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Infections caused by SARS-CoV-2 have brought great harm to human health. After transmission for over two years, SARS-CoV-2 has diverged greatly and formed dozens of different lineages. Understanding the trend of its genome evolution could help foresee difficulties in controlling transmission of the virus. In this study, we conducted an extensive monthly survey and in-depth analysis on variations of nucleotide, amino acid and codon numbers in 311,260 virus samples collected till January 2022. The results demonstrate that the evolution of SARS-CoV-2 is toward increasing U-content and reducing genome-size. C, G and A to U mutations have all contributed to this U-content increase. Mutations of C, G and A at codon position 1, 2 or 3 have no significant difference in most SARS-CoV-2 lineages. Current viruses are more cryptic and more efficient in replication, and are thus less virulent yet more infectious. Delta and Omicron variants have high mutability over other lineages, bringing new threat to human health. This trend of genome evolution may provide a clue for tracing the origin of SARS-CoV-2, because ancestral viruses should have lower U-content and probably bigger genome-size.
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http://dx.doi.org/10.1016/j.ijbiomac.2022.02.034 | DOI Listing |
J Clin Invest
September 2025
Department of Clinical and Biomedical Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom.
Understanding the genetic causes of diseases affecting pancreatic β cells and neurons can give insights into pathways essential for both cell types. Microcephaly, epilepsy and diabetes syndrome (MEDS) is a congenital disorder with two known aetiological genes, IER3IP1 and YIPF5. Both genes encode proteins involved in endoplasmic reticulum (ER) to Golgi trafficking.
View Article and Find Full Text PDFJ Clin Invest
September 2025
Department of Cellular and Molecular Medicine, UCSD, La Jolla, United States of America.
3-O-sulfation of heparan sulfate (HS) is the key determinant for binding and activation of Antithrombin III (AT). This interaction is the basis of heparin treatment to prevent thrombotic events and excess coagulation. Antithrombin-binding HS (HSAT) is expressed in human tissues, but is thought to be expressed in the subendothelial space, mast cells, and follicular fluid.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research, International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug De
Proliferative retinopathy is a leading cause of irreversible blindness in humans; however, the molecular mechanisms behind the immune cell-mediated retinal angiogenesis remain poorly elucidated. Here, using single-cell RNA sequencing in an oxygen-induced retinopathy (OIR) model, we identified an enrichment of sorting nexin (SNX)-related pathways, with SNX3, a member of the SNX family that is involved in endosomal sorting and trafficking, being significantly upregulated in the myeloid cell subpopulations of OIR retinas. Immunostaining showed that SNX3 expression is markedly increased in the retinal microglia/macrophages of mice with OIR, which is mainly located within and around the neovascular tufts.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202.
Retinal ganglion cells (RGCs) are highly compartmentalized neurons whose long axons serve as the sole connection between the eye and the brain. In both injury and disease, RGC degeneration occurs in a similarly compartmentalized manner, with distinct molecular and cellular responses in the axonal and somatodendritic regions. The goal of this study was to establish a microfluidic-based platform to investigate RGC compartmentalization in both health and disease states.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
Centre for Experimental Medicine & Rheumatology, William Harvey Research Institute and Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom.
MS4A4A belongs to the MS4A tetraspan protein superfamily and is selectively expressed by the monocyte-macrophage lineage. In this study, we aimed to evaluate the role of MS4A4A+ macrophages in rheumatoid arthritis (RA) pathogenesis and response to treatment. RNA sequencing and immunohistochemistry of synovial samples from either early treatment-naïve or active chronic RA patients showed that MS4A4A expression positively correlated with synovial inflammation.
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