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Biology subjects

Cui, M.

Publications and source records attributed to Cui, M..

At least 55 records · Page 3Linked to original sources

Glabridin induces paraptosis-like cell death via ER stress in breast cancer cells

Glabridin, a polyphenolic flavonoid isolated from the root of the glycyrrhiza glabra, has been demonstrated to have anti-tumor properties in human malignancies. This study found that glabridin decreased the viability of human breast cancer MDA-MB-231 and MCF7 cells in a dose-dependent manner that was not involved in the caspase-3 cascade. Glabridin promoted the formation of extensive cytoplasmic vacuolation by increasing the expression of endoplasmic reticulum (ER) stress markers BiP, XBP1s, and CHOP. The transmission electron microscopy and fluorescence with the ER chaperon KDEL suggested that the vacuoles were derived from ER. Glabridin-induced vacuolation was blocked when protein synthesis was inhibited by cycloheximide, demonstrating that protein synthesis is crucial for this process. Furthermore, we determined that glabridin causes loss of mitochondrial membrane potential as well as the production of reactive oxygen species, both of which lead to mitochondrial dysfunction. These features are consistent with a kind of programmed cell death described as paraptosis. This work reports for the first time that glabridin could induce paraptosis-like cell death, which may give new therapeutic approaches for apoptosis-resistant breast cancers.

cell biology↗

Highly efficient multiplex genome editing in dicot plants using improved CRISPR/Cas systems

CRISPR/Cas9-mediated gene editing provides a powerful tool for dissecting gene function and improving important traits in crops. However, there are still persisting challenges to obtain high homozygous/bi-allelic (ho/bi) mutations in dicot plants. Here, we develop an improved CRISPR/Cas9 system harboring a calreticulin-like gene promoter, which can boost targeted mutations in dicots. Additionally, the pDC45_dsg construct, combining a 35Spro-tRNA_sgRNA-EU unit and PCE8pro-controlled Cas9, can achieve more than 80.0% ho/bi mutations at target sites in allotetraploid tobacco. We construct pDC45_Fast system that can simultaneously fulfill gene editing and shorten the life span of T0 generation tobacco and tomato. This study provides new tools for improving targeted gene mutagenesis in dicots, and makes manipulations of genes in Solanum more feasible.

plant biology↗

Optogenetic operated probiotics to regulate host metabolism by mimicking enteroendocrine

The enteroendocrine system plays an important role in metabolism. The gut microbiome regulates enteroendocrine in an extensive way, arousing attention in biomedicine. However, conventional strategies of enteroendocrine regulation via gut microbiome are usually non-specific or imprecise. Here, an optogenetic operated probiotics system was developed combining synthetic biology and flexible electronics to achieve in situ controllable secretion to mimic enteroendocrine. Firstly, optogenetic engineered Lactococcus lactis (L. lactis) were administrated in the intestinal tract. A wearable optogenetic device was designed to control optical signals remotely. Then, L. lactis could secrete enteroendocrine hormone according to optical signals. As an example, optogenetic L. lactis could secrete glucagon-like peptide-1(GLP-1) under the control of the wearable optogenetic device. To improve the half-life of GLP-1 in vivo, the Fc domain from immunoglobulin was fused. Treated with this strategy, blood glucose, weight and other features were relatively well controlled in rats and mice models. Furthermore, up-conversion microcapsules were introduced to increase the excitation wavelength of the optogenetic system for better penetrability. This strategy has biomedical potential in metabolic diseases therapy by mimicking enteroendocrine.

