TNAP, an Essential Player in Membrane Lipid Rafts of Neuronal Cells

Myriam Ermonval (1) , Florence Baychelier (1) , Caroline Fonta (2)

1 Stratégies antivirales
2 CERCO - Centre de recherche cerveau et cognition

The tissue non-specific alkaline phosphatase (TNAP) is a glycosyl-phosphatidylinositol (GPI) anchored glycoprotein which exists under different forms and is expressed in different tissues. As the other members of the ecto-phosphatase family, TNAP is targeted to membrane lipid rafts. Such micro domains enriched in particular lipids, are involved in cell sorting, are in close contact with the cellular cytoskeleton and play the role of signaling platform. In addition to its location in functional domains, the extracellular orientation of TNAP and the fact this glycoprotein can be shed from plasma membranes, contribute to its different phosphatase activities by acting as a phosphomonoesterase on various soluble substrates (inorganic pyrophosphate -PPi-, pyridoxal phosphate -PLP-, phosphoethanolamine -PEA-), as an ectonucleotidase on nucleotide-phosphate and presumably as a phosphatase able to dephosphorylate phosphoproteins and phospholipids associated to cells or to extra cellular matrix. More and more data accumulate on an involvement of the brain TNAP both in physiological and pathological situations. This review will summarize what is known and expected from the TNAP localization in lipid rafts with a particular emphasis on the role of a neuronal microenvironment on its potential function in the central nervous system.

Mots clés: TNAP activity; Neuronal function; Extra cellular matrix; Protein network; Microenvironment; neuronal function; extra cellular matrix; protein network; microenvironment

Domaines: Sciences du Vivant [q-bio]

Myriam Ermonval, Florence Baychelier, Caroline Fonta. TNAP, an Essential Player in Membrane Lipid Rafts of Neuronal Cells. Caroline Fonta; László Négyessy. Neuronal Tissue-Nonspecific Alkaline Phosphatase (TNAP), 76, Springer Science; Business Media, pp.167-183, 2015, Subcellular Biochemistry, 978-94-017-7196-2 (print); 978-94-017-7197-9 (online). ⟨10.1007/978-94-017-7197-9_9⟩. ⟨hal-02875540⟩