Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mutations in PTEN-induced putative kinase 1 (PINK1) are a cause of autosomal recessive familial Parkinson's disease (PD). Efforts in deducing the PINK1 signaling pathway have been hindered by controversy around its subcellular and submitochondrial localization and the authenticity of its reported substrates. We show here that this mitochondrial protein exhibits a topology in which the kinase domain faces the cytoplasm and the N-terminal tail is inside the mitochondria. Although deletion of the transmembrane domain disrupts this topology, common PD-linked PINK1 mutations do not. These results are critical in rectifying the location and orientation of PINK1 in mitochondria, and they should help decipher its normal physiological function and potential pathogenic role in PD.
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PMID:The kinase domain of mitochondrial PINK1 faces the cytoplasm. 1868 99

Parkinson's disease (PD) is a common neurodegenerative disorder thought to be associated with mitochondrial dysfunction. Loss of function mutations in the putative mitochondrial protein PINK1 (PTEN-induced kinase 1) have been linked to familial forms of PD, but the relation of PINK1 to mammalian mitochondrial function remains unclear. Here, we report that germline deletion of the PINK1 gene in mice significantly impairs mitochondrial functions. Quantitative electron microscopic studies of the striatum in PINK1(-/-) mice at 3-4 and 24 months revealed no gross changes in the ultrastructure or the total number of mitochondria, although the number of larger mitochondria is selectively increased. Functional assays showed impaired mitochondrial respiration in the striatum but not in the cerebral cortex at 3-4 months of age, suggesting specificity of this defect for dopaminergic circuitry. Aconitase activity associated with the Krebs cycle is also reduced in the striatum of PINK1(-/-) mice. Interestingly, mitochondrial respiration activities in the cerebral cortex are decreased in PINK1(-/-) mice at 2 years compared with control mice, indicating that aging can exacerbate mitochondrial dysfunction in these mice. Furthermore, mitochondrial respiration defects can be induced in the cerebral cortex of PINK1(-/-) mice by cellular stress, such as exposure to H(2)O(2) or mild heat shock. Together, our findings demonstrate that mammalian PINK1 is important for mitochondrial function and provides critical protection against both intrinsic and environmental stress, suggesting a pathogenic mechanism by which loss of PINK1 may lead to nigrostriatal degeneration in PD.
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PMID:Loss of PINK1 causes mitochondrial functional defects and increased sensitivity to oxidative stress. 1868 3

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder in the Western world. PTEN (phosphatase/tensin homolog on chromosome 10)-induced putative kinase 1 (PINK1), a putative kinase that is mutated in autosomal recessive forms of PD, is also implicated in sporadic cases of the disease. Although the mutations appear to result in a loss of function, the roles of this protein and the pathways involved in PINK1 PD are poorly understood. Here, we generated a vertebrate model of PINK1 insufficiency using morpholino oligonucleotide knockdown in zebrafish (Danio rerio). PINK1 knockdown results in a severe developmental phenotype that is rescued by wild-type human PINK1 mRNA. Morphants display a moderate decrease in the numbers of central dopaminergic neurons and alterations of mitochondrial function, including increases in caspase-3 activity and reactive oxygen species (ROS) levels. When the morphants were exposed to several drugs with antioxidant properties, ROS levels were normalized and the associated phenotype improved. In addition, GSK3beta-related mechanisms can account for some of the effects of PINK1 knockdown, as morphant fish show elevated GSK3beta activity and their phenotype is partially abrogated by GSK3beta inhibitors, such as LiCl and SB216763 [3-(2,4-dichlorophenyl)-4-(1-methyl-1H-indol-3-yl)1H-pyrrole-2,5-dione]. This provides new insights into the biology of PINK1 and a possible therapeutic avenue for further investigation.
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PMID:Loss of PINK1 function affects development and results in neurodegeneration in zebrafish. 1870 82