bioengineering↗

Tagging active neurons by soma-targeted Cal-Light

Verifying causal effects of neural circuits is essential for proving direct a circuit-behavior relationship. However, techniques for tagging only active neurons with high spatiotemporal precision remain at the beginning stages. Here we developed the soma-targeted Cal-Light (ST-Cal-Light) which selectively converts somatic calcium rise triggered by action potentials into gene expression. Such modification simultaneously increases the signal-to-noise ratio (SNR) of reporter gene expression and reduces the light requirement for successful labeling. Because of the enhanced efficacy, the ST-Cal-Light enables the tagging of functionally engaged neurons in various forms of behaviors, including context-dependent fear conditioning, leverpressing choice behavior, and social interaction behaviors. We also targeted kainic acid-sensitive neuronal populations in the hippocampus which subsequently suppressed seizure symptoms, suggesting ST-Cal-Lights applicability in controlling disease-related neurons. Furthermore, the generation of a conditional ST-Cal-Light knock-in (KI) mouse provides an opportunity to tag active neurons in a region- or cell-type specific manner via crossing with other Cre-driver lines. Thus, the versatile ST-Cal-Light system links somatic action potentials to behaviors with high temporal precision, and ultimately allows functional circuit dissection at a single cell resolution.

neuroscience↗

Angiocrine IGFBP3 Spatially Coordinates IGF Signaling During Neonatal Cardiac Regeneration

To identify non-cell-autonomous effectors of cardiomyocyte mitosis, we analyzed a transcriptomic screen of regenerating and non-regenerating neonatal hearts for differentially-expressed secreted proteins - which we hypothesized could include candidate mitogens. We identified and validated IGFBP3, which has a Janus-like stabilizing and sequestering effect on IGF growth factors, as a neonatal injury-associated secreted protein. IGFBP3 is expressed by and secreted from vascular cells in the neonatal heart after cardiac injury, notably in the infarct border zone. We found that global deletion of IGFBP3 blunted neonatal regeneration, while gain-of-function experiments using recombinant IGFBP3 and a transgenic mouse model uncovered a pro-mitotic effect of IGFBP3 on cardiomyocytes in vitro and in the adult heart. We show that site-specific expression of an IGFBP3 protease (PAPP-A2) and its inhibitor (STC2) coordinate the spatial release of IGF2 in the infarct zone to regio-selectively activate the INSR-ERK-AKT cell growth pathways in cardiomyocytes. Collectively, our work highlights the spatiotemporal orchestration of endothelial-cardiomyocyte interactions that are required for neonatal cardiac regeneration.

cell biology↗

Crystal structure of a constitutive active mutant of adenosine A2A receptor

Previously we reported a common activation pathway of the class A G protein-coupled receptors (GPCRs) in which a series of conserved residues/motifs undergo conformational change during extracellular agonist binding and finally induce the coupling of intracellular G protein, and successfully predicted several novel constitutive active or inactive mutations for A2A adenosine receptor (A2AAR) through this mechanism (Zhou et al., 2019). Here we determined the crystal structure of a typical A2AAR constitutive active mutant I92N in complex with agonist UK-432097 to reveal the molecular mechanism of mutation-induced constitutive activity. The mutated I92N forms a hydrophilic interaction network with nearby residues including W6.48 of the CWxP motif, which is absent in the wild type A2AAR. Although the mutant structure is overall similar to the previously determined intermediate state A2AAR structure (PDB ID: 3QAK), the molecular dynamics simulations suggested that the I92N mutant stabilizes the metastable intermediate state through the hydrophilic interaction network and favors the receptor conformational transition towards the active state. This research provides a structural template toward the special pharmacological outcome triggered by conformational mutation and sheds light on future structural or pharmacological studies among class A GPCRs.

molecular biology↗

Characterization of glucosyltransferase and glucuronosyltransferase family members reveals how major flavone glycoside accumulate in the root of Scutellaria baicalensis

Flavonoid glycosides extracted from roots of Scutellaria baicalensis exhibit strong pharmaceutical effect in antitumor, antioxidative, anti-inflammatory, and antiviral activity. UDP glycosyltransferase family members are responsible for the transfer of a glycosyl moiety from UDP sugars to a wide range of acceptor flavonoids. Here, we report the phylogenetic analysis, tissue-specific expression and biochemical characterization of 10 glucosyltrasferases (SbUGTs) and 6 glucuronosyltransferases (SbUGATs) based on the recently released genome of S. baicalensis. These results reveal that the high expression level and affinity to substrate of SbUGAT4 make baicalin become the richest flavonoid glycoside in the root of S. baicalensis.

