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1.
J Coll Physicians Surg Pak ; 34(5): 527-532, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720211

RESUMEN

OBJECTIVE: To develop an intervention based on Notch-1 signalling pathway blockade by investigating the potential application of the neurogenic locus notch homologue protein 1(Notch-1) signalling pathway as a key regulator of chronic inflammation and adipogenesis in the treatment of hepatic insulin resistance (HIR). STUDY DESIGN: Experimental study. Place and Duration of the Study: Animal Laboratory of the Fourth Hospital of Hebei Medical University, Shijiazhuang, China, from April 2021 to June 2022. METHODOLOGY: HIR models were established in Notch-1WT and Notch-1MAC-KO mice by high fat diet (HFD) for 16 weeks. Haematoxylin and eosin (HE) staining and oil red O (ORO) staining were used to detect inflammatory infiltration and lipid accumulation in each group. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of TNF-α and IL-6. Free fatty acid (FFA) and total cholesterol (TC) were measured with relevant kits. Moreover, real-time quantitative polymerase chain reaction (PCR) was performed to detect the relative expressions of F4/80, Mcp1, and CD11b in hepatic tissues. Mass spectrometry was used to analyse the levels of triglyceride (TG), diacylglycerol (DAG) and conformite europeenne (CE) in liver tissue. Western blotting was used to detect the expression of related proteins. RESULTS: Specific knockdown of Notch-1 in macrophages decreases the relative fluorescence intensity of CD68 and attenuates inflammatory infiltration and lipid degeneration. There was no difference in plasma levels of FFA and TG. Specific knockdown of Notch-1 in macrophages decreases the expression of F4/80, Mcp1, and CD11b, as well as the levels of TG, DAG, CE, IL-6, and TNF-α. CONCLUSION: Specific knockout of Notch-1 in macrophages may reduce HIR by inhibiting the IRE1α-XBP1 signalling pathway. KEY WORDS: Hepatic insulin resistance, Macrophages, Notch-1, IRE1α, XBP1.


Asunto(s)
Dieta Alta en Grasa , Resistencia a la Insulina , Macrófagos , Ratones Noqueados , Proteínas Serina-Treonina Quinasas , Receptor Notch1 , Transducción de Señal , Animales , Ratones , Modelos Animales de Enfermedad , Endorribonucleasas/metabolismo , Endorribonucleasas/genética , Resistencia a la Insulina/fisiología , Hígado/metabolismo , Macrófagos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Notch1/metabolismo , Receptor Notch1/genética , Proteína 1 de Unión a la X-Box/metabolismo , Proteína 1 de Unión a la X-Box/genética
2.
Cell ; 187(6): 1440-1459.e24, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38490181

RESUMEN

Following the fertilization of an egg by a single sperm, the egg coat or zona pellucida (ZP) hardens and polyspermy is irreversibly blocked. These events are associated with the cleavage of the N-terminal region (NTR) of glycoprotein ZP2, a major subunit of ZP filaments. ZP2 processing is thought to inactivate sperm binding to the ZP, but its molecular consequences and connection with ZP hardening are unknown. Biochemical and structural studies show that cleavage of ZP2 triggers its oligomerization. Moreover, the structure of a native vertebrate egg coat filament, combined with AlphaFold predictions of human ZP polymers, reveals that two protofilaments consisting of type I (ZP3) and type II (ZP1/ZP2/ZP4) components interlock into a left-handed double helix from which the NTRs of type II subunits protrude. Together, these data suggest that oligomerization of cleaved ZP2 NTRs extensively cross-links ZP filaments, rigidifying the egg coat and making it physically impenetrable to sperm.


