Myotubularin-related Protein 4, EC=3.1.3.48

MTMR, a member of the myotubularin family, encodes an intracellular protein of 1,195 amino acids, and shares approximately 47% sequence identity with MTMR3, spiking to over 70% identity in the catalytic domain and the double zinc finger (FYVE) motif. PCR analysis detects expression of MTMR4 in all human tissues examined except lung, small intestine, stomach, salivary gland, adrenal gland, and uterus. Subcellular localization of MTMR4 in transfected HeLa cells showed a perinuclear distribution, similar to that seen with MTMR3. MTMR4 dephosphorylates para-nitrophenylphosphate and phosphatidylinositol 3-phosphate.