Chromodomain helicase binding protein 8 (Chd8) is a novel A-kinase anchoring protein expressed during rat cardiac development

PLoS One. 2012;7(10):e46316. doi: 10.1371/journal.pone.0046316. Epub 2012 Oct 10.


A-kinase anchoring proteins (AKAPs) bind the regulatory subunits of protein kinase A (PKA) and localize the holoenzyme to discrete signaling microdomains in multiple subcellular compartments. Despite emerging evidence for a nuclear pool of PKA that rapidly responds to activation of the PKA signaling cascade, only a few AKAPs have been identified that localize to the nucleus. Here we show a PKA-binding domain in the amino terminus of Chd8, and demonstrate subcellular colocalization of Chd8 with RII. RII overlay and immunoprecipitation assays demonstrate binding between Chd8-S and RIIα. Binding is abrogated upon dephosphorylation of RIIα. By immunofluorescence, we identified nuclear and perinuclear pools of Chd8 in HeLa cells and rat neonatal cardiomyocytes. We also show high levels of Chd8 mRNA in RNA extracted from post-natal rat hearts. These data add Chd8 to the short list of known nuclear AKAPs, and implicate a function for Chd8 in post-natal rat cardiac development.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Female
  • Heart / growth & development*
  • Humans
  • Immunoprecipitation
  • Microscopy, Confocal
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Myocardium / metabolism*
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / metabolism*
  • Phosphorylation
  • Pregnancy
  • Rats
  • Rats, Sprague-Dawley
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Subcellular Fractions / metabolism


  • Carrier Proteins
  • Chd8 protein, rat
  • Nuclear Proteins