Asunto(s)
Glicoproteínas de la Zona Pelúcida , Humanos , Masculino , Semen , Espermatozoides/química , Espermatozoides/metabolismo , Zona Pelúcida/química , Zona Pelúcida/metabolismo , Glicoproteínas de la Zona Pelúcida/química , Glicoproteínas de la Zona Pelúcida/metabolismo , Óvulo/química , Óvulo/metabolismo , Femenino
3.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38261343

RESUMEN

Cryo-Electron Microscopy (cryo-EM) is a widely used and effective method for determining the three-dimensional (3D) structure of biological molecules. For ab-initio Cryo-EM 3D reconstruction using single particle analysis (SPA), estimating the projection direction of the projection image is a crucial step. However, the existing SPA methods based on common lines are sensitive to noise. The error in common line detection will lead to a poor estimation of the projection directions and thus may greatly affect the final reconstruction results. To improve the reconstruction results, multiple candidate common lines are estimated for each pair of projection images. The key problem then becomes a combination optimization problem of selecting consistent common lines from multiple candidates. To solve the problem efficiently, a physics-inspired method based on a kinetic model is proposed in this work. More specifically, hypothetical attractive forces between each pair of candidate common lines are used to calculate a hypothetical torque exerted on each projection image in the 3D reconstruction space, and the rotation under the hypothetical torque is used to optimize the projection direction estimation of the projection image. This way, the consistent common lines along with the projection directions can be found directly without enumeration of all the combinations of the multiple candidate common lines. Compared with the traditional methods, the proposed method is shown to be able to produce more accurate 3D reconstruction results from high noise projection images. Besides the practical value, the proposed method also serves as a good reference for solving similar combinatorial optimization problems.


Asunto(s)
Imagenología Tridimensional , Microscopía por Crioelectrón , Cinética
4.
Exp Anim ; 73(1): 1-10, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-37423748

RESUMEN

Mammalian sperm flagellum contains the midpiece characterized by a mitochondrial sheath that packs tightly around the axoneme and outer dense fibers. Mitochondria are known as the "powerhouse" of the cell, and produce ATP through the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS). However, the contribution of the TCA cycle and OXPHOS to sperm motility and male fertility is less clear. Cytochrome c oxidase (COX) is an oligomeric complex localized within the mitochondrial inner membrane, and the terminal enzyme of the mitochondrial electron transport chain in eukaryotes. Both COX6B2 and COX8C are testis-enriched COX subunits whose functions in vivo are poorly studied. Here, we generated Cox6b2 and Cox8c knockout (KO) mice using the CRISPR/Cas9 system. We examined their fertility and sperm mitochondrial function to determine the significance of testis-enriched COX subunits in male fertility. The mating test revealed that disrupting COX6B2 induces male subfertility, while disrupting COX8C does not affect male fertility. Cox6b2 KO spermatozoa showed low sperm motility, but mitochondrial function was normal according to oxygen consumption rates. Therefore, low sperm motility seems to cause subfertility in Cox6b2 KO male mice. These results also indicate that testis-enriched COX, COX6B2 and COX8C, are not essential for OXPHOS in mouse spermatozoa.


Asunto(s)
Infertilidad Masculina , Testículo , Humanos , Masculino , Ratones , Animales , Testículo/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Semen/metabolismo , Motilidad Espermática , Espermatozoides , Fertilidad , Ratones Noqueados , Mamíferos/metabolismo
5.
Nucl Med Commun ; 45(1): 45-50, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37901921

RESUMEN

OBJECTIVE: To estimate the gonadal doses irradiated from urine- contaminated diapers during diuretic renal scintigraphy. METHODS: Images of 31 patients (18 males and 13 females) with urine-contaminated diapers during 99m Tc-MAG3 renal scintigraphy were analyzed. The count rate of the diapers was converted into a time-activity curve based on the calibrated factor of the gamma camera system. The cumulative activity was determined from the area under the curve. By incorporating dose per unit cumulative activity pre-calculated from Monte Carlo simulation with 0-year phantom, the gonadal dose irradiated from diaper was calculated. To assess the degree of this additionally introduced dose from diapers, the calculated gonadal dose was compared to the internal gonadal dose from injected radiotracer activity. RESULTS: The cumulative activities irradiated from urine-contaminated diapers were 1.12 E04 ±â€…1.29E04 MBq.s in male infants, which was nearly half of the 1.94 E04 ±â€…1.80E04 MBq.s ( P  = 0.15) in female infants. However, the absorbed doses for testes in male infants were 7.37E-01 ±â€…8.50E-01 mGy, which was approximately 10 times the 6.38E-02 ±â€…5.94E-02 mGy for ovaries in female infants ( P  < 0.01). The diaper-introduced dose for testes and ovaries was 91.7% and 3.9% of the gonadal doses from the injected activity in patients with normal renal function, and 99.0% and 4.3% of those in patients with abnormal renal function. CONCLUSION: Urine-contaminated diapers introduced additional radiation doses to infant patients during 99m Tc-MAG3 renal scintigraphy. The gonadal doses were of significance in male infants who had nearly double the absorbed dose for the testes.


