title: Functional properties of LRRK2 mutations in Taiwanese Parkinson disease.
abstract: OBJECTIVE
  Leucine-rich repeat kinase 2 (LRRK2) is a large protein encoding multiple functional domains. Mutations within different LRRK2 domains have been considered to be involved in the development of Parkinson disease by different mechanisms. Our previous study found three LRRK2 mutations-p.R767H, p.S885N, and p.R1441H-in Taiwanese patients with Parkinson disease.
  
  
  METHODS
  We evaluated the functional properties of LRRK2 p.R767H, p.S885N, and p.R1441H mutations by overexpressing them in human embryonic kidney 293 and neuroblastoma SK-N-SH cells. The common p.G2019S mutation in the kinase domain was included for comparison.
  
  
  RESULTS
  In 293 cells, overexpressed p.R1441H-but not p.R767H, p.S885N, or p.G2019-increased GTP binding affinity to prolong the active state. Overexpressed p.R1441H and p.G2019S generated inclusions in 293 cells. In SK-N-SH cells, the α-synuclein was coexpressed with wild type as well as mutated p.R767H, p.S885N, p.R1441H, and p.G2019 LRRK2 proteins. Part of the perinuclear inclusions formed by p.R1441H and p.G2019S were colocalized with α-synuclein. Additionally, p.S885N and p.R1441H mutations caused reduced interaction between LRRK2 and ARHGEF7, a putative guanine nucleotide exchange factor for LRRK2, whereas this interaction was well preserved in p.R767H and p.G2019S mutations.
  
  
  CONCLUSIONS
  Our study suggests that p.R1441H protein facilitates the formation of intracellular inclusions, compromises GTP hydrolysis by increasing its affinity for GTP, and reduces its interaction with ARHGEF7.
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital-Linkou Medical Center, Chang Gung University College of Medicine, Taipei 10507, Taiwan.
authors.forename: Kuo-Hsuan
authors.initials: KH
authors.lastname: Chang
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital-Linkou Medical Center, Chang Gung University College of Medicine, Taipei 10507, Taiwan.
authors.forename: Chiung-Mei
authors.initials: CM
authors.lastname: Chen
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital-Linkou Medical Center, Chang Gung University College of Medicine, Taipei 10507, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Lin
authors.affiliation: Department of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan.
authors.forename: Wen-Teng
authors.initials: WT
authors.lastname: Chang
authors.affiliation: Department of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan.
authors.forename: Pei-Ru
authors.initials: PR
authors.lastname: Jiang
authors.affiliation: Department of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan.
authors.forename: Ya-Chin
authors.initials: YC
authors.lastname: Hsiao
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital-Linkou Medical Center, Chang Gung University College of Medicine, Taipei 10507, Taiwan. Electronic address: yihruwu@cgmh.org.tw.
authors.forename: Yih-Ru
authors.initials: YR
authors.lastname: Wu
authors.affiliation: Department of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan. Electronic address: t43019@ntnu.edu.tw.
authors.forename: Guey-Jen
authors.initials: GJ
authors.lastname: Lee-Chen
mesh_terms: D020558:GTP Phosphohydrolases / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 / Q000235:genetics*; D020125:Mutation, Missense; D010300:Parkinson Disease / Q000235:genetics* / Q000503:physiopathology*; D064067:Rho Guanine Nucleotide Exchange Factors / Q000235:genetics*; D013624:Taiwan
chemical_list: C576606:ARHGEF7 protein, human; D064067:Rho Guanine Nucleotide Exchange Factors; C495280:LRRK2 protein, human; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D020558:GTP Phosphohydrolases
keywords: ARHGEF7; GTPase; LRRK2; Parkinson disease; p.R1441H mutation