plant biology↗

Injectable Progranulin-derivative Atsttrin loaded Protein Engineered Gels for Post Traumatic Osteoarthritis

Protein-based biomaterials offer several advantages over synthetic materials, owing to their unique stimuli-responsive properties, biocompatibility and modular nature. We have successfully developed protein block polymers that consist of elastin like polypeptide (E) and the coiled-coil domain of cartilage oligomeric matrix protein (C). Here, we demonstrate that E5C, a construct consisting of five repeats of E and a single domain of C, is capable of forming a porous networked gel at physiological temperature, making it an excellent candidate for injectable biomaterials. Combination of E5C with Atsttrin, a chondroprotective engineered derivative of anti-inflammatory growth factor progranulin (PGRN), provides a unique biochemical and biomechanical environment to protect against post-traumatic osteoarthritis (PTOA) onset and progression. E5C gel was demonstrated to provide prolonged release of Atsttrin and inhibit chondrocyte catabolism while facilitating anabolic signaling in vitro. We also provide in vivo evidence that prophylactic and therapeutic application of Atsttrin-loaded E5C hydrogels protected against PTOA onset and progression in a rabbit anterior cruciate ligament transection model. Collectively, we have developed a unique protein-based gel capable of minimally invasive, sustained delivery of prospective therapeutics, particularly the PGRN-derivative Atsttrin, for prevention of OA onset and progression.

bioengineering↗

High resolution ultrasonic neural modulation observedvia in vivo two-photon calcium imaging

Neural modulation plays a major role in delineating the circuit mechanisms and serves as the cornerstone of neural interface technologies. Among the various modulation mechanisms, ultrasound enables noninvasive label-free deep access to mammalian brain tissue. To date, most if not all ultrasonic neural modulation implementations are based on [~]1 MHz carrier frequency. The long acoustic wavelength results in a spatially coarse modulation zone, often spanning over multiple function regions. The modulation of one brain region is inevitably linked with the modulation of its neighboring regions. To significantly increase the spatial resolution, we explored the application of high-frequency ultrasound. To investigate the neuronal response at cellular resolutions, we developed a dual-modality system combining in vivo two-photon calcium imaging and focused ultrasound modulation. The studies show that the [~]30 MHz ultrasound can suppress the neuronal activity in awake mice at 100-micron scale spatial resolutions, paving the way for high-resolution ultrasonic neural modulation.

bioengineering↗

Amotosalen is a bacterial multidrug efflux pump substrate potentially affecting its pathogen inactivation activity

