The hepatitis B X protein (HBx) plays a role in the epigenetic regulation of hepatitis B virus (HBV) replication. This study investigated the effects of HBx mutations on HBV transcription and the recruitment of HBx, histone acetyl-transferase P300 and histone deacetylase 1 (HDAC1) to circularized HBV DNA (which resembles covalently closed circular DNA [cccDNA]). Compared with wild type, majority of mutants had lower levels of intracellular HBV RNA (44-77% reduction) and secretory HBsAg (25-81% reduction), and 12 mutants had a reduction in intracellular encapsidated HBV DNA (33-64% reduction). Eight mutants with >70% reduction in HBV RNA and/or HBsAg were selected for chromatin immunoprecipitation analysis. Four HBx mutants with mutations in amino acid residues 55-60 and 121-126 had a lower degree of HBx-cccDNA association than wild type HBx (mean % input: 0.02-0.64% vs. 3.08% in wild type). A reduced association between cccDNA and P300 (mean % input: 0.69-1.81% vs. 3.48% in wild type) and an augmented association with HDAC1 (mean % input: 4.01-14.0% vs. 1.53% in wild type) were detected. HBx amino acid residues 55-60 and 121-126 may play an important role in HBV transcription regulation, via their impeded interaction with cccDNA and altered recruitment of histone modifying enzymes to cccDNA.
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http://dx.doi.org/10.1038/s41598-020-57637-z | DOI Listing |
Eur J Nucl Med Mol Imaging
January 2025
Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China.
Purpose: Since fibroblast activation protein (FAP), one predominant biomarker of cancer associated fibroblasts (CAFs), is highly expressed in the tumor stroma of various epidermal-derived cancers, targeting FAP for tumor diagnosis and treatment has shown substantial potentials in both preclinical and clinical studies. However, in preclinical settings, tumor-bearing mice exhibit relatively low absolute FAP expression levels, leading to challenges in acquiring high-quality PET images using radiolabeled FAP ligands (FAPIs) with low molar activity, because of which a saturation effect in imaging is prone to happen. Moreover, how exactly the molar dose of FAPI administered to a mouse influences the targeted PET imaging and radiotherapy remains unclear now.
View Article and Find Full Text PDFGlycoconj J
January 2025
Department of Medical Biotechnology and Translational Medicine, University of Milano, Milan, Italy.
Cystic Fibrosis (CF) is a life-threatening hereditary disease resulting from mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene that encodes a chloride channel essential for ion transport in epithelial cells. Mutations in CFTR, notably the prevalent F508del mutation, impair chloride transport, severely affecting the respiratory system and leading to recurrent infections. Recent therapeutic advancements include CFTR modulators such as ETI, a combination of two correctors (Elexacaftor and Tezacaftor) and a potentiator (Ivacaftor), that can improve CFTR function in patients with the F508del mutation.
View Article and Find Full Text PDFPlant Physiol
January 2025
The State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing Agricultural University, Nanjing 210095, China.
Chromatin remodeling plays a crucial role in controlling gene transcription by modifying chromatin structure. However, the involvement of chromatin remodeling in plant stress responses, especially cold tolerance, through chromatin accessibility remains largely unexplored. Here, we report that rice (Oryza sativa L.
View Article and Find Full Text PDFNucleic Acids Res
January 2025
SynVaccine Ltd, Ramat Hachayal, 3 Golda Meir Street, Science Park, Nes Ziona 7403648, Israel.
Many viruses of the Flaviviridae family, including the Zika virus (ZIKV), are human pathogens of significant public health concerns. Despite extensive research, there are currently no approved vaccines available for ZIKV and specifically no live-attenuated Zika vaccine. In this current study, we suggest a novel computational algorithm for generating live-attenuated vaccines via the introduction of silent mutation into regions that undergo selection for strong or weak local RNA folding or into regions that exhibit medium levels of sequence conservation.
View Article and Find Full Text PDFEpilepsia
January 2025
Division of Pediatric Neurology and Developmental Medicine, Department of Pediatrics, Duke University, Durham, North Carolina, USA.
Objective: This study was undertaken to test the following hypotheses in the Atp1a3 mouse (which carries the most common human ATP1A3 (the major subunit of the neuronal Na/K-adenosine triphosphatase [ATPase]) mutation, D801N): sudden unexpected death in epilepsy (SUDEP) occurs during seizures and is due to terminal apneas in some and due to lethal cardiac arrhythmias in others; and Atp1a3 mice have central cardiorespiratory dysregulation and abnormal respiratory drive.
Methods: Comparison was made of littermate wild-type and Atp1a3 groups using (1) simultaneous in vivo video-telemetry recordings of electroencephalogram, electrocardiogram, and breathing; (2) whole-body plethysmography; and (3) hypoglossal nerve recordings.
Results: In Atp1a3 mice, (1) SUDEP consistently occurred during seizures that were more severe than preterminal seizures; (2) seizure clustering occurred in periods preceding SUDEP; (3) slowing of breathing rate (BR) and heart rate was observed preictally before preterminal and terminal seizures; and (4) the sequence during terminal seizures was as follows: bradypnea with bradycardia/cardiac arrhythmias, then terminal apnea, followed by terminal cardiac arrhythmias.
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