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1.
Adv Mater ; : e2405519, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801117

RESUMO

Pushing intercalation-type cathode materials to their theoretical capacity often suffers from fragile Li-deficient frameworks and severe lattice strain, leading to mechanical failure issues within the crystal structure and fast capacity fading. This is particularly pronounced in layered oxide cathodes because the intrinsic nature of their structures is susceptible to structural degradation with excessive Li extraction, which remains unsolved yet despite attempts involving elemental doping and surface coating strategies. Herein, a mechanochemical strengthening strategy is developed through a gradient disordering structure to address these challenges and push the LiCoO2 (LCO) layered cathode approaching the capacity limit (256 mAh g-1, up to 93% of Li utilization). This innovative approach also demonstrates exceptional cyclability and rate capability, as validated in practical Ah-level pouch full cells, surpassing the current performance benchmarks. Comprehensive characterizations with multiscale X-ray, electron diffraction, and imaging techniques unveil that the gradient disordering structure notably diminishes the anisotropic lattice strain and exhibits high fatigue resistance, even under extreme delithiation states and harsh operating voltages. Consequently, this designed LCO cathode impedes the growth and propagation of particle cracks, and mitigates irreversible phase transitions. This work sheds light on promising directions toward next-generation high-energy-density battery materials through structural chemistry design.

2.
Science ; 384(6698): 885-890, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38781365

RESUMO

Men or mice with homozygous serine/threonine kinase 33 (STK33) mutations are sterile owing to defective sperm morphology and motility. To chemically evaluate STK33 for male contraception with STK33-specific inhibitors, we screened our multibillion-compound collection of DNA-encoded chemical libraries, uncovered potent STK33-specific inhibitors, determined the STK33 kinase domain structure bound with a truncated hit CDD-2211, and generated an optimized hit CDD-2807 that demonstrates nanomolar cellular potency (half-maximal inhibitory concentration = 9.2 nanomolar) and favorable metabolic stability. In mice, CDD-2807 exhibited no toxicity, efficiently crossed the blood-testis barrier, did not accumulate in brain, and induced a reversible contraceptive effect that phenocopied genetic STK33 perturbations without altering testis size. Thus, STK33 is a chemically validated, nonhormonal contraceptive target, and CDD-2807 is an effective tool compound.


Assuntos
Anticoncepção , Anticoncepcionais Masculinos , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Bibliotecas de Moléculas Pequenas , Animais , Humanos , Masculino , Camundongos , Barreira Hematotesticular/metabolismo , Anticoncepcionais Masculinos/química , Anticoncepcionais Masculinos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Testículo/efeitos dos fármacos , Anticoncepção/métodos , Relação Estrutura-Atividade
3.
BMC Bioinformatics ; 25(1): 29, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233783

RESUMO

The impairment of sperm maturation is one of the major pathogenic factors in male subfertility, a serious medical and social problem affecting millions of global couples. Regrettably, the existing research on sperm maturation is slow, limited, and fragmented, largely attributable to the lack of a global molecular view. To fill the data gap, we newly established a database, namely the Sperm Maturation Database (SperMD, http://bio-add.org/SperMD ). SperMD integrates heterogeneous multi-omics data (170 transcriptomes, 91 proteomes, and five human metabolomes) to illustrate the transcriptional, translational, and metabolic manifestations during the entire lifespan of sperm maturation. These data involve almost all crucial scenarios related to sperm maturation, including the tissue components of the epididymal microenvironment, cell constituents of tissues, different pathological states, and so on. To the best of our knowledge, SperMD could be one of the limited repositories that provide focused and comprehensive information on sperm maturation. Easy-to-use web services are also implemented to enhance the experience of data retrieval and molecular comparison between humans and mice. Furthermore, the manuscript illustrates an example application demonstrated to systematically characterize novel gene functions in sperm maturation. Nevertheless, SperMD undertakes the endeavor to integrate the islanding omics data, offering a panoramic molecular view of how the spermatozoa gain full reproductive abilities. It will serve as a valuable resource for the systematic exploration of sperm maturation and for prioritizing the biomarkers and targets for precise diagnosis and therapy of male subfertility.


