Abstract 1421 Mapping dynamic ER contacts using PIPERs reveals PI3P to PI4P transition during endosome maturation

Endocytic processes are connected to cell growth, signaling, and metabolism, crucial for health and disease. Endosomes undergo extensive changes as they mature. Changes in phosphoinositide (PIP) and specific proteins on the cytosolic surface of individual endosomes control the direction of endosome traffic. In addition, endosomes mature while forming contacts with the endoplasmic reticulum (ER). Although ER-endosome contacts are crucial for endosome functions, it is challenging to track ER contacts with endosomes that constantly change and traffic during the maturation process.