It takes two to tango

Abstract

PROPPINs are a family of PtdIns3P and PtdIns(3,5)P₂-binding proteins. The crystal structure now unravels the presence of two distinct phosphoinositide-binding sites at the circumference of the seven bladed β-propeller. Mutagenesis analysis of the binding sites shows that both are required for normal membrane association and autophagic activities. We identified a set of evolutionarily conserved basic and polar residues within both binding pockets, which are crucial for phosphoinositide binding. We expect that membrane association of PROPPINs is further stabilized by membrane insertions and interactions with other proteins.

Keywords: :

• autophagy
• protein-lipid interactions
• X-ray crystallography
• S. cerevisiae

This article refers to:

Acknowledgments

This work was funded by the DFG through the SFB860 (to M.T. and K.K.).