Graduate School of Frontier Biosciences, Osaka University

Japanese

Single-molecule imaging of PI(4,5)P2 and PTEN in vitro reveals a positive feedback mechanism for PTEN membrane binding

Journal Commun Biol 3, 92 (2020)
Authors Yoshioka D (1, 2, 3), Fukushima S (1, 2, 3), Koteishi H (2), Okuno D (2), Ide T (4), Matsuoka S (1, 2, 3), Ueda M (1, 2, 3)
  1. Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka, 565-0043, Japan.
  2. Center for Biosystems Dynamics Research (BDR), RIKEN, Suita, Osaka, 565-0874, Japan.
  3. Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan.
  4. Graduate School of Natural Science and Technology, Okayama University, Okayama-shi, Okayama, 700-8530, Japan.
Title Single-molecule imaging of PI(4,5)P2 and PTEN in vitro reveals a positive feedback mechanism for PTEN membrane binding
PubMed 32111929
Laboratory Laboratory of Single Molecule Biology 〈Prof. Ueda〉
Abstract PTEN, a 3-phosphatase of phosphoinositide, regulates asymmetric PI(3,4,5)P3 signaling for the anterior-posterior polarization and migration of motile cells. PTEN acts through posterior localization on the plasma membrane, but the mechanism for this accumulation is poorly understood. Here we developed an in vitro single-molecule imaging assay with various lipid compositions and use it to demonstrate that the enzymatic product, PI(4,5)P2, stabilizes PTEN's membrane-binding. The dissociation kinetics and lateral mobility of PTEN depended on the PI(4,5)P2 density on artificial lipid bilayers. The basic residues of PTEN were responsible for electrostatic interactions with anionic PI(4,5)P2 and thus the PI(4,5)P2-dependent stabilization. Single-molecule imaging in living Dictyostelium cells revealed that these interactions were indispensable for the stabilization in vivo, which enabled efficient cell migration by accumulating PTEN posteriorly to restrict PI(3,4,5)P3 distribution to the anterior. These results suggest that PI(4,5)P2-mediated positive feedback and PTEN-induced PI(4,5)P2 clustering may be important for anterior-posterior polarization.