Assuntos
Infertilidade Masculina , Maturação do Esperma , Masculino , Humanos , Animais , Camundongos , Maturação do Esperma/genética , Sêmen , Espermatozoides/metabolismo , Epididimo/metabolismo , Infertilidade Masculina/metabolismo
4.
Nat Mater ; 23(2): 244-251, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38191629

RESUMO

Interface reaction between lithium (Li) and materials at the anode is not well understood in an all-solid environment. This paper unveils a new phenomenon of constriction susceptibility for materials at such an interface, the utilization of which helps facilitate the design of an active three-dimensional scaffold to host rapid plating and stripping of a significant amount of a thick Li metal layer. Here we focus on the well-known anode material silicon (Si) to demonstrate that, rather than strong Li-Si alloying at the conventional solid-liquid interface, the lithiation reaction of micrometre-sized Si can be significantly constricted at the solid-solid interface so that it occurs only at thin surface sites of Si particles due to a reaction-induced, diffusion-limiting process. The dynamic interaction between surface lithiation and Li plating of a family of anode materials, as predicted by our constrained ensemble computational approach and represented by Si, silver (Ag) and alloys of magnesium (Mg), can thus more homogeneously distribute current densities for the rapid cycling of Li metal at high areal capacity, which is important in regard to solid-state battery application.

5.
Adv Mater ; 36(6): e2307404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37870392

RESUMO

The rapid development of modern consumer electronics is placing higher demands on the lithium cobalt oxide (LiCoO2 ; LCO) cathode that powers them. Increasing operating voltage is exclusively effective in boosting LCO capacity and energy density but is inhibited by the innate high-voltage instability of the LCO structure that serves as the foundation and determinant of its electrochemical behavior in lithium-ion batteries. This has stimulated extensive research on LCO structural stabilization. Here, it is focused on the fundamental structural understanding of LCO cathode from long-term studies. Multi-scale structures concerning LCO bulk and surface and various structural issues along with their origins and corresponding stabilization strategies with specific mechanisms are uncovered and elucidated at length, which will certainly deepen and advance the knowledge of LCO structure and further its inherent relationship with electrochemical performance. Based on these understandings, remaining questions and opportunities for future stabilization of the LCO structure are also emphasized.