Parkinson disease (PD) is the most common neurodegenerative disease, and the majority of PD cases involve the sporadic from of PD. Although the etiology of the sporadic form is unknown, mitochondrial dysfunction and oxidative stress are considered to play a prominent role in its pathogenesis. The discovery of the genes that are linked to the rare familial form of PD has provided crucial insights into the molecular mechanisms involved in the pathogenesis of PD. Recent findings implicate mitochondrial dysfunction associated with oxidative damage (mitochondrial pathway) and abnormal protein accumulation (ubiquitin/ proteosome pathway) as the key molecular mechanisms compromising dopaminergic neurons in familial PD. Mutations in Parkin, PTEN-induced kinase 1 (PINK1) and DJ-1 are found in autosomal recessive forms of PD. Recent studies on these genes suggest the central importance of mitochondrial dysfunction and oxidative stress in PD. The above mentioned 3 proteins may be biologically related to each other and may protect the mitochondria against oxidative stress and other harmful stimulations. In particular, parkin appears to be the most important factor that improves the mitochondrial dysfunction. In this review we focus on the mitochondria and parkin function. We also provide an overview of the most relevant findings in recent years.
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PMID:[Parkin and mitochondria]. 1871 96

Mutations in PTEN-induced kinase 1 (pink1) or parkin cause autosomal-recessive and some sporadic forms of Parkinson's disease. pink1 acts upstream of parkin in a common genetic pathway to regulate mitochondrial integrity in Drosophila. Mitochondrial morphology is maintained by a dynamic balance between the opposing actions of mitochondrial fusion, controlled by Mitofusin (mfn) and Optic atrophy 1 (opa1), and mitochondrial fission, controlled by drp1. Here, we explore interactions between pink1/parkin and the mitochondrial fusion/fission machinery. Muscle-specific knockdown of the fly homologue of Mfn (Marf) or opa1, or overexpression of drp1, results in significant mitochondrial fragmentation. Mfn-knockdown flies also display altered cristae morphology. Interestingly, knockdown of Mfn or opa1 or overexpression of drp1, rescues the phenotypes of muscle degeneration, cell death, and mitochondrial abnormalities in pink1 or parkin mutants. In the male germline, we also observe genetic interactions between pink1 and the testes-specific mfn homologue fuzzy onion, and between pink1 and drp1. Our data suggest that the pink1/parkin pathway promotes mitochondrial fission and/or inhibits fusion by negatively regulating mfn and opa1 function, and/or positively regulating drp1. However, pink1 and parkin mutant flies show distinct mitochondrial phenotypes from drp1 mutant flies, and flies carrying a heterozygous mutation in drp1 enhance the pink1-null phenotype, resulting in lethality. These results suggest that pink1 and parkin are likely not core components of the drp1-mediated mitochondrial fission machinery. Modification of fusion and fission may represent a novel therapeutic strategy for Parkinson's disease.
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PMID:The Parkinson's disease genes pink1 and parkin promote mitochondrial fission and/or inhibit fusion in Drosophila. 1879 31

PTEN-induced putative kinase 1 (PINK1) and Parkin, encoded by their respective genes associated with Parkinson's disease (PD), are linked in a common pathway involved in the protection of mitochondrial integrity and function. However, the mechanism of their interaction at the biochemical level has not been investigated yet. Using both mammalian and Drosophila systems, we here demonstrate that the PINK1 kinase activity is required for its function in mitochondria. PINK1 regulates the localization of Parkin to the mitochondria in its kinase activity-dependent manner. In detail, Parkin phosphorylation by PINK1 on its linker region promotes its mitochondrial translocation, and the RING1 domain of Parkin is critical for this occurrence. These results demonstrate the biochemical relationship between PINK1, Parkin, and the mitochondria and thereby suggest the possible mechanism of PINK-Parkin-associated PD pathogenesis.
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PMID:PINK1 controls mitochondrial localization of Parkin through direct phosphorylation. 1895 82

Rare, inherited mutations causing familial forms of Parkinson's disease have provided insight into the molecular mechanisms that underlie the genetic and sporadic forms of this disease. Loss of protein function resulting from autosomal-recessive mutations in PTEN-induced putative kinase 1 (PINK1), Parkin and DJ-1 has been linked to mitochondrial dysfunction, accumulation of abnormal and misfolded proteins, impaired protein clearance and oxidative stress. Accumulating evidence suggests that wild-type PINK1, Parkin and DJ-1 may be key components of neuroprotective signalling cascades that run in parallel, interact via cross talk or converge in a common pathway.
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PMID:Emerging pathways in genetic Parkinson's disease: autosomal-recessive genes in Parkinson's disease--a common pathway? 1902 53