Asunto(s)
Diuréticos , Cuidado del Lactante , Lactante , Niño , Humanos , Masculino , Femenino , Tecnecio Tc 99m Mertiatida , Cintigrafía
6.
Aging (Albany NY) ; 15(23): 14323-14332, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38095642

RESUMEN

OBJECTIVE: To investigate the effect of Notch-1 signaling on NAFLD and its molecular mechanism. METHODS: The lipid deposition in liver tissues was detected by oil red O staining. Western blotting was performed to detect the expressions of SREBP1C, SREBP2, LXR, IL-1ß, IL-18, NLRP3, Notch-1, NOX2, NOX4, p-PI3K and p-SHP2 in macrophages, and the expressions of ALIX, CD9, IL-1ß and SREBP1C in exosomes. Macrophages in the Notch-1MAC-KO group and Notch-1WT group were treated with FFA, and those in the Notch-1WT+FFA group and Notch-1MAC-KO+FFA group were treated with SHP2 inhibitors PHPS1 and Relaxin. RESULTS: It was observed by oil red O staining that lipid deposition in mice with NAFLD was reduced in the Notch-1MAC-KO group. The results of Western blotting showed that the expressions of ALIX, CD9, IL-1ß and SREBP1C in macrophage exosomes were significantly lower in the Notch-1MAC-KO group than in the Notch-1WT group. In macrophages, the expressions of SREBP1C, SREBP2, LXR, IL-1ß, IL-18, Notch-1, NOX2, NOX4 and p-PI3K significantly decreased, while the expression of p-SHP2 significantly increased in the Notch-1MAC-KO group compared with the Notch-1WT group. The Notch-1MAC-KO+FFA group had significantly decreased expressions of SREBP1C, NLRP3, IL-1ß, IL-18, SREBP2, NOX2, NOX4 and p-PI3K and a significantly increased expression of p-SHP2 compared with the Notch-1WT+FFA group. However, the differences in the above proteins were all eliminated after PHPS1 and Relaxin were added. CONCLUSION: Specific knockout of Notch-1 attenuates NAFLD, and reduces inflammation and lipid deposition in the liver by promoting SHP2 phosphorylation.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Relaxina , Animales , Ratones , Interleucina-18/metabolismo , Lípidos , Hígado/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Relaxina/metabolismo
7.
Andrology ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38084666

RESUMEN

BACKGROUND: Mammalian fertilization is mediated by multiple sperm acrosomal proteins, many of which are testis-enriched transmembrane glycoproteins expressed during spermiogenesis (e.g., Izumo sperm-egg fusion 1, Sperm acrosome associated 6, and Transmembrane protein 95). METHODS: We hypothesized that proteins with these features might have a role in sperm-egg interaction and thus carried out an in-silico screen based on multiple public databases. We generated knockout mouse lines lacking seven candidate proteins by the CRISPR/Cas9 system and conducted detailed analyses on the fecundity of the knockout males, as well as their testis appearance and weight, testis and epididymis histology, and sperm motility and morphology. RESULTS: Through the in-silico screen, we identified 4932438H23Rik, A disintegrin and metalloproteinase domain-containing protein 29, SAYSvFN domain-containing protein 1, Sel-1 suppressor of lin-12-like 2 (C. elegans), Testis-expressed protein 2, Transmembrane and immunoglobulin domain-containing 3, and Zinc and ring finger 4. Phenotypic analyses unveiled that the knockout males showed normal testis gross appearance, normal testis and epididymis histology, and normal sperm morphology and motility. Fertility tests further indicated that the knockout male mice could sire pups with normal litter sizes when paired with wild-type females. DISCUSSION AND CONCLUSION: These findings suggest that these seven proteins are individually dispensable for male reproduction and fertilization. Future studies are warranted to devise advanced in-silico screening approaches that permit effective identification of gamete fusion-required sperm proteins.