Pathogen inactivation is a strategy to improve the safety of transfusion products. The Cerus Intercept technology makes use of a psoralen compound called amotosalen in combination with UVA light to inactivate bacteria, viruses and protozoa. Psoralens have structural similarity to bacterial multidrug-efflux pump substrates. As these efflux pumps are often overexpressed in multidrug-resistant pathogens and with recent reported outbreaks of transfusion-associated sepsis with Acinetobacter, we tested whether contemporary drug-resistant pathogens might show resistance to amotosalen and other psoralens based on multidrug efflux mechanisms through microbiological, biophysical and molecular modeling analysis. The main efflux systems in Enterobacterales and Acinetobacter baumannii, tripartite RND (resistance-nodulation-cell division) systems which span the inner and outer membranes of Gram-negative pathogens and expel antibiotics from the bacterial cytoplasm into the extracellular space, were specifically examined. We found that amotosalen was an efflux substrate for the TolC-dependent RND efflux pumps in E. coli and the AdeABC efflux pump from Acinetobacter baumannii, and that minimal inhibitory concentrations for contemporary bacterial isolates in vitro approached and exceeded the concentration of amotosalen used in the approved platelet and plasma inactivation procedures. These findings suggest that otherwise safe and effective inactivation methods should be further studied to exclude possible gaps in their ability to inactivate contemporary, multidrug-resistant bacterial pathogens. ImportancePathogen inactivation is a strategy to enhance the safety of transfused blood products. We identify the compound, amotosalen, widely used for pathogen inactivation, as a bacterial multidrug efflux substrate. Specifically, experiments suggest that amotosalen is pumped out of bacteria by the major TolC-dependent RND efflux pumps in E. coli and the AdeABC efflux pump in Acinetobacter baumannii. Such efflux pumps are often overexpressed in multidrug-resistant pathogens. Importantly, the minimal inhibitory concentrations for contemporary multidrug-resistant Enterobacterales, Acinetobacter baumannii, Pseudomonas aeruginosa, Burkholderia spp., and Stenotrophomonas maltophilia isolates approached or exceeded the amotosalen concentration used in approved platelet and plasma inactivation procedures, potentially as a result of efflux pump activity. Although there are important differences in methodology between our experiments and blood product pathogen inactivation, these findings suggest that otherwise safe and effective inactivation methods should be further studied to exclude possible gaps in their ability to inactivate contemporary, multidrug-resistant bacterial pathogens.

microbiology↗

Identification of novel bat coronaviruses sheds light on the evolutionary origins of SARS-CoV-2 and related viruses

Although a variety of SARS-CoV-2 related coronaviruses have been identified, the evolutionary origins of this virus remain elusive. We describe a meta-transcriptomic study of 411 samples collected from 23 bat species in a small (~1100 hectare) region in Yunnan province, China, from May 2019 to November 2020. We identified coronavirus contigs in 40 of 100 sequencing libraries, including seven representing SARS-CoV-2-like contigs. From these data we obtained 24 full-length coronavirus genomes, including four novel SARS-CoV-2 related and three SARS-CoV related genomes. Of these viruses, RpYN06 exhibited 94.5% sequence identity to SARS-CoV-2 across the whole genome and was the closest relative of SARS-CoV-2 in the ORF1ab, ORF7a, ORF8, N, and ORF10 genes. The other three SARS-CoV-2 related coronaviruses were nearly identical in sequence and clustered closely with a virus previously identified in pangolins from Guangxi, China, although with a genetically distinct spike gene sequence. We also identified 17 alphacoronavirus genomes, including those closely related to swine acute diarrhea syndrome virus and porcine epidemic diarrhea virus. Ecological modeling predicted the co-existence of up to 23 Rhinolophus bat species in Southeast Asia and southern China, with the largest contiguous hotspots extending from South Lao and Vietnam to southern China. Our study highlights both the remarkable diversity of bat viruses at the local scale and that relatives of SARS-CoV-2 and SARS-CoV circulate in wildlife species in a broad geographic region of Southeast Asia and southern China. These data will help guide surveillance efforts to determine the origins of SARS-CoV-2 and other pathogenic coronaviruses.

microbiology↗

The VTA-BLA-NAc circuit for sex reward inhibited by VTA GABAergic neurons under stress in male mice

Anhedonia, inability to experience pleasure from rewarding or enjoyable activities, is the prominent symptom of depression that involves dysfunction of the reward processing system. Both genetic predisposition and life events are thought to increase the risk for depression, in particular life stress. The cellular mechanism underlying stress modulating the reward processing neural circuits and subsequently disrupting reward-related behaviors remains elusive. We identify the VTA-BLA-NAc pathway as being activated by sex reward. Blockade of this circuit induces depressive-like behaviors, while reactivation of VTA neurons associated with sexual rewarding experience acutely ameliorates the impairment of reward-seeking behaviors induced by chronic restraint stress. Our histological and electrophysiological results show that the VTA neuron subpopulation responding to restraint stress inhibits the responsiveness of the VTA dopaminergic neurons to sexual reward. Together, these results reveal the cellular mechanism by which stress influences the brain reward processing system and provide a potential target for depression treatment.