Parkinson's disease (PD) is a common neurodegenerative disorder caused by loss of midbrain dopaminergic neurons, the pathogenetic mechanisms of which remain unclear. Mitochondrial dysfunction, which has long been implicated in sporadic PD, has recently been highlighted as a key pathological cause, particularly with the identification of mutations in the PTEN-induced putative kinase (pink1), parkin and htrA2 (also known as omi) genes that are linked to PD. Studies in Drosophila melanogaster have shown that pink1 and parkin act in a common genetic pathway that maintains mitochondrial integrity, but other upstream or downstream components of this pathway are currently unknown. Using ectopic expression in the Drosophila eye as an assay, we have investigated the involvement of the mitochondrial protease encoded by omi in the Pink1/Parkin pathway and found that it acts genetically downstream of pink1 but functions independently of Parkin. Using the same approach, we also found that Rhomboid-7, a mitochondrial protease not previously implicated in PD, acts as an upstream component of this pathway, and showed that it is required to cleave the precursor forms of both Pink1 and Omi. These data further elucidate the composition of the Pink1 pathway and suggest that regulated intramembrane proteolysis is involved in its regulation.
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PMID:Rhomboid-7 and HtrA2/Omi act in a common pathway with the Parkinson's disease factors Pink1 and Parkin. 1904 81

The two Parkinson's disease (PD) genes, PTEN-induced kinase 1 (PINK1) and parkin, are linked in a common pathway which affects mitochondrial integrity and function. However, it is still not known what this pathway does in the mitochondria. Therefore, we investigated its physiological function in Drosophila. Because Drosophila PINK1 and parkin mutants show changes in mitochondrial morphology in both indirect flight muscles and dopaminergic neurons, we here investigated whether the PINK1-Parkin pathway genetically interacts with the regulators of mitochondrial fusion and fission such as Drp1, which promotes mitochondrial fission, and Opa1 or Marf, which induces mitochondrial fusion. Surprisingly, DrosophilaPINK1 and parkin mutant phenotypes were markedly suppressed by overexpression of Drp1 or downregulation of Opa1 or Marf, indicating that the PINK1-Parkin pathway regulates mitochondrial remodeling process in the direction of promoting mitochondrial fission. Therefore, we strongly suggest that mitochondrial fusion and fission process could be a prominent therapeutic target for the treatment of PD.
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PMID:The PINK1-Parkin pathway is involved in the regulation of mitochondrial remodeling process. 1905 53

Mitochondrial dysfunction is a common characteristic of all neurodegenerative diseases. However, the cause of this dysfunction remains a mystery. Here, we discuss the potential role of mitochondrial fission and fusion in the onset and progression of neurodegenerative diseases. Specifically, we propose that an imbalance in mitochondrial fission and fusion may underlie both familial and sporadic neurodegenerative disorders. There is substantial evidence that links disruption of the mitochondrial fission and fusion equilibrium, resulting in abnormally long or short mitochondria, to neurodegeneration. First, hereditary mutations in the mitochondrial fusion GTPases optic atrophy-1 and mitofusin-2 cause neuropathies in humans. In addition, recent findings report increased mitochondrial fission in Parkinson's disease (PD) models and induction of mitochondrial fission by two proteins, PTEN-induced kinase 1 and parkin, which are mutant in familial forms of PD. Furthermore, mutant huntingtin, the disease-causing protein in Huntington's disease, alters mitochondrial morphology and dynamics. Rotenone, a pesticide and inducer of PD symptoms, and amyloid-beta peptide, which is causally linked to Alzheimer's disease, initiate mitochondrial fission. Finally, mitochondrial fission is an early event in ischemic stroke and diabetic neuropathies. In sum, a growing body of research suggests that a better understanding of mitochondrial fission and fusion and the regulatory factors involved may lead to improved treatments and cures for neurodegenerative diseases.
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PMID:Impairing the mitochondrial fission and fusion balance: a new mechanism of neurodegeneration. 1907 50


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