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Repeat Kinase (repeat + kinase)
Kinds of Repeat Kinase Selected AbstractsA novel LRRK2 mutation in an Austrian cohort of patients with Parkinson's diseaseMOVEMENT DISORDERS, Issue 11 2007Dietrich Haubenberger MD Abstract To investigate the frequency of mutations in the Leucine-Rich Repeat Kinase 2 gene (LRRK2) in a sample of Austrian Parkinson's disease (PD) patients, we sequenced the complete coding region in 16 patients with autosomal dominant PD. Furthermore, we sequenced exons 31, 35, and 41 additionally in 146 patients with idiopathic PD and 30 patients with dementia with Lewy bodies. Furthermore, all 192 patients were screened for 21 putative LRRK2 mutations. While the most common mutation G2019S and the risk variant G2385R were not found in our samples, we detected a novel missense mutation (S973N) in a patient with familial, late-onset and dopa-responsive PD. © 2007 Movement Disorder Society [source] Screening for SNCA and LRRK2 mutations in Greek sporadic and autosomal dominant Parkinson's disease: identification of two novel LRRK2 variantsEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2007G. Xiromerisiou Mutations in SNCA and LRRK2 genes, encoding alpha-synuclein and leucine-rich repeat kinase 2, respectively, cause autosomal dominant Parkinson's disease (AdPD). The LRRK2 G2019S (c.6055G > A) and R1441G (c.4321C > G) mutations have also been identified in sporadic PD (sPD). We studied 55 unrelated patients with AdPD, 235 patients with sPD, and 235 healthy age- and gender-matched controls all of Greek origin. Patients with AdPD were screened for SNCA and LRRK2 mutations by direct sequencing. SNCA gene dosage analysis was also performed for AdPD using quantitative duplex polymerase chain reaction of genomic DNA. In addition, we investigated the frequency of the LRRK2 G2019S mutation in sPD. We found no missense mutations or multiplications in the SNCA gene. Here we report two novel variants, A211V (c.632C > T) and K544E (c.1630A > G) in LRRK2 gene in two patients with AdPD that was not present in controls. We identified only one patient with sPD (1/235; 0.4%) carrying the G2019S mutation. LRRK2 mutations are present in AdPD and sPD patients of Greek origin. [source] MAPK-pathway activity, Lrrk2 G2019S, and Parkinson's diseaseJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2007Linda R. White Abstract The 6055G>A mutation in the leucine-rich repeat kinase 2 (LRRK2) gene results in a G2019S substitution in the mixed-lineage kinase domain of Lrrk2, causing autosomal dominant Parkinson's disease (PD). We hypothesized the mutation alters cellular mitogen-activated protein kinase (MAPK) signalling cascades, and might be detectable in tissues other than in the brain. We therefore compared total levels and activation of the signalling proteins Src, HSP27, p38 MAPK, JNK, and ERK, in extracts of leukocytes isolated from patients with PD carrying the G2019S mutation, healthy mutation carriers, patients with idiopathic PD, and healthy controls. Phosphorylation of Src, HSP27, and JNK was reduced significantly in cell extracts from patients with G2019S-associated PD compared to healthy controls. Similarly, phosphorylation was reduced significantly in Src and HSP27 in the group of healthy carriers of the mutation, as well as in patients with idiopathic PD. Significant reductions in total Src were also observed in these three groups compared to the controls. The results of this pilot project therefore indicate significant alterations in key signalling proteins in leukocytes from patients with PD, and were most pronounced in G2019S-associated PD. Changes in MAPK-signalling may thus be common to PD pathophysiology, regardless of aetiology. Such changes may also be shown in blood samples during the preclinical stage of LRRK2 -associated PD, which could be particularly important for the development of neuroprotective strategies to delay onset, or slow progression of PD. © 2007 Wiley-Liss, Inc. [source] LRRK2 mutations and risk variants in Japanese patients with Parkinson's disease,MOVEMENT DISORDERS, Issue 7 2009Cyrus P. Zabetian MD Abstract Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most common genetic determinant of