable Intra-arterial Devices for Focal Drug Delivery to Targeted Organs

This study presents the development of biodegradable intra-arterial drug delivery (IADD) devices for the focal treatment of targeted organs. The IADD devices are fabricated using magnesium (Mg) and poly(glycerol sebacate) (PGS), leveraging their biocompatibility and tunable biodegradability, and are loaded with two model drugs, dexamethasone (DEX) or cisplatin (CIS). The IADD devices with helical and linear designs were fabricated for focal drug delivery to targeted organs and characterized for their microstructure and composition using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The results confirmed the successful incorporation and stability of the drugs within the device. The IADD devices demonstrated in vitro release of DEX and CIS over 30 days, with drug-dependent and fabrication-dependent release profiles. The IADD devices demonstrated cytocompatibility with endothelial cells and sustained pharmacological activity against glioma cells throughout the in vitro release period. DEX-loaded IADD devices were implanted into the artery upstream of a target organ in rat models. The devices implanted into the renal artery to target the kidney and the carotid artery to target the brain achieved 109-fold and 68-fold improvements, respectively, in organ vs systemic drug levels compared to oral drug administration. Arterial histology and explanted-device analysis provided preliminary evidence of local vascular tolerability and device integrity over the examined implantation period. Overall, these results support IADD devices as a proof-of-concept approach for focal intra-arterial drug delivery to targeted organs, demonstrating substantially elevated target-organ drug levels relative to systemic exposure. HighlightsO_LIIntroduction of a novel intra-arterial drug delivery (IADD) platform C_LIO_LIIADD devices were fabricated from bioresorbable Mg and drug-loaded PGS C_LIO_LIDEX- and CIS-loaded IADD devices were evaluated for in vitro release and bioactivity C_LIO_LIIADD delivery achieved marked DEX enrichment in the kidney and brain C_LIO_LIPost-implantation studies support preliminary vascular safety C_LI

bioengineering↗

Wnt specifically induces FZD5/8 endocytosis and degradation and the involvement of RSPO-ZNRF3/RNF43 and DVL

Frizzled (FZD) proteins are the principal receptors of the Wnt signaling pathway. However, whether Wnt ligands induce FZD endocytosis and degradation remains elusive. The transmembrane E3 ubiquitin ligases ZNRF3 and RNF43 were reported to promote the endocytosis and degradation of FZD receptors to inhibit Wnt signaling, and their function is antagonized by R-spondin (RSPO) proteins. However, the dependency of RSPO-ZNRF3/RNF43-mediated FZD endocytosis and degradation on Wnt stimulation, as well as the specificity of this degradation for different FZD, remains unclear. Here, we demonstrated that Wnt induces FZD5/8 endocytosis and degradation in a ZNRF3/RNF43-dependent manner. ZNRF3/RNF43 selectively targets FZD5/8 for degradation upon Wnt stimulation. RSPO1 enhances Wnt signaling by specifically stabilizing FZD5/8. Wnt promotes the interaction between FZD5 and RNF43. We further demonstrated that DVL proteins promote ligand-independent endocytosis of FZD but are dispensable for Wnt-induced FZD5/8 endocytosis and degradation. Our results reveal a novel negative regulatory mechanism of Wnt signaling at the receptor level and illuminate the mechanism by which RSPO-ZNRF3/RNF43 regulates Wnt signaling, which may provide new insights into regenerative medicine and cancer therapy.

cell biology↗

CRISPR screens reveal convergent targeting strategies against evolutionarily distinct chemoresistance in cancer

Resistance to chemotherapy has been a major hurdle that limits therapeutic benefits for many types of cancer. Here we systematically identify genetic drivers underlying chemoresistance by performing 30 genome-scale CRISPR knockout screens for seven chemotherapeutic agents in multiple cancer cells. Chemoresistance genes vary between conditions primarily due to distinct genetic background and mechanism of action of drugs, manifesting heterogeneous and multiplexed routes towards chemoresistance. By focusing on oxaliplatin and irinotecan resistance in colorectal cancer, we unravel that evolutionarily distinct chemoresistance can share consensus vulnerabilities identified by 26 second-round CRISPR screens with druggable gene library. We further pinpoint PLK4 as a therapeutic target to overcome oxaliplatin resistance in various models via genetic ablation or pharmacological inhibition, highlighting a single-agent strategy to antagonize evolutionarily distinct chemoresistance. Our study not only provides resources and insights into the molecular basis of chemoresistance, but also proposes potential biomarkers and therapeutic strategies against such resistance.