6.
Hum Reprod ; 39(2): 310-325, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38011909

RESUMO

STUDY QUESTION: What is the mechanism behind cryoinjury in human sperm, particularly concerning the interplay between reactive oxygen species (ROS) and autophagy, and how does it subsequently affect sperm fate? SUMMARY ANSWER: The freeze-thaw operation induces oxidative stress by generating abundant ROS, which impairs sperm motility and activates autophagy, ultimately guiding the sperm toward programmed cell death such as apoptosis and necrosis, as well as triggering premature capacitation. WHAT IS KNOWN ALREADY: Both ROS-induced oxidative stress and autophagy are thought to exert an influence on the quality of frozen-thawed sperm. STUDY DESIGN, SIZE, DURATION: Overall, 84 semen specimens were collected from young healthy fertile males, with careful quality evaluation. The specimens were split into three groups to investigate the ROS-induced cryoinjury: normal control without any treatment, sperm treated with 0.5 mM hydrogen peroxide (H2O2) for 1 h, and sperm thawed following cryopreservation. Samples from 48 individuals underwent computer-assisted human sperm analysis (CASA) to evaluate sperm quality in response to the treatments. Semen samples from three donors were analyzed for changes in the sperm proteome after H2O2 treatment, and another set of samples from three donors were analyzed for changes following the freeze-thaw process. The other 30 samples were used for fluorescence-staining and western blotting. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm motility parameters, including progressive motility (PR %) and total motility (PR + NP %), were evaluated using the CASA system on a minimum of 200 spermatozoa. The proteomic profiles were determined with label-free mass spectrometry (MS/MS) and protein identification was performed via ion search against the NCBI human database. Subsequently, comprehensive bioinformatics was applied to detect significant proteomic changes and functional enrichment. Fluorescence-staining and western blot analyses were also conducted to confirm the proteomic changes on selected key proteins. The ROS level was measured using 2',7'-dichlorodihydrofluorescein diacetate labeling and the abundance of bioactive mitochondria was determined by evaluating the inner mitochondrial membrane potential (MMP) level. Molecular behaviors of sequestosome-1 (p62 or SQSTM1) and microtubule-associated proteins 1A/1B light chain 3 (LC3) were monitored to evaluate the state of apoptosis in human sperm. Fluorescent probes oxazole yellow (YO-PRO-1) and propidium iodide (PI) were utilized to monitor programmed cell death, namely apoptosis and necrosis. Additionally, gradient concentrations of antioxidant coenzyme Q10 (CoQ10) were introduced to suppress ROS impacts on sperm. MAIN RESULTS AND THE ROLE OF CHANCE: The CASA analysis revealed a significant decrease in sperm motility for both the H2O2-treatment and freeze-thaw groups. Fluorescence staining showed that high ROS levels were produced in the treated sperm and the MMPs were largely reduced. The introduction of CoQ10 at concentrations of 20 and 30 µM resulted in a significant rescue of progressive motility (P < 0.05). The result suggested that excessive ROS could be the major cause of sperm motility impairment, likely by damaging mitochondrial energy generation. Autophagy was significantly activated in sperm when they were under oxidative stress, as evidenced by the upregulation of p62 and the increased conversion of LC3 as well as the upregulation of several autophagy-related proteins, such as charged multivesicular body protein 2a, mitochondrial import receptor subunit TOM22 homolog, and WD repeat domain phosphoinositide-interacting protein 2. Additionally, fluorescent staining indicated the occurrence of apoptosis and necrosis in both H2O2-treated sperm and post-thaw sperm. The cell death process can be suppressed when CoQ10 is introduced, which consolidates the view that ROS could be the major contributor to sperm cryoinjury. The freeze-thaw process could also initiate sperm premature capacitation, demonstrated by the prominent increase in tyrosine phosphorylated proteins, verified with anti-phosphotyrosine antibody and immunofluorescence assays. The upregulation of capacitation-related proteins, such as hyaluronidase 3 and Folate receptor alpha, supported this finding. LARGE SCALE DATA: The data underlying this article are available in the article and its online supplementary material. LIMITATIONS, REASONS FOR CAUTION: The semen samples were obtained exclusively from young, healthy, and fertile males with progressive motility exceeding 60%, which might overemphasize the positive effects while possibly neglecting the negative impacts of cryoinjury. Additionally, the H2O2 treatment conditions in this study may not precisely mimic the oxidative stress experienced by sperm after thawing from cryopreservation, potentially resulting in the omission of certain molecular alterations. WIDER IMPLICATIONS OF THE FINDINGS: This study provides substantial proteomic data for a comprehensive and deeper understanding of the impact of cryopreservation on sperm quality. It will facilitate the design of optimal protocols for utilizing cryopreserved sperm to improve applications, such as ART, and help resolve various adverse situations caused by chemotherapy, radiotherapy, and surgery. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Major Innovation Project of Research Institute of National Health Commission (#2022GJZD01-3) and the National Key R&D Program of China (#2018YFC1003600). All authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides , Peróxido de Hidrogênio , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Estresse Oxidativo , Criopreservação/métodos , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Necrose/metabolismo
7.
IEEE J Biomed Health Inform ; 27(12): 5827-5836, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37751334

RESUMO

Research on orthodontic treatment monitoring from oralscan video is a new direction in dental digitalization. We designed an approach to reconstruct, segment, and estimate the pose of individual teeth to measure orthodontic treatment. To handle the semantic gap in heterogeneous data on the condition that they are combined linearly, we present a multimedia interaction network (MIN) to combine heterogeneous information in point cloud segmentation by extending the graph attention mechanism. Moreover, a structure-aware quadruple loss is designed to explore the relation between multiple and diverse unmatched points in point cloud registration. The performance of our approach is evaluated on multiple tooth registration datasets, and extensive experiments show that our approach improves the accuracy by a margin of 1.4% in the inlier ratio on the Aoralscan3 dataset when it is compared with prevailing approaches.


Assuntos
Ortodontia , Dente , Gravação em Vídeo , Humanos , Dente/diagnóstico por imagem
8.
Commun Chem ; 6(1): 164, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542196

RESUMO

The development of SARS-CoV-2 main protease (Mpro) inhibitors for the treatment of COVID-19 has mostly benefitted from X-ray structures and preexisting knowledge of inhibitors; however, an efficient method to generate Mpro inhibitors, which circumvents such information would be advantageous. As an alternative approach, we show here that DNA-encoded chemistry technology (DEC-Tec) can be used to discover inhibitors of Mpro. An affinity selection of a 4-billion-membered DNA-encoded chemical library (DECL) using Mpro as bait produces novel non-covalent and non-peptide-based small molecule inhibitors of Mpro with low nanomolar Ki values. Furthermore, these compounds demonstrate efficacy against mutant forms of Mpro that have shown resistance to the standard-of-care drug nirmatrelvir. Overall, this work demonstrates that DEC-Tec can efficiently generate novel and potent inhibitors without preliminary chemical or structural information.

