Retrotransposon profiling of RNA polymerase III initiation sites

Genome Res. 2012 Apr;22(4):681-92. doi: 10.1101/gr.131219.111. Epub 2012 Jan 27.

Abstract

Although retroviruses are relatively promiscuous in choice of integration sites, retrotransposons can display marked integration specificity. In yeast and slime mold, some retrotransposons are associated with tRNA genes (tDNAs). In the Saccharomyces cerevisiae genome, the long terminal repeat retrotransposon Ty3 is found at RNA polymerase III (Pol III) transcription start sites of tDNAs. Ty1, 2, and 4 elements also cluster in the upstream regions of these genes. To determine the extent to which other Pol III-transcribed genes serve as genomic targets for Ty3, a set of 10,000 Ty3 genomic retrotranspositions were mapped using high-throughput DNA sequencing. Integrations occurred at all known tDNAs, two tDNA relics (iYGR033c and ZOD1), and six non-tDNA, Pol III-transcribed types of genes (RDN5, SNR6, SNR52, RPR1, RNA170, and SCR1). Previous work in vitro demonstrated that the Pol III transcription factor (TF) IIIB is important for Ty3 targeting. However, seven loci that bind the TFIIIB loader, TFIIIC, were not targeted, underscoring the unexplained absence of TFIIIB at those sites. Ty3 integrations also occurred in two open reading frames not previously associated with Pol III transcription, suggesting the existence of a small number of additional sites in the yeast genome that interact with Pol III transcription complexes.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Base Sequence
  • Binding Sites / genetics
  • DNA Polymerase III / genetics*
  • DNA Polymerase III / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Fungal
  • Genome, Fungal / genetics
  • High-Throughput Nucleotide Sequencing / methods
  • Models, Genetic
  • Mutagenesis, Insertional*
  • Oligonucleotide Array Sequence Analysis
  • Recombination, Genetic
  • Retroelements / genetics*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Sequence Homology, Nucleic Acid
  • Transcription Factor TFIIIB / genetics
  • Transcription Factor TFIIIB / metabolism
  • Transcription Initiation Site
  • Transcription, Genetic

Substances

  • POL3 protein, S cerevisiae
  • Retroelements
  • Saccharomyces cerevisiae Proteins
  • Transcription Factor TFIIIB
  • DNA Polymerase III

Associated data

  • GEO/GSE31820