cancer biology↗

Golgi-associated retrograde protein (GARP) complex recruits retromer to trans-Golgi network for FgKex2 and FgSnc1 recycling, necessary for development and pathogenicity of Fusarium graminearum

In eukaryotic cells, the retromer complex plays a crucial role in orchestrating the sorting and retrograde transport of cargo proteins from endosomes to the trans-Golgi network (TGN). Despite its significance, the molecular details of this intracellular trafficking process remain unclear. Here, we identified a Golgi-associated retrograde protein (GARP) complex as a mediator of vesicular transport, facilitating the recruitment of the retromer complex to TGN to exert its functions. The GARP complex is mainly localized to the TGN, where it interacts with the retromer complex. This interaction is evolutionarily conserved across different species. Furthermore, we identified FgKex2 and Fgsnc1 as cargo proteins in the GARP/retromer-mediated recycling pathway. Loss of GARP or retromer results in a complete mis-sorting of FgKex2 and FgSnc1 to the vacuolar degradation pathway, which affects the growth, development, toxisome biogenesis, and pathogenicity of F. graminearum. In summary, we assert that GARP facilitates the recruitment of retromer from endosomes to the TGN, orchestrating the recycling of FgKex2 and FgSnc1. This is integral to sustaining continuous growth, development and contributes significantly to the pathogenicity of F. graminearum.

microbiology↗

Association of an estrogen-sensitive Pax1-Col11a1-Mmp3 signaling axis with adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than five-fold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here we sought to define the roles of PAX1 and newly-identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); P=7.07e-11, OR=1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1-/-). In postnatal spines we found that PAX1 and collagen (1) XI protein both localize within the intervertebral disc (IVD)-vertebral junction region encompassing the growth plate, with less collagen (1) XI detected in Pax1-/- spines compared to wildtype. By genetic targeting we found that wildtype Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, this suppression was abrogated in the presence of the AIS-associated COL11A1P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2, or tamoxifen treatment, significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a Pax1-Col11a1-Mmp3 signaling axis in spinal chondrocytes.

genetics↗

Implantation of engineered adipocytes that outcompete tumors for resources suppresses cancer progression

Tumors acquire an increased ability to obtain and metabolize nutrients. Here, we engineered and implanted adipocytes to outcompete tumors for nutrients and show that they can substantially reduce cancer progression. Growing cells or xenografts from several cancers (breast, colon, pancreas, prostate) alongside engineered human adipocytes or adipose organoids significantly suppresses cancer progression and reduces hypoxia and angiogenesis. Transplanting modulated adipocyte organoids in pancreatic or breast cancer mouse models nearby or distal from the tumor significantly suppresses its growth. To further showcase therapeutic potential, we demonstrate that co-culturing tumor organoids derived from human breast cancers with engineered patient-derived adipocytes significantly reduces cancer growth. Combined, our results introduce a novel cancer therapeutic approach, termed adipose modulation transplantation (AMT), that can be utilized for a broad range of cancers.

cancer biology↗

Integrative single-cell characterization of hypothalamus sex-differential and obesity-associated genes and regulatory elements

Over 500 noncoding genomic loci are associated with obesity. The majority of these loci reside near genes that are expressed in the hypothalamus in specific neuronal subpopulations that regulate food intake, hindering the ability to identify and functionally characterize them. Here, we carried out integrative single-cell analysis (RNA/ATAC-seq) on both mouse and human male and female hypothalamus to characterize genes and regulatory elements in specific cell subpopulations. Utilizing both transcriptome and regulome data, we identify over 30 different neuronal and non-neuronal cell subpopulations and a shared core of transcription factors that regulate cell cluster-specific genes between mice and humans. We characterize several sex-specific differentially expressed genes and the regulatory elements that control them in specific cell subpopulations. Overlapping cell-specific scATAC peaks with obesity-associated GWAS variants, identifies potential obesity-associated regulatory elements. Using reporter assays and CRISPR editing, we show that many of these sequences, including the top obesity-associated loci (FTO and MC4R), are functional enhancers whose activity is altered due to the obesity-associated variant and regulate known obesity genes. Combined, our work provides a catalog of genes and regulatory elements in hypothalamus cell subpopulations and uses obesity to showcase how integrative single-cell sequencing can identify functional variants associated with hypothalamus-related phenotypes.

neuroscience↗

USP10 strikes down Wnt/β-catenin signaling by dual-wielding deubiquitinase activity and phase transition potential