9.
Genes (Basel) ; 14(6)2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37372344

RESUMO

Lactation initiation refers to a functional change in the mammary organ from a non-lactating state to a lactating state, and a series of cytological changes in the mammary epithelium from a non-secreting state to a secreting state. Like the development of the mammary gland, it is regulated by many factors (including hormones, cytokines, signaling molecules, and proteases). In most non-pregnant animals, a certain degree of lactation also occurs after exposure to specific stimuli, promoting the development of their mammary glands. These specific stimuli can be divided into two categories: before and after parturition. The former inhibits lactation and decreases activity, and the latter promotes lactation and increases activity. Here we present a review of recent progress in research on the key factors of lactation initiation to provide a powerful rationale for the study of the lactation initiation process and mammary gland development.


Assuntos
Hormônios , Lactação , Gravidez , Feminino , Animais , Bovinos , Lactação/fisiologia , Transdução de Sinais , Parto , Glândulas Mamárias Animais
10.
Commun Biol ; 6(1): 214, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823181

RESUMO

Spermatogenesis is an extremely complex process, and any obstruction can cause male infertility. RhoGDIα has been identified as a risk of male sterility. In this study, we generate RhoGDIα knockout mice, and find that the males have severely low fertility. The testes from RhoGDIα-/- mice are smaller than that in WT mice. The numbers of spermatogonia and spermatocytes are decreased in RhoGDIα-/- testis. Spermatogenesis is compromised, and spermatocyte meiosis is arrested at zygotene stage in RhoGDIα-/- mice. Acrosome dysplasia is also observed in sperms of the mutant mice. At the molecular level, RhoGDIα deficiency activate the LIMK/cofilin signaling pathway, inhibiting F-actin depolymerization, impairing testis and inducing low fertility in mouse. In addition, the treatment of RhoGDIα-/- mice with Rac1 inhibitor NSC23766 alleviate testis injury and improve sperm quality by inhibiting the LIMK/cofilin/F-actin pathway during spermatogenesis. Together, these findings reveal a previously unrecognized RhoGDIα/Rac1/F-actin-dependent mechanism involved in spermatogenesis and male fertility.


Assuntos
Actinas , Infertilidade Masculina , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho , Animais , Masculino , Camundongos , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Infertilidade Masculina/genética , Camundongos Knockout , Proteínas rac1 de Ligação ao GTP/genética , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/genética , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo , Sêmen/metabolismo , Transdução de Sinais/fisiologia , Espermatogênese
11.
J Med Chem ; 66(3): 2143-2160, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36719862

RESUMO

The discovery of monokinase-selective inhibitors for patients is challenging because the 500+ kinases encoded by the human genome share highly conserved catalytic domains. Until now, no selective inhibitors unique for a single transforming growth factor ß (TGFß) family transmembrane receptor kinase, including bone morphogenetic protein receptor type 2 (BMPR2), have been reported. This dearth of receptor-specific kinase inhibitors hinders therapeutic options for skeletal defects and cancer as a result of an overactivated BMP signaling pathway. By screening 4.17 billion "unbiased" and "kinase-biased" DNA-encoded chemical library molecules, we identified hits CDD-1115 and CDD-1431, respectively, that were low-nanomolar selective kinase inhibitors of BMPR2. Structure-activity relationship studies addressed metabolic lability and high-molecular-weight issues, resulting in potent and BMPR2-selective inhibitor analogs CDD-1281 (IC50 = 1.2 nM) and CDD-1653 (IC50 = 2.8 nM), respectively. Our work demonstrates that DNA-encoded chemistry technology (DEC-Tec) is reliable for identifying novel first-in-class, highly potent, and selective kinase inhibitors.


