Structural and functional mapping of Rtg2p determinants involved in retrograde signaling and aging of Saccharomyces cerevisiae

PLoS One. 2017 May 4;12(5):e0177090. doi: 10.1371/journal.pone.0177090. eCollection 2017.

Abstract

In Saccharomyces cerevisiae mitochondrial dysfunction induces retrograde signaling, a pathway of communication from mitochondria to the nucleus that promotes a metabolic remodeling to ensure sufficient biosynthetic precursors for replication. Rtg2p is a positive modulator of this pathway that is also required for cellular longevity. This protein belongs to the ASKHA superfamily, and contains a putative N-terminal ATP-binding domain, but there is no detailed structural and functional map of the residues in this domain that accounts for their contribution to retrograde signaling and aging. Here we use Decomposition of Residue Correlation Networks and site-directed mutagenesis to identify Rtg2p structural determinants of retrograde signaling and longevity. We found that most of the residues involved in retrograde signaling surround the ATP-binding loops, and that Rtg2p N-terminus is divided in three regions whose mutants have different aging phenotypes. We also identified E137, D158 and S163 as possible residues involved in stabilization of ATP at the active site. The mutants shown here may be used to map other Rtg2p activities that crosstalk to other pathways of the cell related to genomic stability and aging.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Amino Acid Sequence
  • Binding Sites
  • Crystallography, X-Ray
  • Intracellular Signaling Peptides and Proteins / chemistry
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism*
  • Models, Molecular
  • Mutation
  • Protein Conformation
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Signal Transduction*

Substances

  • Intracellular Signaling Peptides and Proteins
  • RTG2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Adenosine Triphosphate

Grants and funding

This work was supported by Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (www.fapesp.br) to JRFJ.