Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary neuropathies are classified into Charcot-Marie-Tooth disease (CMT), familial amyloid polyneuropathy (FAP), hereditary motor neuropathies (HMN) and hereditary sensory (and autonomic) neuropathies (HSAN). CMTs are furthermore classified into demyelinating neuropathies (CMT1), axonal neuropathies (CMT2) and intermediate form. Duplication of PMP22 (CMT1A) accounts for about 70% of CMT1 and MFN2 mutations account for 25% of CMT2. Genes involved in phosphoinositide regulation cause CMT4; MTMR2 mutation in CMT 4B1 and MTMR13/SBF2 mutation in CMT4B2. In addition to these genes, FIG4, which is a causative gene of pale tremor mouse, is newly identified as a gene for CMT4J. MFN2 and GDAP1 cause CMT2 or CMT4. These genes regulate mitochondrial fusion and fission. Altered axonal mitochondrial transport is suggested as the pathogenesis of the CMT. In animal model with pmp22 duplication, ascorbic acid seems to be effective to prevent disease progression. Nationwide trial of ascorbic acid therapy for CMT1A is now ongoing by the intractable neuropathy study group. Curcumin treatment educes apoptosis of cells that express PMP22 point mutation and partially mitigates the severe neuropathy phenotype of Trembler-J mouse model in a dose-dependent manner. Curcumin treatment may have a potential therapeutic role in CMT with PMP22 point mutation in humans. The high throughput system of diagnosis for CMT has been developed by employing a resequencing array system.
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PMID:[Hereditary neuropathy: recent advance]. 1919 50

We previously reported that autosomal recessive demyelinating Charcot-Marie-Tooth (CMT) type 4B1 neuropathy with myelin outfoldings is caused by loss of MTMR2 (Myotubularin-related 2) in humans, and we created a faithful mouse model of the disease. MTMR2 dephosphorylates both PtdIns3P and PtdIns(3,5)P(2), thereby regulating membrane trafficking. However, the function of MTMR2 and the role of the MTMR2 phospholipid phosphatase activity in vivo in the nerve still remain to be assessed. Mutations in FIG4 are associated with CMT4J neuropathy characterized by both axonal and myelin damage in peripheral nerve. Loss of Fig4 function in the plt (pale tremor) mouse produces spongiform degeneration of the brain and peripheral neuropathy. Since FIG4 has a role in generation of PtdIns(3,5)P(2) and MTMR2 catalyzes its dephosphorylation, these two phosphatases might be expected to have opposite effects in the control of PtdIns(3,5)P(2) homeostasis and their mutations might have compensatory effects in vivo. To explore the role of the MTMR2 phospholipid phosphatase activity in vivo, we generated and characterized the Mtmr2/Fig4 double null mutant mice. Here we provide strong evidence that Mtmr2 and Fig4 functionally interact in both Schwann cells and neurons, and we reveal for the first time a role of Mtmr2 in neurons in vivo. Our results also suggest that imbalance of PtdIns(3,5)P(2) is at the basis of altered longitudinal myelin growth and of myelin outfolding formation. Reduction of Fig4 by null heterozygosity and downregulation of PIKfyve both rescue Mtmr2-null myelin outfoldings in vivo and in vitro.
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PMID:Genetic interaction between MTMR2 and FIG4 phospholipid phosphatases involved in Charcot-Marie-Tooth neuropathies. 2202 65