Assuntos
DNA , Transdução de Sinais , Humanos , Biblioteca Gênica , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/química , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo
12.
Life Sci ; 314: 121319, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36574945

RESUMO

Heat shock proteins (HSPs) have important roles in different developmental stages of spermatogenesis. The heat shock 70 kDa protein 5 (HSPA5) is an important component of the unfolded protein response that promotes cell survival under endoplasmic reticulum (ER) stress conditions. In this study, we explored the function of HSPA5 in spermatogenesis, by generating a germ cell-specific deletion mutant of the Hspa5 gene (conditional knockout of the Hspa5 gene, Hspa5-cKO) using CRISPR/Cas9 technology and the Cre/Loxp system. Hspa5 knockout resulted in severe germ cell loss and vacuolar degeneration of seminiferous tubules, leading to complete arrest of spermatogenesis, testicular atrophy, and male infertility in adult mice. Furthermore, defects occurred in the spermatogenic epithelium of Hspa5-cKO mice as early as Cre recombinase expression. Germ cell ablation of Hspa5 impaired spermatogonia proliferation and differentiation from post-natal day 7 (P7) to P10, which led to a dramatic reduction of differentiated spermatogonia, compromised meiosis, and led to impairment of testis development and the disruption of the first wave of spermatogenesis. Consistent with these results, single-cell RNA sequencing (scRNA-seq) analysis showed that germ cells, especially differentiated spermatogonia, were dramatically reduced in Hspa5-cKO testes compared with controls at P10, further confirming that HSPA5 is crucial for germ cell development. These results suggest that HSPA5 is indispensable for normal spermatogenesis and male reproduction in mice.


Assuntos
Infertilidade Masculina , Testículo , Masculino , Camundongos , Animais , Humanos , Camundongos Knockout , Testículo/metabolismo , Espermatogênese/genética , Espermatogônias/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo
13.
Andrology ; 11(5): 808-815, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36209044

RESUMO

BACKGROUND: A safe, effective, and reversible nonhormonal male contraceptive drug is greatly needed for male contraception as well as for circumventing the side effects of female hormonal contraceptives. Phosducin-like 2 (PDCL2) is a testis-specific phosphoprotein in mice and humans. We recently found that male PDCL2 knockout mice are sterile due to globozoospermia caused by impaired sperm head formation, indicating that PDCL2 is a potential target for male contraception. Herein, our study for the first time developed a biophysical assay for PDCL2 allowing us to screen a series of small molecules, to study structure-activity relationships, and to discover two PDCL2 binders with novel chemical structure. OBJECTIVE: To identify a PDCL2 ligand for therapeutic male contraception, we performed DNA-encoded chemical library (DECL) screening and off-DNA hit validation using a unique affinity selection mass spectrometry (ASMS) biophysical profiling strategy. MATERIALS AND METHODS: We employed the screening process of DECL, which contains billions of chemically unique DNA-barcoded compounds generated through individual sequences of reactions and different combinations of functionalized building blocks. The structures of the PDCL2 binders are proposed based on the sequencing analysis of the DNA barcode attached to each individual DECL compound. The proposed structure is synthesized through multistep reactions. To confirm and determine binding affinity between the DECL identified molecules and PDCL2, we developed an ASMS assay that incorporates liquid chromatography with tandem mass spectrometry (LC-MS/MS). RESULTS: After a screening process of PDCL2 with DECLs containing >440 billion compounds, we identified a series of hits. The selected compounds were synthesized as off-DNA small molecules, characterized by spectroscopy data, and subjected to our ASMS/LC-MS/MS binding assay. By this assay, we discovered two novel compounds, which showed good binding affinity for PDCL2 in comparison to other molecules generated in our laboratory and which were further confirmed by a thermal shift assay. DISCUSSION AND CONCLUSION AND RELEVANCE: With the ASMS/LC-MS/MS assay developed in this paper, we successfully discovered a PDCL2 ligand that warrants further development as a male contraceptive.


Assuntos
DNA , Bibliotecas de Moléculas Pequenas , Humanos , Masculino , Feminino , Animais , Camundongos , DNA/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Descoberta de Drogas , Ligantes , Cromatografia Líquida , Espectrometria de Massas em Tandem , Sêmen/metabolismo
14.
IEEE/ACM Trans Comput Biol Bioinform ; 20(4): 2506-2517, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36279353

RESUMO

Coronavirus disease-2019 (COVID-19) as a new pneumonia which is extremely infectious, the classification of this coronavirus is essential to effectively control the development of the epidemic. Pathological changes in the chest computed tomography (CT) scans are often used as one of the diagnostic criteria of COVID-19. Meanwhile, deep learning-based transfer learning is currently an effective strategy for computer-aided diagnosis (CAD). To further improve the performance of deep transfer learning model used for COVID-19 classification with CT images, in this article, we propose a hybrid model combined with a semi-supervised domain adaption model and extreme learning machine (ELM) classifier, and the application of a novel multikernel correntropy induced loss function in transfer learning is also presented. The proposed model is evaluated on open-source datasets. The experimental results are compared to some baseline models to verify the effectiveness, while adopting accuracy, precision, recall, F1 score and area under curve (AUC) as the evaluation metrics. Experimental results show that the proposed method improves the performance of original model and is more suitable for CT images analysis.

