Massively parallel sequencing of human urinary exosome/microvesicle RNA reveals a predominance of non-coding RNA

PLoS One. 2014 May 9;9(5):e96094. doi: 10.1371/journal.pone.0096094. eCollection 2014.

Abstract

Intact RNA from exosomes/microvesicles (collectively referred to as microvesicles) has sparked much interest as potential biomarkers for the non-invasive analysis of disease. Here we use the Illumina Genome Analyzer to determine the comprehensive array of nucleic acid reads present in urinary microvesicles. Extraneous nucleic acids were digested using RNase and DNase treatment and the microvesicle inner nucleic acid cargo was analyzed with and without DNase digestion to examine both DNA and RNA sequences contained in microvesicles. Results revealed that a substantial proportion (∼87%) of reads aligned to ribosomal RNA. Of the non-ribosomal RNA sequences, ∼60% aligned to non-coding RNA and repeat sequences including LINE, SINE, satellite repeats, and RNA repeats (tRNA, snRNA, scRNA and srpRNA). The remaining ∼40% of non-ribosomal RNA reads aligned to protein coding genes and splice sites encompassing approximately 13,500 of the known 21,892 protein coding genes of the human genome. Analysis of protein coding genes specific to the renal and genitourinary tract revealed that complete segments of the renal nephron and collecting duct as well as genes indicative of the bladder and prostate could be identified. This study reveals that the entire genitourinary system may be mapped using microvesicle transcript analysis and that the majority of non-ribosomal RNA sequences contained in microvesicles is potentially functional non-coding RNA, which play an emerging role in cell regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromosome Mapping
  • Exosomes / genetics*
  • Genome, Human / genetics
  • High-Throughput Nucleotide Sequencing / methods*
  • Humans
  • Male
  • Oligonucleotide Array Sequence Analysis / methods
  • RNA / chemistry
  • RNA / genetics*
  • RNA / urine
  • RNA, Ribosomal / chemistry
  • RNA, Ribosomal / genetics
  • RNA, Ribosomal / urine
  • RNA, Untranslated / chemistry
  • RNA, Untranslated / genetics*
  • RNA, Untranslated / urine
  • Repetitive Sequences, Nucleic Acid / genetics
  • Transcriptome
  • Urogenital System / metabolism

Substances

  • RNA, Ribosomal
  • RNA, Untranslated
  • RNA

Grants and funding

This research was supported by the Juvenile Diabetes Research Foundation International Innovation Award (LMR, KCM) 5-2008-722. LMR Received a Juvenile Diabetes Research Foundation International Transition Award (10-2006-75). KCM received a National Kidney Foundation Postdoctoral Fellowship Award. This work was presented in part at the American Society of Nephrology Annual Meeting. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.