The surface charge of the protein changes the recombination frequency to the cell membrane

PTEN is a protein molecule that traverses the cytoplasm and the cell membrane and has the function of dephosphorylating PIP3 on the cell membrane. PTEN is known as a tumor suppressor gene and it is known that cells become cancerous if PIP3 dephosphorylation on the cell membrane does not function well. Mutation in PTEN and loss of PTEN on the cell membrane also leads to canceration, so clarification of the mechanism of PTEN membrane binding is important in cancer research.

In this study, we studied the mechanism of PTEN membrane binding by looking at various PTEN mutants in living cells using the technique called single molecule imaging. As a result, it was found that when the positive charge of the region where positively charged amino acid of PTEN is accumulated positively charged amino acid is lowered, the binding ability to the cell membrane gradually decreases. Also, we proved through the new analytical method that the probability of returning to the membrane again after single molecule leaves the membrane becomes higher when the charge is in good condition. This study allowed us to approach a part of a novel mechanism for the recombination of PTEN into membranes.

M Yasui, S Matsuoka, M Ueda. “PTEN Hopping on the Cell Membrane Is Regulated via a Positively-Charged C2 Domain” PLoS Comp Biol, 2014