Parkinson's disease (PD) in European-derived populations, but far less is known about LRRK2 mutations and susceptibility alleles in Asians. To address this issue, we sequenced the LRRK2 coding region in 36 patients with familial PD, then genotyped variants of interest in an additional 595 PD cases and 1,641 controls who were all of Japanese ancestry. We also performed a meta-analysis of studies on G2385R, a polymorphism previously reported to associate with PD. One pathogenic (G2019S) and one putative pathogenic (R1067Q) mutation were each observed in two patients with sporadic PD. The overall mutation frequency among patients was 0.6%. G2385R was highly associated with PD under a dominant model in our dataset (adjusted OR, 1.83; 95% CI, 1.31,2.54; P = 3.3 × 10,4) and similar results were seen in the meta-analysis (summary OR assuming fixed effects, 2.55; 95% CI, 2.10,3.10). G2385R represents the first consistently replicated common PD susceptibility variant in a non-European population and its effect size is substantially greater than that reported for other well-validated genetic risk factors for the disease. However, LRRK2 mutations appear to be rare among Japanese patients with PD. © 2009 Movement Disorder Society [source] LRRK2 is a component of granular alpha-synuclein pathology in the brainstem of Parkinson's diseaseNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2008J. Alegre-Abarrategui Classical Parkinson's disease (PD) is characterized by the appearance of Lewy bodies (LBs) in affected brain regions, showing mostly compact alpha-synuclein deposition, in contrast with punctate or granular deposition, hypothesized to represent early stages of aggregation. Leucine-rich repeat kinase 2 (LRRK2) is the commonest mutated gene in inherited and idiopathic PD. LRRK2 mutation carriers display a diverse neuropathology, including alpha-synuclein and tau inclusions, suggesting an upstream role for LRRK2 in protein aggregation. We studied LRRK2 expression throughout the normal human brain with three different antibodies. We also examined the pattern of LRRK2 expression in relation to alpha-synuclein aggregation and LB formation in the brainstem of sporadic LB disease. Physiological LRRK2 expression was not restricted to regions preferentially affected in PD and LRRK2 often localized to the nuclear envelope in addition to the known cytoplasmic expression. In PD, we were able to consistently detect LRRK2 in the halo of a minority (approximately 10%) of nigral LBs using three different antibodies. Only one antibody detected LRRK2 in the core of approximately 80% of classic LBs. In the lower brainstem, most notably in the dorsal motor nucleus of the vagus, we found previously unrecognized LRRK2 labelling of complex globular lesions, filled with LB-like matter showing a punctate or granular staining for alpha-synuclein. This was often accompanied by strong LRRK2 expression within dystrophic neurites. Our findings confirm widespread physiological LRRK2 expression in the human brain and suggest an association of LRRK2 with possible early-stage alpha-synuclein pathology in the brainstem of PD. [source] Mechanisms in dominant parkinsonism: The toxic triangle of LRRK2, ,-synuclein, and tauBIOESSAYS, Issue 3 2010Jean-Marc Taymans Abstract Parkinson's disease (PD) is generally sporadic but a number of genetic diseases have parkinsonism as a clinical feature. Two dominant genes, ,-synuclein (SNCA) and leucine-rich repeat kinase 2 (LRRK2), are important for understanding inherited and sporadic PD. SNCA is a major component of pathologic inclusions termed Lewy bodies found in PD. LRRK2 is found in a significant proportion of PD cases. These two proteins may be linked as most LRRK2 PD cases have SNCA -positive Lewy bodies. Mutations in both proteins are associated with toxic effects in model systems although mechanisms are unclear. LRRK2 is an intracellular signaling protein possessing both GTPase and kinase activities that may contribute to pathogenicity. A third protein, tau, is implicated as a risk factor for PD. We discuss the potential relationship between these genes and suggest a model for PD pathogenesis where LRRK2 is upstream of pathogenic effects through SNCA, tau, or both proteins. [source] |