A Glutamine/Asparagine-Rich Fragment of Gln3, but not the Full-Length Protein, Aggregates in Saccharomyces cerevisiae

Biochemistry (Mosc). 2016 Apr;81(4):407-13. doi: 10.1134/S0006297916040118.


The amino acid sequence of protein Gln3 in yeast Saccharomyces cerevisiae has a region enriched with Gln (Q) and Asn (N) residues. In this study, we analyzed the effects of overexpression of Gln3 and its Q/N-rich fragment fused with yellow fluorescent protein (YFP). Being overexpressed, full-length Gln3-YFP does not form aggregates, inhibits vegetative growth, and demonstrates nuclear localization, while the Q/N-rich fragment (Gln3QN) fused with YFP forms aggregates that do not colocalize with the nucleus and do not affect growth of the cells. Although detergent-resistant aggregates of Gln3QN are formed in the absence of yeast prions, the aggregation of Gln3QN significantly increases in the presence of [PIN(+)] prion, while in the presence of two prions, [PSI(+)] and [PIN(+)], the percentage of cells with Gln3QN aggregates is significantly lower than in the strain bearing only [PIN(+)]. Data on colocalization demonstrate that this effect is mediated by interaction between Gln3QN aggregates and [PSI(+)] and [PIN(+)] prions.

MeSH terms

  • Amino Acid Sequence
  • Asparagine / metabolism*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Cell Nucleus / metabolism
  • Glutamine / metabolism*
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Peptide Termination Factors / chemistry
  • Peptide Termination Factors / metabolism
  • Prions / chemistry
  • Prions / metabolism
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / isolation & purification
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Transcription Factors / chemistry
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • Bacterial Proteins
  • GLN3 protein, S cerevisiae
  • Luminescent Proteins
  • Peptide Termination Factors
  • Prions
  • RNQ1 protein, S cerevisiae
  • Recombinant Fusion Proteins
  • SUP35 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • yellow fluorescent protein, Bacteria
  • Glutamine
  • Asparagine