Function
Transmembrane protein that binds to and facilitates the assembly of lysosomal proton-transporting V-type ATPase (v-ATPase), resulting in enhanced lysosomal acidification and trafficking. By bringing the v-ATPase accessory protein ATP6AP2 and the v-ATPase subunit ATP6V0D1 together, allows v-ATPase complex formation and activation. TMEM9-controlled vesicular acidification induces hyperactivation of Wnt/beta-catenin signaling, involved in development, tissue homeostasis and tissue regeneration, through lysosomal degradation of adenomatous polyposis coli/APC. In the liver, involved in hepatic regeneration.
Tissue Specificity
Highly expressed in adrenal gland, thyroid gland, testis, ovary and prostate. Moderate expression in trachea, spinal cord, stomach, colon, small intestine and spleen. Low expression in bone marrow, lymph node, thymus and peripheral blood lymphocytes. Expr