8.
Aging (Albany NY) ; 15(23): 13655-13668, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38048186

RESUMEN

In order to detect the effect of EZH2 genes on proliferation, migration, invasion, and apoptosis of colon carcinoma cell strains HCT116 and HT29 by the Wnt/ß-catenin signaling pathway, qRT-PCR was applied to measure relative expressions of EZH2, RUNX3, CEA, CA199, MMP-9, VEGF, ß-catenin, and CyclinD1 in each group; Western-blot was employed with the intention of exploring relative expressions of these proteins in vivo and in vitro; monoclonal proliferation experiments and CCK-8 assay was adopted so as to check cell proliferation; the effect on cell migration was investigated via Transwell assay and cell scratch wound assay; flow cytometry was applied with a view to determining the effect on cell apoptosis. Transfected HCT116 cells are injected subcutaneously into nude mice. In colon cell strains HCT-116 and HT29, contrasted to the si-NC group, the RUNX3 expression was prominently up-regulated in the si-EZH2 group. Besides, expressions of CEA, CA199, MMP-9, and VEGF were significantly reduced; down-regulation of EZH2 genes remarkably inhibited cell proliferation, invasion and migration when facilitating apoptosis; down-regulation of EZH2 genes also significantly reduced expressions of essential proteins ß-catenin and CyclinD1 on the Wnt pathway. The subcutaneous tumor body of nude mice was reduced. EZH2-OE is the opposite trend to si-EZH2; The EZH2 gene may target regulatory RUNX3 regulation via that Wnt/ß-catenin signaling pathway, hence affecting colon carcinoma cell proliferation, invasion, migration, and apoptosis. Therefore, EZH2 may become a promising target for the clinical therapy of colon carcinoma.


Asunto(s)
Carcinoma , Neoplasias del Colon , MicroARNs , Animales , Humanos , Ratones , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Regulación hacia Abajo , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Desnudos , MicroARNs/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Vía de Señalización Wnt/genética
9.
Aging (Albany NY) ; 15(24): 15196-15212, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38149979

RESUMEN

OBJECTIVE: Notch-1 signaling is significantly associated with the occurrence and development of atherosclerosis (AS). However, the molecular mechanisms underlying the specific deletion of Notch-1 in AS-associated macrophages are not fully understood. This study aimed to investigate the effects of Notch-1 in AS. METHODS AND RESULTS: Tissue samples were obtained from atherosclerotic segments of human carotid arteries. Immunofluorescence staining showed that Notch-1 was significantly colocalized with macrophages (CD68+), and Notch-1 staining was increased in human vulnerable plaques. Notch-1MAC-KO/ApoE-/- mice were generated in which Notch-1 was selectively inactivated in macrophages, and WT for littermate control mice (ApoE-/-/Notch-1WT). A control group was then established. All mice fed with a high-fat and Oil Red O, Movat, a-SMA, CD68, and Sirius red staining were used to evaluate the morphology. Specific deletion of Notch-1 in macrophages repressed the pathophysiology of AS. Immunofluorescent staining and Western blotting revealed that Notch-1MAC-KO repressed M1 and M2 responses in AS. Here, GSEA revealed that Notch-1 activation and PI3K signaling were statistically significantly correlated with each other, and Notch-1 was involved in the regulation of the PI3K signaling pathway. In the in vitro experiments, the secretion of Arg-1 and exosomes was classified by peritoneal macrophages of Notch-1MAC-KO/ApoE-/- and Notch-1WT/ApoE-/- mice. Immunohistochemistry staining and Western blotting were used to measure the expression levels of Notch1, PI3K, p-PI3K, AKT, p-AKT, Arg-1, IL-6, CD36, SREBP-1, CD206, iNOS, cleaved-caspase-3/-9, Bax, CD9, Alix and TSG101 in the peritoneal macrophages and exosomes, respectively. CONCLUSIONS: The specific deletion of Notch-1 in macrophage represses the formation and development of AS via the PI3K/AKT signaling pathway.