Wnt/{beta}-catenin signaling is a conserved pathway crucially governing development, homeostasis and oncogenesis. Discovery of novel regulators holds great values in both basic and translational research. Through screening, we identified a deubiquitinase (DUB) USP10 as a novel and critical modulator of {beta}-catenin. Mechanistically, USP10 binds to key scaffold Axin1 via conserved motifs and stabilizes Axin1 through K48-linked deubiquitination, and surprisingly, tethers Axin1 and {beta}-catenin physically while promoting phase separation for {beta}-catenin suppression regardless of its enzymatic activity. Functionally, USP10 prominently regulates embryonic development and intestinal homeostasis by antagonizing {beta}-catenin via DUB activity. In colorectal cancer, USP10 substantially represses cancer growth mainly through physical binding compensation and phase separation promotion and correlates with Wnt/{beta}-catenin magnitude clinically. Collectively, we discovered USP10 functioning in multiple biological processes against {beta}-catenin and unearthed a novel enzyme-dependent and -independent "dual-regulating" mechanism by which USP10 utilizes parallelly and context-dependently. USP10 inhibitor was suggested in treating certain Wnt-related diseases.

cell biology↗

Multiomics reveal that silk fibroin and sericin differentially potentiate the paracrine functions of mesenchymal stem cells and enhance tissue regeneration

Silk fibroin (SF) and sericin (SS), the two major proteins of silk, are attractive biomaterials that show great potential in regenerative medicine. However, their biochemical interactions with stem cells were not fully understood. Here, we employed multiomics to obtain a global view of the triggered cellular processes and pathways of MSCs by SF and SS. Integrated RNA-seq and proteomics revealed that SF and SS strongly enhanced the paracrine activity of MSCs through differentially activating integrin and glycolytic pathways, rather than directly regulating stem cell fate to initiate multiple but distinct biological processes in MSCs. Those specific paracrine signals of MSCs stimulated by SF and SS effectively promoted skin wound healing by influencing the behaviors of multiple resident cells in skin wound microenvironments. This study provides comprehensive and reliable insights into the cellular interactions with SF and SS, enabling future development of silk-based therapeutics for tissue engineering and stem cell therapy.

bioengineering↗

ADGRG6 promotes adipogenesis and is involved in sex-specific fat distribution

Fat distribution differences between males and females are a major risk factor for metabolic disease, but their genetic etiology remains largely unknown. Here, we establish ADGRG6 as a major factor in adipogenesis and gender fat distribution. Deletion of ADGRG6 in human adipocytes impairs adipogenesis due to reduced cAMP signaling. Conditionally knocking out Adgrg6 in mouse adipocytes or deleting an intronic enhancer associated with gender fat distribution generates males with female-like fat deposition, which are protected against high-fat-diet-induced obesity and have improved insulin response. To showcase its therapeutic potential, we demonstrate that CRISPRi targeting of the Adgrg6 promoter or enhancer prevents high-fat-diet-induced obesity. Combined, our results associate ADGRG6 as a gender fat distribution gene and highlight its potential as a therapeutic target for metabolic disease.

genomics↗

SIRT1 ameliorates premature senescence-induced defenestration in hepatic sinusoidal endothelial cell

Premature senescence, linked to progerin, involves in endothelial dysfunction and liver diseases. Activating sirtuin 1 (SIRT1) ameliorates liver fibrosis. However, the potential mechanisms of premature senescence in defenestration in hepatic sinusoidal endothelial cells (HSECs) and how SIRT1 affects fenestrae remains elusive. Our study showed that in vivo, premature senescence occurred, with decrease of SIRT1, during CCl4-induced defenestration in HSECs and liver fibrogenesis; whereas overexpressing SIRT1 with adenovirus vector lessened progerin-associated premature senescence to relieve CCl4-induced defenestration and liver fibrosis. In vitro, fenestrae in HSECs disappeared, with progerin-associated premature senescence; these effects aggravated by H2O2-induced oxidative damage. Nevertheless, knockdown of NOX2 or overexpression of SIRT1 with adenovirus vector reduced progerin-associated premature senescence to maintain fenestrae through deacetylating p53. Furthermore, more Ac p53 K381 and progerin co-localized with accumulation of actin filament (F-actin) in the nuclear envelope of H2O2-treated HSECs; in contrast, these effects were rescued by overexpressing SIRT1. In conclusion, NOX2-dependent oxidative damage aggravates defenestration in HSECs via progerin-associated premature senescence; SIRT1-mediated deacetylation of p53 maintains fenestrae and attenuates liver fibrogenesis through inhibiting premature senescence.

cell biology↗