15.
PeerJ ; 10: e14472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518274

RESUMO

Spermatogenesis and sperm maturation are complex and highly ordered biological processes. Any failure or disorder in these processes can cause defects in sperm morphology, motility, and fertilization ability. Cathepsin B (CTSB) is involved in the regulation of a variety of pathological processes. In the present study, we found that CTSB was abundantly expressed in the male reproductive system, however, the specific role of CTSB in regulating spermatogenesis and sperm maturation remained elusive. Hence, we generated Ctsb -/- mice using CRISPR/Cas9 technology. In Ctsb -/- mice, sperm count was significantly decreased while the level of morphologically abnormal sperm was markedly increased. Additionally, these mice had significantly lower levels of progressive motility sperm and elevated levels of immobilized sperm. Histological analysis showed slight vacuolization in the testis epithelium, as well as the loss of epididymal epithelium cells. Further investigation showed that autophagic activity was inhibited and apoptotic activity was increased in both the testis and epididymis of Ctsb -/- mice. Together, our findings demonstrate that CTSB plays an important role in spermatogenesis and sperm maturation in mice.


Assuntos
Catepsina B , Espermatogênese , Animais , Masculino , Camundongos , Apoptose , Catepsina B/genética , Catepsina B/metabolismo , Sêmen , Maturação do Esperma
16.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35982227

RESUMO

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Masculino , Microscopia Crioeletrônica , Sulfato de Desidroepiandrosterona , Desoxicorticosterona , Ligantes , Receptores Acoplados a Proteínas G/química
17.
Folia Histochem Cytobiol ; 60(3): 226-236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35929062

RESUMO

INTRODUCTION: Peroxiredoxin 6 (Prdx6) is widely expressed in mammalian tissues. Our previous study demonstrated that Prdx6 was expressed in human epididymis, present in human seminal fluid, and in spermatozoa. The protective role of Prdx6 in maintaining the viability and DNA integrity of human spermatozoa was also detected. Here, we demonstrate the potential role and mechanism of Prdx6 in human epididymis epithelial cells (HEECs). MATERIAL AND METHODS: Western blotting was used to measure expression levels of key proteins in the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway. The malonaldehyde (MDA) levels and antioxidant capacity in HEECs were detected with the commercial kits. Digital gene expression analysis (DGE) was used to identify gene expression patterns in control and Prdx6-interference HEECs. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to validate the DGE findings. RESULTS: Compared to control HEECs, the expression levels of JAK1, STAT1, phosphorylated JAK1 and STAT1 were significantly increased, while the expression level of SOCS3 was significantly decreased in Prdx6-interference HEECs. The MDA level and total antioxidant capacity in Prdx6-interference HEECs were significantly increased and decreased compared to that of control, respectively. DGE analysis identified 589 up-regulated and 314 down-regulated genes (including Prdx6) in Prdx6-interference HEECs. Thirteen significantly different pathways were identified between the two groups, with the majority of genes belonging to the CCL, CXCL, IL, and IFIT family of proteins and were related to immunity. In particular, the expression levels of IL6, IL6ST, and eighteen IFN-related genes were significantly increased in Prdx6-interference HEECs compared to control HEECs. CONCLUSIONS: We found that reduced Prdx6 expression induced higher ROS levels in HEECs, which resulted in the activation of the IL-6 receptor and IFNγ expression to induce the JAK1/STAT1 signaling pathway.


