EC Number   |
General Information |
Reference |
|---|
   3.1.3.64 | malfunction |
activity of SidP rescues the growth phenotype of a yeast strain defective in PI(3)P phosphatase activity |
732112 |
| 3.1.3.64 | malfunction |
four of the fifteen PI3P phosphatases present in mammals have been linked to serious human diseases. MTM1 defects cause X-linked myotubular myopathy also known as centronuclear myopathy, a severe congenital disorder affecting the physiology of skeletal muscle fibers and characterized by centrally localized nuclei and hypotonia. More than two hundred different mutations, truncations and missenses, in MTM1 are reported in XLMTM patients that result in loss or decrease of MTM1 level. MTMR2 and MTMR13 are mutated in two forms of Charcot-Marie-Tooth type 4B, CMT type 4, disease, an autosomal recessive disorder of the peripheral nervous system characterized by nerve demyelination and myelin outfoldings. CMT type 4B1 is caused by missense or deletion mutations in MTMR2 gene that result in MTMR2 loss of function. In addition to CMT4B1, one patient manifests azoospermia suggesting that MTMR2 also plays a role in testis |
715016 |
| 3.1.3.64 | malfunction |
inactivating mtm-1, blocks phagosome maturation |
732666 |
| 3.1.3.64 | malfunction |
inactivation or knockdown of MTMR3 initiates autophagosome formation, and overexpression of wild-type MTMR3 led to significantly smaller nascent autophagosomes and a net reduction in autophagic activity |
716970 |
| 3.1.3.64 | malfunction |
knockdown of MTMR2 reduces excitatory synapse number and suppresses synaptic transmission. Mutations in the MTMR2 gene in Schwann cells lead to a severe demyelinating peripheral neuropathy known as Charcot-Marie-Tooth disease type 4B1. Knockdown of MTMR2 in cultured neurons markedly reduces excitatory synapse density and function. It causes a marked reduction in the frequency, but not amplitude, of miniature EPSCs. This effect is rescued by wild-type MTMR2 but not by a mutant MTMR2 lacking PSD-95 binding or 3-phosphatase activity. MTMR2 knockdown leads to a decrease in the intensity of EEA1-positive early endosomes in dendrites but increases the intensity in the cell body region. Moreover, MTMR2 suppression promotes endocytosis, but not recycling, of the GluR2 subunit of AMPA receptors, which is an endosomal cargo. MTMR2 knockdown reduces spine density by suppressing spine maintenance, and not formation |
715992 |
| 3.1.3.64 | malfunction |
MTMR2-deficient mice develop CMT4B1-like neuropathy and azoospermia. MTMR13-deficient mice manifest myelin outfoldings in peripheral nerves. Jumpy or MTMR14-/- mice display muscle weakness and fatigue similar to patients with centronuclear myopathy |
715016 |
| 3.1.3.64 | malfunction |
reduction of MTMR6 accelerates the transport of vesicular stomatitis virus glycoprotein in which Rab1B is involved. Furthermore, reduction of MTMR6 or Rab1B inhibits the formation of the tubular omegasome that is induced by overexpression of DFCP1 in autophagy |
732086 |
| 3.1.3.64 | metabolism |
autophagy initiation depends on the balance between PI 3-kinase and PI 3-phosphatase activity |
716970 |
| 3.1.3.64 | metabolism |
autophagy initiation is strictly dependent on phosphatidylinositol 3-phosphate synthesis. PI3P production is under tight control of PI3Kinase, hVps34, in complex with Beclin-1. PI3P metabolism involved in autophagy initiation is further regulated by the PI3P phosphatases Jumpy and MTMR3, and other PI3P phosphatases might be involved in this process |
715016 |
| 3.1.3.64 | more |
PI3P is a substrate for PIP5-kinase, Fab1, also named PIKfyve, an enzyme that generates phosphoinositide 1-phosphatidyl-1D-myo-inositol 3,5-diphosphate |
715016 |
