Phosphatidylinositol-3-phosphate phosphatase MTMR7

MTMR7 is a lipid phosphatase that catalyzes dephosphorylation of phosphatidylinositol 3-phosphate (PtdIns(3)P) and inositol 1,3-bisphosphate, thereby regulating phosphoinositide signaling (UniProt: Q9Y216). The protein is a 660-amino acid enzyme with a molecular mass of approximately 75.8 kDa.

MTMR7 participates in cellular lipid metabolism and endosomal membrane homeostasis through its phosphatase activity. While no diseases are explicitly listed in UniProt for this protein, it may have relevance to conditions affecting membrane trafficking and lipid signaling.

In Alzheimer's Disease, MTMR7 is consistently downregulated in post-mortem AD brain tissue relative to age-matched controls (Chaparral AD proteomics). Across subcellular fractions analyzed in a TMT-labeled proteomics experiment, the protein showed a mean log2 fold-change of −0.66, suggesting a moderate decrease. This downregulation may reflect altered phosphoinositide signaling or endosomal dysfunction in the AD brain.