Expression of targets of the RNA-binding protein AUF-1 in human airway epithelium indicates its role in cellular senescence and inflammation

Frontiers in Immunology

Immunology

Alen Faiz¹  Sobia Idrees¹  Matt D. Johansen¹  Philip M. Hansbro²  Thomas Stiff³  Leandro Castellano³  Paola Dama³  Federico Caicci⁴  Annunziata Nigro⁵  Domenico Memoli⁵  Giorgio Giurato⁵  Monica Vitale⁵  Erwin Pavel Lamparelli⁵  Alessandro Vatrella⁵  Jessica Dal Col⁵  Assunta Sellitto⁵  Cristiana Stellato⁵  Maria Assunta Crescenzi⁵  Luca Ricciardi⁶  Ilaria Salvato⁶  Paola Brun⁷  Peter A. Wark⁸  Ian M. Adcock⁹  Francesco Nucera^1,10  Gaetano Caramori^1,10 

[1] Centre for Inflammation, Centenary Institute and University of Technology Sydney, Faculty of Science, School of Life Sciences, Sydney, NSW, Australia;Centre for Inflammation, Centenary Institute and University of Technology Sydney, Faculty of Science, School of Life Sciences, Sydney, NSW, Australia;Immune Health, Hunter Medical Research Institute and The University of Newcastle, Newcastle, NSW, Australia;Department of Biochemistry and Biomedicine, School of Life Sciences, University of Sussex, Brighton, United Kingdom;Department of Biology, University of Padua, Padua, Italy;Department of Medicine, Surgery and Dentistry ‘Scuola Medica Salernitana’, University of Salerno, Salerno, Italy;Department of Medicine, Surgery and Dentistry ‘Scuola Medica Salernitana’, University of Salerno, Salerno, Italy;Respiratory Medicine Unit, Department of Biomedical Sciences, Dentistry and Morphological and Functional Imaging (BIOMORF), University of Messina, Messina, Italy;Department of Molecular Medicine, University of Padua, Padua, Italy;Immune Health, Hunter Medical Research Institute and The University of Newcastle, Newcastle, NSW, Australia;National Heart and Lung Institute, Imperial College London and the National Institute for Health and Care Research (NIHR) Imperial Biomedical Research Centre, London, United Kingdom;Respiratory Medicine Unit, Department of Biomedical Sciences, Dentistry and Morphological and Functional Imaging (BIOMORF), University of Messina, Messina, Italy;

关键词: airway epithelium;    AU-rich element factor 1 (AUF-1);    cell senescence;    chronic inflammation;    chronic obstructive pulmonary disease;    inflammaging;    oxidative stress;    RNA-binding proteins;   

DOI  :  10.3389/fimmu.2023.1192028

 received in 2023-03-22, accepted in 2023-06-06,  发布年份 2023

来源: Frontiers

【 摘 要 】

IntroductionThe RNA-binding protein AU-rich-element factor-1 (AUF-1) participates to posttranscriptional regulation of genes involved in inflammation and cellular senescence, two pathogenic mechanisms of chronic obstructive pulmonary disease (COPD). Decreased AUF-1 expression was described in bronchiolar epithelium of COPD patients versus controls and in vitro cytokine- and cigarette smoke-challenged human airway epithelial cells, prompting the identification of epithelial AUF-1-targeted transcripts and function, and investigation on the mechanism of its loss.ResultsRNA immunoprecipitation-sequencing (RIP-Seq) identified, in the human airway epithelial cell line BEAS-2B, 494 AUF-1-bound mRNAs enriched in their 3’-untranslated regions for a Guanine-Cytosine (GC)-rich binding motif. AUF-1 association with selected transcripts and with a synthetic GC-rich motif were validated by biotin pulldown. AUF-1-targets’ steady-state levels were equally affected by partial or near-total AUF-1 loss induced by cytomix (TNFα/IL1β/IFNγ/10 nM each) and siRNA, respectively, with differential transcript decay rates. Cytomix-mediated decrease in AUF-1 levels in BEAS-2B and primary human small-airways epithelium (HSAEC) was replicated by treatment with the senescence- inducer compound etoposide and associated with readouts of cell-cycle arrest, increase in lysosomal damage and senescence-associated secretory phenotype (SASP) factors, and with AUF-1 transfer in extracellular vesicles, detected by transmission electron microscopy and immunoblotting. Extensive in-silico and genome ontology analysis found, consistent with AUF-1 functions, enriched RIP-Seq-derived AUF-1-targets in COPD-related pathways involved in inflammation, senescence, gene regulation and also in the public SASP proteome atlas; AUF-1 target signature was also significantly represented in multiple transcriptomic COPD databases generated from primary HSAEC, from lung tissue and from single-cell RNA-sequencing, displaying a predominant downregulation of expression.DiscussionLoss of intracellular AUF-1 may alter posttranscriptional regulation of targets particularly relevant for protection of genomic integrity and gene regulation, thus concurring to airway epithelial inflammatory responses related to oxidative stress and accelerated aging. Exosomal-associated AUF-1 may in turn preserve bound RNA targets and sustain their function, participating to spreading of inflammation and senescence to neighbouring cells.

【 授权许可】

Unknown   
Copyright © 2023 Salvato, Ricciardi, Dal Col, Nigro, Giurato, Memoli, Sellitto, Lamparelli, Crescenzi, Vitale, Vatrella, Nucera, Brun, Caicci, Dama, Stiff, Castellano, Idrees, Johansen, Faiz, Wark, Hansbro, Adcock, Caramori and Stellato