Asunto(s)
Aterosclerosis , Macrófagos , Receptor Notch1 , Animales , Humanos , Ratones , Antiinflamatorios/farmacología , Apolipoproteínas E/metabolismo , Aterosclerosis/genética , Aterosclerosis/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Estrés Oxidativo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor Notch1/metabolismo
12.
Oncol Res ; 31(2): 125-139, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37304233

RESUMEN

This research aimed to explore the influence of Src homology-2 containing protein tyrosine phosphatase (SHP-2) on the functions of tyrosine kinase receptors with immunoglobulin and EGF homology domains 2 (Tie2)-expressing monocyte/macrophages (TEMs) and the influence of the angiopoietin(Ang)/Tie2-phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) (Ang/Tie2-PI3K/Akt/mTOR) signaling pathway on the tumor microvascular remodeling in an immunosuppressive microenvironment. In vivo, SHP-2-deficient mice were used to construct colorectal cancer (CRC) liver metastasis models. SHP-2-deficient mice had significantly more metastatic cancer and inhibited nodules on the liver surface than wild-type mice, and the high-level expression of p-Tie2 was found in the liver tissue of the macrophages' specific SHP-2-deficient mice (SHP-2MAC-KO) + planted tumor mice. Compared with the SHP-2 wild type mice (SHP-2WT) + planted tumor group, the SHP-2MAC-KO + planted tumor group experienced increased expression of p-Tie2, p-PI3K, p-Akt, p-mTOR, vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), matrix metalloproteinase 2 (MMP2), and MMP9 in the liver tissue. TEMs selected by in vitro experiments were co-cultured with remodeling endothelial cells and tumor cells as carriers. It was found that when Angpt1/2 was used for stimulation, the SHP-2MAC-KO + Angpt1/2 group displayed evident increases in the expression of the Ang/Tie2-PI3K/Akt/mTOR pathway. The number of cells passing through the lower chamber and the basement membrane and the number of blood vessels formed by cells compared with the SHP-2WT + Angpt1/2 group, while these indexes were subjected to no changes under the simultaneous stimulation of Angpt1/2 + Neamine. To sum up, the conditional knockout of SHP-2 can activate the Ang/Tie2-PI3K/Akt/mTOR pathway in TEMs, thereby strengthening tumor micro angiogenesis in the microenvironment and facilitating CRC liver metastasis.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Animales , Humanos , Ratones , Neoplasias Colorrectales/genética , Células Endoteliales , Neoplasias Hepáticas/genética , Metaloproteinasa 2 de la Matriz , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Serina-Treonina Quinasas TOR , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Receptor TIE-2
13.
Int J Mol Sci ; 24(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37176089

RESUMEN

Heterogeneous three-dimensional (3D) reconstruction in single-particle cryo-electron microscopy (cryo-EM) is an important but very challenging technique for recovering the conformational heterogeneity of flexible biological macromolecules such as proteins in different functional states. Heterogeneous projection image classification is a feasible solution to solve the structural heterogeneity problem in single-particle cryo-EM. The majority of heterogeneous projection image classification methods are developed using supervised learning technology or require a large amount of a priori knowledge, such as the orientations or common lines of the projection images, which leads to certain limitations in their practical applications. In this paper, an unsupervised heterogeneous cryo-EM projection image classification algorithm based on autoencoders is proposed, which only needs to know the number of heterogeneous 3D structures in the dataset and does not require any labeling information of the projection images or other a priori knowledge. A simple autoencoder with multi-layer perceptrons trained in iterative mode and a complex autoencoder with residual networks trained in one-pass learning mode are implemented to convert heterogeneous projection images into latent variables. The extracted high-dimensional features are reduced to two dimensions using the uniform manifold approximation and projection dimensionality reduction algorithm, and then clustered using the spectral clustering algorithm. The proposed algorithm is applied to two heterogeneous cryo-EM datasets for heterogeneous 3D reconstruction. Experimental results show that the proposed algorithm can effectively extract category features of heterogeneous projection images and achieve high classification and reconstruction accuracy, indicating that the proposed algorithm is effective for heterogeneous 3D reconstruction in single-particle cryo-EM.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Microscopía por Crioelectrón/métodos , Análisis por Conglomerados , Imagen Individual de Molécula , Procesamiento de Imagen Asistido por Computador/métodos
14.
Phys Imaging Radiat Oncol ; 26: 100430, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36970447

