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CRISPR systems are widespread in the prokaryotic world, providing adaptive immunity against mobile genetic elements. Type III CRISPR systems, with the signature gene cas10, use CRISPR RNA to detect non-self RNA, activating the enzymatic Cas10 subunit to defend the cell against mobile genetic elements either directly, via the integral histidine-aspartate (HD) nuclease domain or indirectly, via synthesis of cyclic oligoadenylate second messengers to activate diverse ancillary effectors. A subset of type III CRISPR systems encode an uncharacterized CorA-family membrane protein and an associated NrN family phosphodiesterase that are predicted to function in antiviral defence. Here we demonstrate that the CorA-associated type III-B (Cmr) CRISPR system from Bacteroides fragilis provides immunity against mobile genetic elements when expressed in Escherichia coli. However, B. fragilis Cmr does not synthesize cyclic oligoadenylate species on activation, instead generating S-adenosyl methionine (SAM)-AMP (SAM is also known as AdoMet) by conjugating ATP to SAM via a phosphodiester bond. Once synthesized, SAM-AMP binds to the CorA effector, presumably leading to cell dormancy or death by disruption of the membrane integrity. SAM-AMP is degraded by CRISPR-associated phosphodiesterases or a SAM-AMP lyase, potentially providing an 'off switch' analogous to cyclic oligoadenylate-specific ring nucleases. SAM-AMP thus represents a new class of second messenger for antiviral signalling, which may function in different roles in diverse cellular contexts.
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http://dx.doi.org/10.1038/s41586-023-06620-5 | DOI Listing |
JB JS Open Access
September 2025
Shriners Children's Philadelphia, Philadelphia, Pennsylvania.
Background: Vertebral body tethering (VBT) offers an alternative treatment for patients with idiopathic scoliosis. We present our finalized Food and Drug Administration Investigational Device Exemption (IDE) study results on VBT.
Methods: We retrospectively reviewed patients with Lenke Type IA/B curves who underwent VBT between 2011 and 2015.
Congenital dyserythropoietic anemia type III (CDA III) is an extremely rare inherited disorder characterized by ineffective erythropoiesis, multinucleated erythroblasts in the bone marrow, and variable clinical gravity. We report the case of a 6-year-old boy, presenting with abdominal distension, failure to thrive, dark urine, intermittent itching, and recurrent infections. Physical examination revealed pallor, hepatomegaly, and splenomegaly.
View Article and Find Full Text PDFClin Kidney J
September 2025
Department of Nephrology. University Clinical Hospital, INCLIVA, Valencia. RICORS Renal Instituto de salud Carlos III, Valencia. Spain.
Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as a major contributor to systemic metabolic dysfunction and is increasingly recognized as a risk enhancer for both cardiovascular disease (CVD) and chronic kidney disease (CKD). This review explores the complex interconnections between MASLD, CVD, and CKD, with emphasis on shared pathophysiological mechanisms and the clinical implications for risk assessment and management. We describe the crosstalk among the liver, heart, and kidneys, focusing on insulin resistance, chronic inflammation, and progressive fibrosis as key mediators.
View Article and Find Full Text PDFBackgroundRAY1216 is an alpha-ketoamide-based peptide inhibitor of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) major protease (M). This study evaluated the absorption, distribution, metabolism and excretion of [C]-labelled RAY1216 by oral administration.Research design and methodsThis phase Ι study was designed to assess the pharmacokinetics, mass balance and metabolic pathways in 6 healthy Chinese adult men after a single fasting oral administration of 240 mL (containing 400 mg/100 μCi) [C] RAY1216.
View Article and Find Full Text PDFZhejiang Da Xue Xue Bao Yi Xue Ban
September 2025
Institute of Brain Science and Disease Research Institute, Qingdao University, Qingdao 266075, Shandong Province, China.
Objectives: To investigate the role of a neural pathway from oxytocin (OXT) neurons in the hypothalamic paraventricular nucleus (PVN) to γ-aminobutyric acid (GABA) neurons in the trigeminal nucleus caudalis (TNC) in regulating pain sensitization in a mouse model of chronic migraine and to explore the underlying mechanisms.
Methods: A chronic migraine model was established by intraperitoneal injection of nitroglycerin (NTG, 10 mg/kg) on days 1, 3, 5, 7, and 9. The study consisted of four parts: PartⅠ: Wild-type C57BL/6J mice were divided into 4 groups (=6 in each), receiving single or repeated injection of NTG or saline, respectively.