A sliding docking interaction is essential for sequential and processive phosphorylation of an SR protein by SRPK1

Mol Cell. 2008 Mar 14;29(5):563-76. doi: 10.1016/j.molcel.2007.12.017.

Abstract

The 2.9 A crystal structure of the core SRPK1:ASF/SF2 complex reveals that the N-terminal half of the basic RS domain of ASF/SF2, which is destined to be phosphorylated, is bound to an acidic docking groove of SRPK1 distal to the active site. Phosphorylation of ASF/SF2 at a single site in the C-terminal end of the RS domain generates a primed phosphoserine that binds to a basic site in the kinase. Biochemical experiments support a directional sliding of the RS peptide through the docking groove to the active site during phosphorylation, which ends with the unfolding of a beta strand of the RRM domain and binding of the unfolded region to the docking groove. We further suggest that the priming of the first serine facilitates directional substrate translocation and efficient phosphorylation.

Publication types

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

MeSH terms

  • Adenylyl Imidodiphosphate / chemistry
  • Adenylyl Imidodiphosphate / metabolism
  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Crystallography, X-Ray
  • Humans
  • Mice
  • Models, Molecular
  • Molecular Sequence Data
  • Multiprotein Complexes / metabolism
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Phosphorylation
  • Protein Binding
  • Protein Structure, Tertiary*
  • Protein-Serine-Threonine Kinases / chemistry*
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • RNA-Binding Proteins
  • Ribonucleoside Diphosphate Reductase / chemistry
  • Ribonucleoside Diphosphate Reductase / genetics
  • Ribonucleoside Diphosphate Reductase / metabolism
  • Sequence Alignment
  • Serine-Arginine Splicing Factors

Substances

  • Multiprotein Complexes
  • Nuclear Proteins
  • RNA-Binding Proteins
  • Serine-Arginine Splicing Factors
  • Adenylyl Imidodiphosphate
  • ribonucleotide reductase M2
  • Ribonucleoside Diphosphate Reductase
  • SRPK1 protein, human
  • Protein-Serine-Threonine Kinases