Figure 1.

PTEN protein structure. (A) The canonical PTEN isoform consists of 403 amino acids structured in five functional domains: a phosphatidylInositol-4,5-bisphosphate (PIP2)-binding domain (PBD), a phosphatase domain (catalytic core), a C2 lipid membrane-binding domain, a C-terminal tail domain (which contains phosphorylation sites implicated in the regulation of PTEN activity/stability and localization) and a PDZ protein–protein interactions domain. (B) PTEN has four translational variants (PTEN-L, -M, -N and -O) which contain an additional N-terminus and differ in functions and sub-cellular localization. Translation begins from a translation site upstream the canonical initiation sequence and resulting in N-terminal extensions for each of the variants.