RESUMEN

Background and purpose: Free breathing (FB) positron emission tomography (PET) images are routinely used in radiotherapy for lung cancer patients. Respiration-induced artifacts in these images compromise treatment response assessment and obstruct clinical implementation of dose painting and PET-guided radiotherapy. The purpose of this study is to develop a blurry image decomposition (BID) method to correct motion-induced image-reconstruction errors in FB-PETs. Materials and methods: Assuming a blurry PET is represented as an average of multi-phase PETs. A four-dimensional computed-tomography image is deformably registered from the end-inhalation (EI) phase to other phases. With the registration-derived deformation maps, PETs at other phases can be deformed from a PET at the EI phase. To reconstruct the EI-PET, the difference between the blurry PET and the average of the deformed EI-PETs is minimized using a maximum-likelihood expectation-maximization algorithm. The developed method was evaluated with computational and physical phantoms as well as PET/CT images acquired from three patients. Results: The BID method increased the signal-to-noise ratio from 1.88 ± 1.05 to 10.5 ± 3.3 and universal-quality index from 0.72 ± 0.11 to 1.0 for the computational phantoms, and reduced the motion-induced error from 69.9% to 10.9% in the maximum of activity concentration and from 317.5% to 8.7% in the full width at half maximum of the physical PET-phantom. The BID-based corrections increased the maximum standardized-uptake values by 17.7 ± 15.4% and reduced tumor volumes by 12.5 ± 10.4% on average for the three patients. Conclusions: The proposed image-decomposition method reduces respiration-induced errors in PET images and holds potential to improve the quality of radiotherapy for thoracic and abdominal cancer patients.

15.
Proc Natl Acad Sci U S A ; 120(8): e2207263120, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36787362

RESUMEN

Sperm acrosomal membrane proteins, such as Izumo sperm-egg fusion 1 (IZUMO1) and sperm acrosome-associated 6 (SPACA6), play essential roles in mammalian gamete binding or fusion. How their biosynthesis is regulated during spermiogenesis has largely remained elusive. Here, we show that 1700029I15Rik knockout male mice are severely subfertile and their spermatozoa do not fuse with eggs. 1700029I15Rik is a type-II transmembrane protein expressed in early round spermatids but not in mature spermatozoa. It interacts with proteins involved in N-linked glycosylation, disulfide isomerization, and endoplasmic reticulum (ER)-Golgi trafficking, suggesting a potential role in nascent protein processing. The ablation of 1700029I15Rik destabilizes non-catalytic subunits of the oligosaccharyltransferase (OST) complex that are pivotal for N-glycosylation. The knockout testes exhibit normal expression of sperm plasma membrane proteins, but decreased abundance of multiple acrosomal membrane proteins involved in fertilization. The knockout sperm show upregulated chaperones related to ER-associated degradation (ERAD) and elevated protein ubiquitination; strikingly, SPACA6 becomes undetectable. Our results support for a specific, 1700029I15Rik-mediated pathway underpinning the biosynthesis of acrosomal membrane proteins during spermiogenesis.


Asunto(s)
Acrosoma , Proteínas de la Membrana , Animales , Masculino , Ratones , Acrosoma/metabolismo , Mamíferos/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Noqueados , Semen/metabolismo , Proteínas de Plasma Seminal/metabolismo , Interacciones Espermatozoide-Óvulo , Espermatozoides/metabolismo , Óvulo/metabolismo
16.
Andrology ; 11(4): 698-709, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36698249