Assuntos
Interleucina-6 , Peroxirredoxina VI , Antioxidantes , DNA , Epididimo/metabolismo , Células Epiteliais/metabolismo , Humanos , Interleucina-6/metabolismo , Janus Quinase 1 , Janus Quinases/metabolismo , Masculino , Malondialdeído , Peroxirredoxina VI/genética , Peroxirredoxina VI/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
18.
Adv Mater ; 34(30): e2202745, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35657036

RESUMO

The key to breaking through the capacity limitation imposed by intercalation chemistry lies in the ability to harness more active sites that can reversibly accommodate more ions (e.g., Li+ ) and electrons within a finite space. However, excessive Li-ion insertion into the Li layer of layered cathodes results in fast performance decay due to the huge lattice change and irreversible phase transformation. In this study, an ultrahigh reversible capacity is demonstrated by a layered oxide cathode purely based on manganese. Through a wealth of characterizations, it is clarified that the presence of low-content Li2 MnO3 domains not only reduces the amount of irreversible O loss; but also regulates Mn migration in LiMnO2 domains, enabling elastic lattice with high reversibility for tetrahedral sites Li-ion storage in Li layers. This work utilizes bulk cation disorder to create stable Li-ion-storage tetrahedral sites and an elastic lattice for layered materials, with a reversible capacity of 600 mA h g-1 , demonstrated in th range 0.6-4.9 V versus Li/Li+ at 10 mA g-1 . Admittedly, discharging to 0.6 V might be too low for practical use, but this exploration is still of great importance as it conceptually demonstrates the limit of Li-ions insertion into layered oxide materials.

19.
Natl Sci Rev ; 9(6): nwac028, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35677223

RESUMO

Recent decades have witnessed an exponential growth in the discovery of low-dimensional materials (LDMs), benefiting from our unprecedented capabilities in characterizing their structure and chemistry with the aid of advanced computational techniques. Recently, the success of two-dimensional compounds has encouraged extensive research into one-dimensional (1D) atomic chains. Here, we present a methodology for topological classification of structural blocks in bulk crystals based on graph theory, leading to the identification of exfoliable 1D atomic chains and their categorization into a variety of chemical families. A subtle interplay is revealed between the prototypical 1D structural motifs and their chemical space. Leveraging the structure graphs, we elucidate the self-passivation mechanism of 1D compounds imparted by lone electron pairs, and reveal the dependence of the electronic band gap on the cationic percolation network formed by connections between structure units. This graph-theory-based formalism could serve as a source of stimuli for the future design of LDMs.

20.
Front Plant Sci ; 13: 1098549, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36726676

RESUMO

Wheat leaf rust, caused by Puccinia triticina Eriks. (Pt), is a global wheat disease threatening wheat production. Dissecting how Pt effector proteins interact with wheat has great significance in understanding the pathogenicity mechanisms of Pt. In the study, the cDNA of Pt 13-5-72 interacting with susceptible cultivar Thatcher was used as template to amplify Pt13024 gene. The expression pattern and structure of Pt13024 were analyzed by qRT-PCR and online softwares. The secretion function of Pt13024 signal peptide was verified by the yeast system. Subcellular localization of Pt13024 was analyzed using transient expression on Nicotiana benthamiana. The verification that Pt13024 inhibited programmed cell death (PCD) was conducted on N. benthamiana and wheat. The deletion mutation of Pt13024 was used to identify the virulence function motif. The transient transformation of wheat mediated by the type III secretion system (TTSS) was used to analyze the activity of regulating the host defense response of Pt13024. Pt13024 gene silencing was performed by host-induced gene silencing (HIGS). The results showed that Pt13024 was identified as an effector and localized in the cytoplasm and nucleus on the N. benthamiana. It can inhibit PCD induced by the Bcl-2-associated X protein (BAX) from mice and infestans 1 (INF1) from Phytophthora infestans on N. benthamiana, and it can also inhibit PCD induced by DC3000 on wheat. The amino acids 22 to 41 at N-terminal of the Pt13024 are essential for the inhibition of programmed cell death (PCD) induced by BAX. The accumulation of reactive oxygen species and deposition of callose in near-isogenic line TcLr30, which is in Thatcher background with Lr30, induced by Pt13024 was higher than that in 41 wheat leaf rust-resistant near-isogenic lines (monogenic lines) with different resistance genes and Thatcher. Silencing of Pt13024 reduced the leaf rust resistance of Lr30 during the interaction between Pt and TcLr30. We can conclude that Pt13024 is avirulent to TcLr30 when Pt interacts with TcLr30. These findings lay the foundation for further investigations into the role of Pt effector proteins in pathogenesis and their regulatory mechanisms.

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