neuroscience↗

Clear optically matched panoramic access channel technique (COMPACT) for large-volume deep brain imaging

To understand neural circuit mechanisms underlying behavior, it is crucial to observe the dynamics of neuronal structure and function in different parts of the brain. Current imaging technologies allow cellular resolution imaging of neurons within ~1 millimeter below the cortical surface. Even for mice, the majority of brain tissue remains inaccessible. Although miniature optical imaging probes allow the access of deep brain regions, the cellular-resolution imaging is restricted to a small tissue volume. To drastically increase the tissue access volume and enable a high-throughput neurophotonic interface, we developed a clear optically matched panoramic access channel technique (COMPACT). With comparable probe dimension, COMPACT enables a two to three orders of magnitude greater tissue access volume for structural and function imaging. Leveraging the large-volume imaging capability of COMPACT, we demonstrated multiregional calcium imaging of deep brain functions associated with sleep for the first time. The compatibility of COMPACT for longitudinal large-volume in vivo imaging will be highly valuable to a variety of deep tissue imaging applications.

bioengineering↗

Probing neuronal functions with precise and targeted laser ablation in the living cortex

Targeted cell ablation is an important strategy for dissecting the function of individual cells within biological tissues. Here we developed an amplified femtosecond laser-coupled two-photon microscopy (AFL-TPM) system that allows instantaneous and targeted ablation of individual cells and real-time monitoring of neuronal network changes in the living mouse cortex. Through precise and iterative control of the laser power and position, individual cells could be ablated by a single femtosecond light pulse with minimum collateral damage. We further show that ablation of individual somatostatin-expressing interneuron increases the activity of nearby neurons in the primary motor cortex during motor learning. Through precise dendrotomy, we reveal that different dendritic branches of layer 5 pyramidal neurons are structurally and functionally independent. By ablating individual cells and their processes in a spatiotemporally specific manner, the AFL-TPM system could serve as an important means for understanding the functions of cells within the complicated neuronal network.

neuroscience↗

The genome analysis of Tripterygium wilfordii reveals TwCYP712K1 and TwCYP712K2 responsible for oxidation of friedelin in celastrol biosynthesis pathway

ABSTRACTTripterygium wilfordii is a Traditional Chinese Medicine (TCM) from family Celastraceae and celastrol is one of the strongest active ingredients belonging to friedelane-type pentacyclic triterpenoid, which has a large clinical application value of anti-tumor, immunosuppression, and obesity treatment. The first committed biosynthesis step of celastrol is the cyclization of 2, 3-oxidosqualene to friedelin, catalyzed by the oxidosqualene cyclase, while the rest of this pathway is still unclear. In this study, we reported a reference genome assembly of T. wilfordii with high-quality annotation by using a hybrid sequencing strategy (Nanopore, Bionano, Illumina HiSeq, and Pacbio), which obtained a 340.12 Mb total size and contig N50 reached 3.09 Mb. In addition, we successfully anchored 91.02% sequences into 23 pseudochromosomes using Hi-C technology and the super-scaffold N50 reached 13.03 Mb. Based on integration genome, transcriptom and metabolite analyses, as well as in vivo and in vitro enzyme assays, two CYP450 genes, TwCYP712K1 and TwCYP712K2 have been proven for C-29 position oxidation of friedelin to produce polpunonic acid, which clarifies the second biosynthesis step of celastrol. Syntenic analysis revealed that TwCYP712K1 and TwCYP712K2 derived from the common ancestor. These results have provided insight into illustrating pathways for both celastrol and other bioactive compounds found in this plant.Competing Interest StatementThe authors have declared no competing interest.View Full Text

plant biology↗

Requirement and functional redundancy of two large ribonucleotide reductase subunit genes for cell cycle, chloroplast biogenesis in tomato

