西亚试剂：：SUMO1 modification of PTEN regulates

Jian Huang,  Jie Yan,  Jian Zhang,  Shiguo Zhu,  Yanli Wang,  Ting Shi,  Changhong Zhu,  Cheng Chen, Xin Liu,  Jinke Cheng,  Tomas Mustelin,  Gen-Sheng Feng,  Guoqiang Chen  & Jianxiu Yu

The membrane association of the tumour suppressor phosphatase and tensin homologue (PTEN) is required to oppose the phosphatidylinositol-3-kinase/AKT pathway by dephosphorylation of phosphatidylinositol-3,4,5-triphosphate (PIP3). How cytosolic PTEN interacts with its main substrate, PIP3, localized at the inner face of plasma membrane remains unclear. Here we show that PTEN is covalently modified by SUMO1 at both K266 and K254 sites in the C2 domain of PTEN. SUMO1 modification at K266 located in the CBR3 loop, which has a central role in PTEN membrane association, mainly facilitates cooperative binding of PTEN to the plasma membrane by electrostatic interactions. This results in the downregulation of the phosphatidylinositol-3 kinase/AKT pathway and consequently, suppression of anchorage-independent cell proliferation and tumour growth in vivo. Our data demonstrate a molecular mechanism whereby SUMO1 modification is required for PTEN tumour suppressor function by controlling PTEN membrane association and regulation of the phosphatidylinositol-3 kinase/AKT pathway.