The alpha subunits of Gz and Gi interact with the eyes absent transcription cofactor Eya2, preventing its interaction with the six class of homeodomain-containing proteins

J Biol Chem. 2000 Oct 13;275(41):32129-34. doi: 10.1074/jbc.M004577200.

Abstract

Yeast two-hybrid techniques were used to identify possible effectors for the heterotrimeric G protein G(z) in human bone marrow cells. Eya2, a human homologue of the Drosophila Eya transcription co-activator, was identified. Eya2 interacts with activated Galpha(z) and at least one other member of the Galpha(i) family, Galpha(i2). Interactions were confirmed in mammalian two-hybrid and glutathione S-transferase fusion protein pull-down assays. Regions of Eya2-mediating interaction were mapped to the C-terminal Eya consensus domain. Eya2 is an intrinsically cytosolic protein that is translocated to the nucleus by members of the Six homeodomain-containing family of proteins. Activated Galpha(z) and Galpha(i2) prevent Eya2 translocation and inhibit Six/Eya2-mediated activation of a reporter gene controlled through the MEF3/TATA promoter. Although G proteins are known to regulate the activity of numerous transcription factors, this regulation is normally achieved indirectly via one or more intermediates. We show here a novel functional regulation of a co-activator directly by G protein subunits.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Bone Marrow Cells / metabolism
  • Cell Nucleus / metabolism
  • Consensus Sequence
  • Cytosol / metabolism
  • Fluorescent Antibody Technique
  • GTP-Binding Protein alpha Subunits, Gi-Go / genetics
  • GTP-Binding Protein alpha Subunits, Gi-Go / metabolism*
  • Genes, Reporter / genetics
  • HeLa Cells
  • Heterotrimeric GTP-Binding Proteins / genetics
  • Heterotrimeric GTP-Binding Proteins / metabolism*
  • Homeodomain Proteins / metabolism*
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins / metabolism
  • Nuclear Proteins
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • Protein Subunits
  • Protein Transport
  • Protein Tyrosine Phosphatases
  • Trans-Activators / antagonists & inhibitors
  • Trans-Activators / chemistry
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Two-Hybrid System Techniques

Substances

  • Homeodomain Proteins
  • Intracellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Protein Subunits
  • SIX1 protein, human
  • SIX4 protein, human
  • Six1 protein, mouse
  • Trans-Activators
  • EYA2 protein, human
  • Eya2 protein, mouse
  • Protein Tyrosine Phosphatases
  • GTP-Binding Protein alpha Subunits, Gi-Go
  • Heterotrimeric GTP-Binding Proteins