MTMR6 is a lipid phosphatase that specifically dephosphorylates phosphatidylinositol 3-phosphate (PI3P) and phosphatidylinositol 3,5-bisphosphate at the D-3 position, generating phosphatidylinositol and phosphatidylinositol 5-phosphate 1. The enzyme exhibits high binding affinity for PI3P, PI(3,5)P2, and other phospholipids including phosphatidic acid and phosphatidylserine 1. MTMR6 functions through formation of heteromeric complexes, particularly with the catalytically inactive MTMR9, which stabilizes both proteins and increases MTMR6 phosphatase activity up to 84-fold 1. The protein negatively regulates Ca2+-activated K+ channel KCa3.1 activity in CD4+ T-cells by depleting intracellular PI3P levels, requiring both coiled-coil and PH/GRAM domains for proper localization and channel inhibition 2. MTMR6 plays crucial roles in cellular processes including autophagy regulation by maintaining autophagic flux 3, DNA damage-induced apoptosis suppression when complexed with MTMR9 1, and immune regulation through TLR2-mediated pathways in macrophages during Leishmania infection 4. Clinically, MTMR6 represents a potential therapeutic target for visceral leishmaniasis, as its silencing reduces parasite load and enhances protective immune responses 5. The protein has also been implicated in pancreatic cancer susceptibility and shows altered expression patterns in smoking-related brain changes 67.