Parkinson disease-associated mutation R1441H in LRRK2 prolongs the "active state" of its GTPase domain

Proc Natl Acad Sci U S A. 2014 Mar 18;111(11):4055-60. doi: 10.1073/pnas.1323285111. Epub 2014 Mar 3.

Abstract

Mutation in leucine-rich-repeat kinase 2 (LRRK2) is a common cause of Parkinson disease (PD). A disease-causing point mutation R1441H/G/C in the GTPase domain of LRRK2 leads to overactivation of its kinase domain. However, the mechanism by which this mutation alters the normal function of its GTPase domain [Ras of complex proteins (Roc)] remains unclear. Here, we report the effects of R1441H mutation (RocR1441H) on the structure and activity of Roc. We show that Roc forms a stable monomeric conformation in solution that is catalytically active, thus demonstrating that LRRK2 is a bona fide self-contained GTPase. We further show that the R1441H mutation causes a twofold reduction in GTPase activity without affecting the structure, thermal stability, and GDP-binding affinity of Roc. However, the mutation causes a twofold increase in GTP-binding affinity of Roc, thus suggesting that the PD-causing mutation R1441H traps Roc in a more persistently activated state by increasing its affinity for GTP and, at the same time, compromising its GTP hydrolysis.

Keywords: dimer; monomer; neurodegenerative disease; oligomeric states.

Publication types

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

MeSH terms

  • Blotting, Western
  • Chromatography, Gel
  • Circular Dichroism
  • Dimerization
  • Electrophoresis, Polyacrylamide Gel
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism*
  • Humans
  • Leucine-Rich Repeat Serine-Threonine Protein Kinase-2
  • Mass Spectrometry
  • Models, Molecular*
  • Mutation, Missense / genetics*
  • Parkinson Disease / genetics*
  • Protein Conformation*
  • Protein-Serine-Threonine Kinases / chemistry
  • Protein-Serine-Threonine Kinases / genetics*
  • Protein-Serine-Threonine Kinases / metabolism

Substances

  • LRRK2 protein, human
  • Leucine-Rich Repeat Serine-Threonine Protein Kinase-2
  • Protein-Serine-Threonine Kinases
  • GTP Phosphohydrolases