abstract |
Catalytic domain of the Serine/Threonine Kinase, Leucine-Rich Repeat Kinase 2. STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. LRRK2 is one of two vertebrate LRRKs which show complementary expression in the brain. Mutations in LRRK2, found in the kinase, ROC-COR, and WD40 domains, are linked to both familial and sporadic forms of Parkinson's disease. The most prevalent mutation, G2019S located in the activation loop of the kinase domain, increases kinase activity. The R1441C/G mutations in the GTPase domain have also been reported to influence kinase activity. LRRKs are also classified as ROCO proteins because they contain a ROC (Ras of complex proteins)/GTPase domain followed by a COR (C-terminal of ROC) domain of unknown function. In addition, LRRKs contain a catalytic kinase domain and protein-protein interaction motifs including a WD40 domain, LRRs and ankyrin (ANK) repeats. LRRKs possess both GTPase and kinase activities, with the ROC domain acting as a molecular switch for the kinase domain, cycling between a GTP-bound state which drives kinase activity and a GDP-bound state which decreases the activity. The LRRK2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase. |