mtm-9 encodes a catalytically inactive myotubularin lipid phosphatase orthologous to human MTMR9 (OMIM:606260) that affects phosphoinositide 3-phosphate localization, and whose mutation blocks endocytosis by the coelomocytes of C. elegans; MTM-9 is believed to function as part of a complex with MTM-6A and it is predominantly localized to the coelomocyte cytoplasm, with some localization to the membrane.
Enables phosphatase binding activity. Involved in pinocytosis and regulation of cell migration. Located in cytosol and plasma membrane. Expressed in several structures, including CAN; PDE; coelomocyte; epithelial cell; and vulva. Used to study centronuclear myopathy. Is an ortholog of human MTMR9 (myotubularin related protein 9).
Mutations in the human myotubularin family of lipid phosphatases, are associated with myotubular myopathy (associated gene, MTM1) and Charcot-Marie-Tooth disease, a group of progressive demyelinating neuropathies that affect the peripheral nerves (associated gene, MTMR2); studies in C. elegans indicate that, elegans mtm-9 together with mtm-6, and possibly other myotubularins, act in the arf-6/ARF6, rme-1/Ehd pathway for endocytosis, suggesting that disruptions in this endocytic pathway may be one of the causes leading to disease.