LRRK2 Facilitates tau Phosphorylation through Strong Interaction with tau and cdk5.
Leucine-rich repeat kinase 2 (LRRK2) and tau have been identified as risk factors of Parkinson's disease (PD). As LRRK2 is a kinase and tau is hyperphosphorylated in some LRRK2 mutation carriers of PD patients, the obvious hypothesis is that tau could be a substrate of LRRK2. Previous reports that LRRK2 phosphorylates free tau or tubulin-associated tau provide direct support for this proposition. By comparing LRRK2 with cdk5, we show that wild-type LRRK2 and the G2019S mutant phosphorylate free recombinant full-length tau protein with specific activity 480- and 250-fold lower than cdk5, respectively. More strikingly tau binds to wt LRRK2 or the G2019S mutant 140- or 200-fold more strongly than cdk5. The extremely low activity of LRRK2 but strong binding affinity with tau suggests that LRRK2 may facilitate tau phosphorylation as a scaffold protein rather than as a major tau kinase. This hypothesis is further supported by the observation that (i) cdk5 or tau coimmunoprecipitates with endogenous LRRK2 in SH-SY5Y cells, in mouse brain tissue, and in human PBMCs; (ii) knocking down endogenous LRRK2 by its siRNA in SH-SY5Y cells reduces tau phosphorylation at Ser396 and Ser404; (iii) inhibiting LRRK2 kinase activity by its inhibitors has no effect on tau phosphorylation at these two sites; and (iv) overexpressing wt LRRK2, the G2019S mutant, or the D1994A kinase-dead mutant in SH-SY5Y cells has no effect on tau phosphorylation. Our results suggest that LRRK2 facilitates tau phosphorylation indirectly by recruiting tau or cdk5 rather than by directly phosphorylating tau.
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Mary R
MR
Shanley
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Dillon
D
Hawley
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Shirley
S
Leung
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Nikhat F
NF
Zaidi
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Roshni
R
Dave
Department of Genetics and of Biochemistry, Geisel School of Medicine at Dartmouth , One Medical Center Drive HB-7937, Lebanon, New Hampshire 03756, United States.
Kate A
KA
Schlosser
Reta Lila, Weston Institute of Neurological Studies Department of Molecular Neuroscience UCL, Institute of Neurology 1 , Wakefield Street, London WC1N 1PJ, U.K.
Rina
R
Bandopadhyay
Department of Genetics and of Biochemistry, Geisel School of Medicine at Dartmouth , One Medical Center Drive HB-7937, Lebanon, New Hampshire 03756, United States.
Scott A
SA
Gerber
Neurology Department, Brigham and Women's Hospital, Harvard Medical School , 65 Landsdowne Street, Fourth Floor, Cambridge, Massachusetts 02139, United States.
Min
M
Liu
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D055162:Biocatalysis; D001921:Brain / Q000378:metabolism; D045744:Cell Line, Tumor; D051360:Cyclin-Dependent Kinase 5 / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D010300:Parkinson Disease / Q000235:genetics; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014404:Tubulin / Q000378:metabolism; D016875:tau Proteins / Q000378:metabolism*
D014404:Tubulin; D016875:tau Proteins; D051360:Cyclin-Dependent Kinase 5; C495280:LRRK2 protein, human; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; C495279:Lrrk2 protein, mouse; D017346:Protein Serine-Threonine Kinases