Publications by authors named "Jun Tao Zhang"

Aim: To investigate the proliferation regulatory effect of cone-rod homeobox (CRX) in retinal pigment epithelium (RPE) and retinoblastoma (RB) cells to explore the potential application and side effect (oncogenic potential) of CRX-based gene therapy in RPE-based retinopathies.

Methods: Adult human retinal pigment epithelial (ARPE)-19 and human retinal pigment epithelial (RPE)-1 cells and Y79 RB cell were used in the study. Genetic manipulation was performed by lentivirus-based technology.

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Eukaryotic Argonaute proteins (eAgos) utilize short nucleic acid guides to target complementary sequences for RNA silencing, while prokaryotic Agos (pAgos) provide immunity against invading plasmids or bacteriophages. The Sir2-domain associated short pAgo (SPARSA) immune system defends against invaders by depleting NAD and triggering cell death. However, the molecular mechanism underlying SPARSA activation remains unknown.

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  • Scientists studied a special protein called DSR2 found in bacteria that helps defend against viruses called phages.
  • They looked at different forms of DSR2 to understand how it works, especially when it interacts with other proteins and a molecule called NAD.
  • The research found that DSR2 can change shape and that a protein called DSAD1 can block its activity, which helps bacteria protect themselves from phages.
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Argonaute proteins (Agos), which use small RNAs or DNAs as guides to recognize complementary nucleic acid targets, mediate RNA silencing in eukaryotes. In prokaryotes, Agos are involved in immunity: the short prokaryotic Ago/TIR-APAZ (SPARTA) immune system triggers cell death by degrading NAD in response to invading plasmids, but its molecular mechanisms remain unknown. Here we used cryo-electron microscopy to determine the structures of inactive monomeric and active tetrameric Crenotalea thermophila SPARTA complexes, revealing mechanisms underlying SPARTA assembly, RNA-guided recognition of target single-stranded DNA (ssDNA) and subsequent SPARTA tetramerization, as well as tetramerization-dependent NADase activation.

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  • A meta-analysis was conducted to investigate the link between sleep-disordered breathing (SDB) and retinal vein occlusion (RVO), finding a significant association.
  • The analysis included seven studies with over 36,000 adults, where 17.6% had SDB, confirming that individuals with SDB have an almost doubled risk of developing RVO.
  • Subgroup analyses showed consistent results across different types and severities of SDB, reinforcing the connection between SDB and RVO even when accounting for other health factors.
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Sinomenine (SIN), the alkaloid monomer extracted from , is a kind of non-steroidal anti-inflammatory drug widely used in China to treat rheumatoid arthritis (RA) and various glomerular diseases. It has various pharmacological effects such as anti-inflammatory, analgesic, and anti-tumor. As a strong histamine-releasing agent, SIN has drawn increasing attention in regards to its side effects such as allergic, gastrointestinal, and circulatory systemic reactions.

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Type IV CRISPR-Cas systems, which are primarily found on plasmids and exhibit a strong plasmid-targeting preference, are the only one of the six known CRISPR-Cas types for which the mechanistic details of their function remain unknown. Here, we provide high-resolution functional snapshots of type IV-A Csf complexes before and after target dsDNA binding, either in the absence or presence of CasDinG, revealing the mechanisms underlying Csf complex assembly, "DWN" PAM-dependent dsDNA targeting, R-loop formation, and CasDinG recruitment. Furthermore, we establish that CasDinG, a signature DinG family helicase, harbors ssDNA-stimulated ATPase activity and ATP-dependent 5'-3' DNA helicase activity.

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Background: FAT atypical cadherin 1 () acts as a tumor suppressor or oncogene, which regulates cell adherence, proliferation, motility, and actin kinetics. gene expression is closely related to hepatocarcinogenesis; however, the function and mechanism of in hepatocellular carcinoma (HCC) remain unclear.

Methods: Here, we screened for the , which is intimately linked to the development and progression of HCC, both in circulating tumor cells (CTCs) and tumor tissues using next generation sequencing (NGS).

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Background: Hematogenous metastasis is essential for the progression of advanced hepatocellular carcinoma (HCC) and can occur even after patients receive multidisciplinary therapies, including immunotherapy and hepatectomy; circulating tumor cells (CTCs) are one of the dominant components of the metastatic cascade. However, the CTC capture efficiency for HCC is low due to the low sensitivity of the detection method. In this study, epithelial cell adhesion molecule (EpCAM)/vimentin/Glypican-3 (GPC3) antibody-modified lipid magnetic spheres (LMS) were used to capture tumor cells with epithelial phenotype, mesenchymal phenotype and GPC3 phenotype, respectively, in order to capture more CTCs with a more comprehensive phenotype for monitoring tumor metastasis.

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The myophage possesses a contractile tail that penetrates its host cell envelope. Except for investigations on the bacteriophage T4 with a rather complicated structure, the assembly pattern and tail contraction mechanism of myophage remain largely unknown. Here, we present the fine structure of a freshwater cyanophage Pam3, which has an icosahedral capsid of ~680 Å in diameter, connected via a three-section neck to an 840-Å-long contractile tail, ending with a three-module baseplate composed of only six protein components.

