title: Nontemplated nucleotide additions distinguish the small RNA composition in cells from exosomes.
abstract: Functional biomolecules, including small noncoding RNAs (ncRNAs), are released and transmitted between mammalian cells via extracellular vesicles (EVs), including endosome-derived exosomes. The small RNA composition in cells differs from exosomes, but underlying mechanisms have not been established. We generated small RNA profiles by RNA sequencing (RNA-seq) from a panel of human B cells and their secreted exosomes. A comprehensive bioinformatics and statistical analysis revealed nonrandomly distributed subsets of microRNA (miRNA) species between B cells and exosomes. Unexpectedly, 3' end adenylated miRNAs are relatively enriched in cells, whereas 3' end uridylated isoforms appear overrepresented in exosomes, as validated in naturally occurring EVs isolated from human urine samples. Collectively, our findings suggest that posttranscriptional modifications, notably 3' end adenylation and uridylation, exert opposing effects that may contribute, at least in part, to direct ncRNA sorting into EVs.
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands; Exosomes Research Group, VU University Medical Center, 1007MB Amsterdam, the Netherlands. Electronic address: d.koppers@vumc.nl.
authors.forename: Danijela
authors.initials: D
authors.lastname: Koppers-Lalic
authors.affiliation: Department of Genetics, Computational Genomics and Bioinformatics Group, University of Granada, Granada 18071, Spain.
authors.forename: Michael
authors.initials: M
authors.lastname: Hackenberg
authors.affiliation: Department of Urology, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Irene V
authors.initials: IV
authors.lastname: Bijnsdorp
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands; Exosomes Research Group, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Monique A J
authors.initials: MAJ
authors.lastname: van Eijndhoven
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands; Exosomes Research Group, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Payman
authors.initials: P
authors.lastname: Sadek
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Daud
authors.initials: D
authors.lastname: Sie
authors.affiliation: CNR-National Research Council of Italy, IGM, and SC Laboratory of Musculoskeletal Cell Biology, IOR, 40136 Bologna, Italy.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Zini
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Jaap M
authors.initials: JM
authors.lastname: Middeldorp
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Bauke
authors.initials: B
authors.lastname: Ylstra
authors.affiliation: Department of Epidemiology and Biostatistics, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Renee X
authors.initials: RX
authors.lastname: de Menezes
authors.affiliation: Department of Neurosurgery, Neuro-Oncology Research Group, VU University Medical Center, 1007MB Amsterdam, the Netherlands; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Würdinger
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands.
authors.forename: Gerrit A
authors.initials: GA
authors.lastname: Meijer
authors.affiliation: Department of Pathology, VU University Medical Center, 1007MB Amsterdam, the Netherlands; Exosomes Research Group, VU University Medical Center, 1007MB Amsterdam, the Netherlands. Electronic address: d.pegtel@vumc.nl.
authors.forename: D Michiel
authors.initials: DM
authors.lastname: Pegtel
mesh_terms: D000241:Adenosine / Q000737:chemistry / Q000378:metabolism; D001402:B-Lymphocytes / Q000378:metabolism; D019295:Computational Biology; D055354:Exosomes / Q000378:metabolism*; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D035683:MicroRNAs / Q000378:metabolism; D022661:RNA, Untranslated / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D014529:Uridine / Q000737:chemistry / Q000378:metabolism
chemical_list: D035683:MicroRNAs; D022661:RNA, Untranslated; D000241:Adenosine; D014529:Uridine