RESUMEN

BACKGROUND: Adenosine deaminase domain containing 2 (ADAD2) is a testis-specific protein composed of a double-stranded RNA binding domain and a non-catalytic adenosine deaminase domain. A recent study showed that ADAD2 is indispensable for the male reproduction in mice. However, the detailed functions of ADAD2 remain elusive. OBJECTIVES: This study aimed to investigate the cause of male sterility in Adad2 mutant mice and to understand the molecular functions of ADAD2. MATERIALS AND METHODS: Adad2 homozygous mutant mouse lines, Adad2-/- and Adad2Δ/Δ , were generated by CRISPR/Cas9. Western blotting and immunohistochemistry were used to reveal the expression and subcellular localization of ADAD2. Co-immunoprecipitation tandem mass spectrometry was employed to determine the ADAD2-interacting proteins in mouse testes. RNA-sequencing analyses were carried out to analyze the transcriptome and PIWI-interacting RNA (piRNA) populations in wildtype and Adad2 mutant testes. RESULTS: Adad2-/- and Adad2Δ/Δ mice exhibit male-specific sterility because of abnormal spermiogenesis. ADAD2 interacts with multiple RNA-binding proteins involved in piRNA biogenesis, including MILI, MIWI, RNF17, and YTHDC2. ADAD2 co-localizes and forms novel granules with RNF17 in spermatocytes. Ablation of ADAD2 impairs the formation of RNF17 granules, decreases the number of cluster-derived pachytene piRNAs, and increases expression of ping-pong-derived piRNAs. DISCUSSION AND CONCLUSION: In collaboration with RNF17 and other RNA-binding proteins in spermatocytes, ADAD2 directly or indirectly functions in piRNA biogenesis.


Asunto(s)
Adenosina Desaminasa , ARN de Interacción con Piwi , Animales , Masculino , Ratones , ARN Interferente Pequeño/genética , Adenosina Desaminasa/metabolismo , Espermatogénesis/genética , Testículo/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
17.
J Cell Sci ; 135(22)2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36416181

RESUMEN

In sexually reproducing organisms, the genetic information is transmitted from one generation to the next via the merger of male and female gametes. Gamete fusion is a two-step process involving membrane recognition and apposition through ligand-receptor interactions and lipid mixing mediated by fusion proteins. HAP2 (also known as GCS1) is a bona fide gamete fusogen in flowering plants and protists. In vertebrates, a multitude of surface proteins have been demonstrated to be pivotal for sperm-egg fusion, yet none of them exhibit typical fusogenic features. In this Cell Science at a Glance article and the accompanying poster, we summarize recent advances in the mechanistic understanding of gamete fusion in eukaryotes, with a particular focus on mammalian species.


Asunto(s)
Eucariontes , Semen , Masculino , Animales , Células Eucariotas , Células Germinativas , Fertilización , Mamíferos
18.
Oxid Med Cell Longev ; 2022: 5719974, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225174

RESUMEN

Objective: To explore the mechanisms of TLR9 from macrophages on mitochondrial apoptosis in cardiomyocytes at early stage of sepsis. Methods: The in vivo and in vitro sepsis mice were bone marrow transplantation (BMT) with wild type (WT) or (toll-like receptor 9) TLR9 knockout (-/- or KO) myeloid cells and then constructed by cecum ligation and puncture (CLP) as vivo experiment and cardiomyocytes cocultured with WT or TLR9-deficient macrophages treated with LPS as vitro experiment, respectively. Sepsis model were performed by CLP. The expression levels of exosome, PI3K/AKT, and ERK1/2, inflammatory factors, and apoptotic proteins were tested by western blot in vivo. Besides, associated apoptotic proteins and JC-1 fluorescence assay were tested in vitro. Results: The expressions of p-PI3K, p-AKT, exosome markers (CD9, CD63, and TSG101), p-ERK1/2, TNF-α, IFN-γ, IL-1ß, and cleaved-caspase-3/-9 were significantly increased in septic mice vs. control mice, and these proteins were declined dramatically in TLR9-/- BMT mice vs. WT BMT mice in sepsis mice models. Meanwhile, the protein expression of cytochrome C, cleaved-caspase-3, and cleaved-caspase-9 increased significantly in primary mouse myocardial cells cocultured with TLR9-/- or WT macrophages stimulated with LPS, and these mitochondrial apoptotic proteins as well as the green 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolcarbocyanine iodide (JC-1) fluorescence were dramatically lower in LPS-stimulated cardiomyocytes cocultured with TLR9-/- than with WT macrophages. Conclusion: TLR9-/- in macrophages suppressed the inflammatory reaction as well as the exosome secretion and resulted in the inhibition of apoptosis and oxidative stress in sepsis-induced cardiomyopathy.