Ribonucleotide reductase (RNR), functioning in the de novo synthesis of dNTPs, is crucial for DNA replication and cell cycle progression. However, the knowledge about the RNR in plants is still limited. In this study, we isolated ylc1 (young leaf chlorosis 1) mutant, which exhibited many development defects such as dwarf stature, chlorotic young leaf, and smaller fruits. Map-based cloning, complementation, and knocking-out experiments confirmed that YLC1 encodes a large subunit of RNR (SlRNRL1), an enzyme involved in the de novo biosynthesis of dNTPs. Physiological and transcriptomic analyses indicate that SlRNRL1 plays a crucial role in the regulation of cell cycle, chloroplast biogenesis, and photosynthesis in tomato. In addition, we knocked out SlRNRL2 (a SlRNRL1 homolog) using CRISPR-Cas9 technology in the tomato genome, and found that SlRNRL2, possessing a redundant function with SlRNRL1, played a weak role in the formation of RNR complex due to its low expression intensity. Genetic analysis reveals that SlRNRL1 and SlRNRL2 are essential for tomato growth and development as the double mutant slrnrl1slrnrl2 is lethal. This also implies that the de novo synthesis of dNTPs is required for seed development in tomato. Overall, our results provide a new insight for understanding the SlRNRL1 and SlRNRL2 functions and the mechanism of de novo biosynthesis of dNTPs in plants.

developmental biology↗

Bayesian estimation on logarithmic scales as an explanation for spatiotemporal interferences with a tendency of deceleration

Spatial and temporal information processing interfere with each other. Kappa effect is a famous spatiotemporal interference, in which the estimated time between two lights increases as an increase of distance between the lights, showing a tendency of deceleration. A classical model attributes the interference to constant speeds and predicts a linear relation, whereas a slowness model attributes the interference to slow speeds and proposes the tendency is the result of the variance of stimuli locations. The present study developed a logarithmic version of the classical model and asserts that the tendency is the result of the Web-Fechner law. These hypotheses were tested in two time discrimination tasks by manipulating the variance of stimuli locations and distance between stimuli. The results demonstrate that estimated time was not modulated by the variance of stimuli locations, and increased as an increase of distance with a tendency of deceleration. The Bayesian model on logarithmic scales made more accurate behavioral predictions than the linear model; the estimated constant speed of the logarithmic Bayesian model was equal to the absolute threshold of speed; the strength of the Kappa effect positively correlated with the variability of time perception. Findings suggest that the interference in the Kappa effect is driven by slow speeds, the strength of the interference is influenced by the variability of time perception, and the tendency of deceleration is the result of the Weber-Fechner law. This Bayesian framework may be useful when applied in the field of time perception and other types of cross-dimensional interferences.

neuroscience↗

Sort-purification of human CD34+CD90+ cells reduces target cell population and improves lentiviral transduction

ABSTRACTHematopoietic stem cell (HSC) gene therapy has the potential to cure many genetic, malignant and infectious diseases. We have shown in a nonhuman primate (NHP) HSC gene therapy and transplantation model that the CD34+CD90+ cell fraction was exclusively responsible for multilineage engraftment and hematopoietic reconstitution. Here we show the translational potential of this HSC-enriched CD34 subset for lentivirus-mediated gene therapy. Alternative HSC-enrichment strategies include the purification of CD133+ cells or CD38low/- subsets of CD34+ cells from human blood products. We directly compared these strategies to the isolation of CD90+ cells using a GMP-grade flow-sorting protocol with clinical applicability. We show that CD90+ cell selection results in 40-fold fewer target cells in comparison to CD133+ or CD38low/- CD34 subsets without compromising the engraftment potential in vivo. Single cell RNA sequencing confirmed nearly complete depletion of lineage committed progenitor cells in CD90+ fractions compared to alternative selections. Importantly, lentiviral transduction efficiency in purified CD90+ cells resulted in up to 3-fold higher levels of engrafted gene-modified blood cells. These studies should have important implications for the manufacturing of patient-specific HSC gene therapy and genome editing products.

cell biology↗