Splicing factor arginine/serine-rich 17A (SFRS17A) is an A-kinase anchoring protein that targets protein kinase A to splicing factor compartments

J Biol Chem. 2009 Dec 11;284(50):35154-64. doi: 10.1074/jbc.M109.056465. Epub 2009 Oct 19.

Abstract

Protein kinase A (PKA) is targeted to distinct subcellular localizations by specific protein kinase A anchoring proteins (AKAPs). AKAPs are divided into subclasses based on their ability to bind type I or type II PKA or both. Dual-specificity AKAPs were recently reported to have an additional PKA binding determinant called the RI specifier region. A bioinformatic search with the consensus RI specifier region identified a novel AKAP, the splicing factor arginine/serine-rich 17A (SFRS17A). Here, we show by a variety of protein interaction assays that SFRS17A binds both type I and type II PKA in vitro and inside cells, demonstrating that SFRS17A is a dual-specific AKAP. Moreover, immunofluorescence experiments show that SFRS17A colocalizes with the catalytic subunit of PKA as well as the splicing factor SC35 in splicing factor compartments. Using the E1A minigene splicing assay, we found that expression of wild type SFRS17A conferred regulation of E1A alternative splicing, whereas the mutant SFRS17A, which is unable to bind PKA, did not. Our data suggest that SFRS17A is an AKAP involved in regulation of pre-mRNA splicing possibly by docking a pool of PKA in splicing factor compartments.

Publication types

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

MeSH terms

  • A Kinase Anchor Proteins / genetics
  • A Kinase Anchor Proteins / metabolism*
  • Alternative Splicing
  • Animals
  • Cattle
  • Cell Line
  • Cyclic AMP-Dependent Protein Kinases / genetics
  • Cyclic AMP-Dependent Protein Kinases / metabolism*
  • Enzyme Activation
  • Humans
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Protein Subunits / genetics
  • Protein Subunits / metabolism
  • RNA Precursors / genetics
  • RNA Precursors / metabolism
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Serine-Arginine Splicing Factors
  • Surface Plasmon Resonance

Substances

  • A Kinase Anchor Proteins
  • Nuclear Proteins
  • Protein Subunits
  • RNA Precursors
  • RNA-Binding Proteins
  • Recombinant Fusion Proteins
  • Serine-Arginine Splicing Factors
  • Cyclic AMP-Dependent Protein Kinases