Asunto(s)
Exosomas , Sepsis , Animales , Apoptosis , Bencimidazoles , Carbocianinas , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Citocromos c/metabolismo , Exosomas/metabolismo , Yoduros , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Miocitos Cardíacos/metabolismo , Estrés Oxidativo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sepsis/metabolismo , Receptor Toll-Like 9/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
19.
Proc Natl Acad Sci U S A ; 119(40): e2207805119, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36161911

RESUMEN

Tmem95 encodes a sperm acrosomal membrane protein, whose knockout has a male-specific sterility phenotype in mice. Tmem95 knockout murine sperm can bind to, but do not fuse with, eggs. How TMEM95 plays a role in membrane fusion of sperm and eggs has remained elusive. Here, we utilize a sperm penetration assay as a model system to investigate the function of human TMEM95. We show that human TMEM95 binds to hamster egg membranes, providing evidence for a TMEM95 receptor on eggs. Using X-ray crystallography, we reveal an evolutionarily conserved, positively charged region of TMEM95 as a putative receptor-binding surface. Amino acid substitutions within this region of TMEM95 ablate egg-binding activity. We identify monoclonal antibodies against TMEM95 that reduce the number of human sperm fused with hamster eggs in sperm penetration assays. Strikingly, these antibodies do not block binding of sperm to eggs. Taken together, these results provide strong evidence for a specific, receptor-mediated interaction of sperm TMEM95 with eggs and suggest that this interaction may have a role in facilitating membrane fusion during fertilization.


Asunto(s)
Infertilidad Masculina , Fusión de Membrana , Proteínas de la Membrana , Óvulo , Proteínas de Plasma Seminal , Interacciones Espermatozoide-Óvulo , Espermatozoides , Sustitución de Aminoácidos , Animales , Anticuerpos Monoclonales , Cricetinae , Humanos , Infertilidad Masculina/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Óvulo/metabolismo , Semen/metabolismo , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo , Espermatozoides/metabolismo
20.
Front Genet ; 13: 817118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35601500

RESUMEN

Background: Recent studies highlight the carcinogenesis role of SHC-adaptor protein 1 (SHC1) in cancer initiation, development, and progression. However, its aberrant expression, diagnostic and prognostic value remain unknown in a variety of tumors. Methods: The SHC1 expression profiles were analyzed using GTEx database, TCGA database, Oncomine and CPTAC database. The survival analysis was conducted using GEPIA2, Kaplan-Meier Plotter, UALCAN, and PrognoScan. The diagnostic values of SHC1 were calculated with the "pROC" package in R software. The genetic alteration of SHC1 and mutations were analyzed using cBioPortal. TIMER2 was employed to estimate the correlations between SHC1 expression and tumor-infiltrating immune cells in the TCGA cohort. Enrichment analysis of SHC1 was conducted using the R package "clusterProfiler." Results: SHC1 was ubiquitously highly expressed and closely associated with worse prognosis of multiple major cancer types (all p < 0.05). Further, SHC1 gene mutations were strongly linked to poor OS and DFS in SKCM (all p < 0.05). An enhanced phosphorylation level of SHC1 at the S139 site was observed in clear cell RCC. Additionally, the results revealed SHC1 expression was strongly linked to TMB, MMRs, MSI, TAMs, DNA methylation, m6A RNA methylation, tumor-associated immune infiltration, and immune checkpoints in multiple cancers (all p < 0.05). In addition, the results of the ROC analysis indicated the SHC1 exhibited strong diagnostic capability for KICH (AUC = 0.92), LIHC (AUC = 0.95), and PAAD (AUC = 0.95). Finally, enrichment analysis indicated that SHC1 may potentially involve in the regulation of numerous signaling pathways in cancer metabolism and protein phosphorylation-related functions. Conclusions: These findings highlight that SHC1 plays an important role in the tumor immune microenvironment, and SHC1 has been identified to have prognostic and diagnostic value in multiple cancers. Thus, SHC1 is a potential target for cancer immunotherapy and effective prognostic and diagnostic biomarker.

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