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Background: Exosomal proteins from cancer cells are becoming new biomarkers for cancer monitoring and efficacy evaluation. However, their biological function and molecular mechanism underlying tumor metastasis are largely unknown.

Methods: Bioinformatic methods such as bulk gene expression analysis, single-cell RNA sequencing data analysis, and gene set enrichment analysis were employed to identify metastasis-associated proteins.

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The RNA-targeting type III-E CRISPR-gRAMP effector interacts with a caspase-like protease TPR-CHAT to form the CRISPR-guided caspase complex (Craspase), but their functional mechanism is unknown. Here, we report cryo-EM structures of the type III-E gRAMP and gRAMP-TPR-CHAT complexes, before and after either self or non-self RNA target binding, and elucidate the mechanisms underlying RNA-targeting and non-self RNA-induced protease activation. The associated TPR-CHAT adopted a distinct conformation upon self versus non-self RNA target binding, with nucleotides at positions -1 and -2 of the CRISPR-derived RNA (crRNA) serving as a sensor.

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Background: D-amino acid oxidase (DAAO) is a flavoenzyme that specifically catalyzes the deamination of many neutral and basic D-amino acids. This study aims to explore the pathological increment of hippocampal DAAO and its potential relationship with delayed hippocampal neuronal death.

Methods: Ischemia-reperfusion was induced in mice through middle cerebral artery occlusion (MCAO).

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Omega-3 polyunsaturated fatty acids (PUFAs) can play important roles in maintaining mental health and resistance to stress, and omega-3 PUFAs supplementation can display beneficial effects on both the prevention and treatment of depressive disorders. Although the underlying mechanisms are still unclear, accumulated evidence indicates that omega-3 PUFAs can exhibit pleiotropic effects on the neural structure and function. Thus, they play fundamental roles in brain activities involved in the mood regulation.

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  • Cyanobacteria are vital for oxygen production and ecosystem health, but their uncontrolled growth due to eutrophication and global warming leads to harmful blooms, which could potentially be controlled by specific viruses called cyanophages.
  • Researchers isolated five different freshwater cyanophages (Pam1-Pam5) that infect the cyanobacterium Pseudanabaena mucicola from a lake in China, revealing unique genetic characteristics and evolutionary distinctions.
  • The study recommends a systematic approach to identify cyanophages using metagenomic data, which could enhance understanding and management of cyanobacterial blooms.
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  • * The researchers developed drug-loaded microspheres (GPC3/EpCAM-LEN-MLs) that showed high drug encapsulation and effective inhibition of HCC cell growth while inducing cell death, evidenced by cytotoxicity tests.
  • * MRI findings indicate that these modified liposomes can effectively track and localize tumor cells, suggesting their potential use for both diagnosing and treating HCC as well as serving as an MRI contrast agent for malignant tumors.
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Despite previous structural analyses of bacteriophages, quite little is known about the structures and assembly patterns of cyanophages. Using cryo-EM combined with crystallography, we solve the near-atomic-resolution structure of a freshwater short-tailed cyanophage, Pam1, which comprises a 400-Å-long tail and an icosahedral capsid of 650 Å in diameter. The outer capsid surface is reinforced by trimeric cement proteins with a β-sandwich fold, which structurally resemble the distal motif of Pam1's tailspike, suggesting its potential role in host recognition.

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A-1(L) is a freshwater cyanophage with a contractile tail that specifically infects sp. PCC 7120, one of the model strains for molecular studies of cyanobacteria. Although isolated for half a century, its structure remains unknown, which limits our understanding on the interplay between A-1(L) and its host.

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Background: Since the initial recognition of coronavirus disease 2019 (COVID-19) in Wuhan, this infectious disease has spread to most areas of the world. The pathogenesis of COVID-19 is yet unclear. Hepatitis B virus (HBV) reactivation occurring in COVID-19 patients has not yet been reported.

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(), a perennial herbaceous legume, is widely distributed in southern China. . has antipyretic, antiseptic and expectorant properties and can therefore be used as a phytomedicine (Ghosal et al.

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Background: Postmenopausal osteoporosis (PMO) that results from estrogen withdrawal is the most common primary osteoporosis among older women. However, little is known about the mechanism of PMO, and effective treatment of PMO is limited.

Methods: We used real-time polymerase chain reaction (qPCR), Western blotting, and RNA pull down to investigate the relationship between miR-186 and MOB Kinase Activator 1A (Mob1).

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Embryonic stem cells (ESCs) derived from somatic cell nuclear transfer (SCNT) and induced pluripotent stem cells (iPSCs) are promising tools for meeting the personalized requirements of regenerative medicine. However, some obstacles need to be overcome before clinical trials can be undertaken. First, donor cells vary, and the reprogramming procedures are diverse, so standardization is a great obstacle regarding SCNT and iPSCs.

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IWe have designed, simulated, and experimentally tested a broadband metamaterial absorber loaded with lumped resistors in the microwave range. Compared with an electric resonator structure absorber, the composite absorber loaded with lumped resistors has stronger absorptivity over an extremely extended bandwidth. The simulated results show that an effective absorption bandwidth covers from 7.

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