Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P06889 (
Mol
)
630,302
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Synphilin-1 is linked to the pathogenesis of Parkinson's disease (PD) based on its identification as an alpha-synuclein (
PARK1
) and parkin (PARK2) interacting protein. Moreover, synphilin-1 is a component of Lewy bodies (LB) in brains of sporadic PD patients. Therefore, we performed a detailed mutation analysis of the synphilin-1 gene in 328 German familial and sporadic PD patients. In two apparently sporadic PD patients we deciphered a novel C to T transition in position 1861 of the coding sequence leading to an amino acid substitution from arginine to cysteine in position 621 (R621C). This mutation was absent in a total of 702 chromosomes of healthy German controls. To define a possible role of mutant synphilin-1 in the pathogenesis of PD we performed functional analyses in SH-SY5Y cells. We found synphilin-1 capable of producing cytoplasmic inclusions in transfected cells. Moreover we observed a significantly reduced number of inclusions in cells expressing C621 synphilin-1 compared with cells expressing wild-type (wt) synphilin-1, when subjected to proteasomal inhibition. C621 synphilin-1 transfected cells were more susceptible to staurosporine-induced cell death than cells expressing wt synphilin-1. Our findings argue in favour of a causative role of the R621C mutation in the synphilin-1 gene in PD and suggest that the formation of intracellular inclusions may be beneficial to cells and that a mutation in synphilin-1 that reduces this ability may sensitize neurons to cellular stress.
Hum
Mol
Genet 2003 Jun 01
PMID:Identification and functional characterization of a novel R621C mutation in the synphilin-1 gene in Parkinson's disease. 1276 Oct 37
Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons in the Substantia Nigra and the formation of ubiquitin- and alpha-synuclein (aSYN)-positive cytoplasmic inclusions called Lewy bodies (LBs). Although most PD cases are sporadic, families with genetic mutations have been found. Mutations in PARK7/DJ-1 have been associated with autosomal recessive early-onset PD, while missense mutations or duplications of aSYN (
PARK1
, PARK4) have been linked to dominant forms of the disease. In this study, we identify the E3 ubiquitin ligase tumor necrosis factor-receptor associated factor 6 (TRAF6) as a common player in genetic and sporadic cases. TRAF6 binds misfolded mutant DJ-1 and aSYN. Both proteins are substrates of TRAF6 ligase activity in vivo. Interestingly, rather than conventional K63 assembly, TRAF6 promotes atypical ubiquitin linkage formation to both PD targets that share K6-, K27- and K29- mediated ubiquitination. Importantly, TRAF6 stimulates the accumulation of insoluble and polyubiquitinated mutant DJ-1 into cytoplasmic aggregates. In human post-mortem brains of PD patients, TRAF6 protein colocalizes with aSYN in LBs. These results reveal a novel role for TRAF6 and for atypical ubiquitination in PD pathogenesis.
Hum
Mol
Genet 2010 Oct 01
PMID:TRAF6 promotes atypical ubiquitination of mutant DJ-1 and alpha-synuclein and is localized to Lewy bodies in sporadic Parkinson's disease brains. 2063 98
Both PINK1 and parkin are the responsible genes (PARK6 and PARK2, respectively) for familial early-onset Parkinson's disease (PD). Several lines of evidences have suggested that mitochondrial dysfunction would be associated with PD pathogenesis. Lewy body, one of PD pathological hallmarks, contains alpha-synuclein, a familial PD (
PARK1
/4)-gene product, which is eliminated by macroautophagy, while PINK1 and parkin coordinately mediate mitophagy (hereafter called as PINK1/parkin-mediated mitophagy) reported firstly by Youle's group. The mitochondrial quality control system is specific for elimination of damaged mitochondria especially in the loss of mitochondrial membrane potential induced by treatment with mitochondrial uncoupler like CCCP or FCCP. In this chapter, we summarized immunocytochemical methods to monitor the PINK1/parkin-mediated mitophagy using cultured cells.
Methods
Mol
Biol 2018
PMID:Immunocytochemical Monitoring of PINK1/Parkin-Mediated Mitophagy in Cultured Cells. 2836 83
Hereditary Parkinson's disease (PD) can be triggered by an autosomal dominant overdose of alpha-Synuclein (SNCA) as stressor or the autosomal recessive deficiency of PINK1 Serine/Threonine-phosphorylation activity as stress-response. We demonstrated the combination of PINK1-knockout with overexpression of SNCA
A53T
in double mutant (DM) mice to exacerbate locomotor deficits and to reduce lifespan. To survey posttranslational modifications of proteins underlying the pathology, brain hemispheres of old DM mice underwent quantitative label-free global proteomic mass spectrometry, focused on Ser/Thr-phosphorylations. As an exceptionally strong effect, we detected >300-fold reductions of phosphoThr1928 in MAP1B, a microtubule-associated protein, and a similar reduction of phosphoSer3781 in ANK2, an interactor of microtubules. MAP1B depletion is known to trigger perturbations of microtubular mitochondria trafficking, neurite extension, and synaptic function, so it was noteworthy that relevantly decreased phosphorylation was also detected for other microtubule and microfilament factors, namely MAP2
S1801
, MARK1
S394
, MAP1A
T1794
, KIF1A
S1537
, 4.1N
S541
, 4.1G
S86
, and ADD2
S528
. While the MAP1B heavy chain supports regeneration and growth cones, its light chain assists DAPK1-mediated autophagy. Interestingly, relevant phosphorylation decreases of DAPK2
S299
, VPS13D
S2429
, and VPS13C
S2480
in the DM brain affected regulators of autophagy, which are implicated in PD. Overall, significant downregulations were enriched for PFAM C2 domains, other kinases, and synaptic transmission factors upon automated bioinformatics, while upregulations were not enriched for selective motifs or pathways. Validation experiments confirmed the change of LC3 processing as reflection of excessive autophagy in DM brain, and dependence of ANK2/MAP1B expression on PINK1 levels. Our new data provide independent confirmation in a mouse model with combined
PARK1
/PARK4/PARK6 pathology that MAP1B/ANK2 phosphorylation events are implicated in Parkinsonian neurodegeneration. These findings expand on previous observations in
Drosophila melanogaster
that the MAP1B ortholog futsch in the presynapse is a primary target of the PARK8 protein LRRK2, and on a report that MAP1B is a component of the pathological Lewy body aggregates in PD patient brains. Similarly,
ANK2
gene locus variants are associated with the risk of PD, ANK2 interacts with PINK1/Parkin-target proteins such as MIRO1 or ATP1A2, and ANK2-derived peptides are potent inhibitors of autophagy.
Int J
Mol
Sci 2019 Jul 04
PMID:SerThr-PhosphoProteome of Brain from Aged PINK1-KO+A53T-SNCA Mice Reveals pT1928-MAP1B and pS3781-ANK2 Deficits, as Hub between Autophagy and Synapse Changes. 3127 79