PI is phosphorylated to PI5P by PIKFYVE at the late endosome membrane

At the late endosome membrane, the PAS complex, consisting of FYVE finger-containing phosphoinositide kinase (PIKFYVE), yeast VAC14 homologue (VAC14), and polyphosphoinositide phosphatase aka SAC3 (FIG4), binds to the membrane via PIKFYVE's FYVE finger. The PIKFYVE kinase component phosphorylates phosphatidylinositol (PI) to phosphatidylinositol 5-phosphate (PI5P) (Sbrissa et al. 1999, Sbrissa et al. 2002). The PAS complex is present in the cytosol and is recruited to the membrane.

在晚期内质网膜上，由含FYVE指的磷脂酰肌醇激酶（PIKFYVE）、酵母VAC14同源物（VAC14）以及多磷酸肌醇磷脂磷酸酶亦称SAC3（FIG4）组成的PAS复合物，通过PIKFYVE的FYVE指与膜结合。PIKFYVE激酶成分将磷脂酰肌醇（PI）磷酸化为磷脂酰肌醇5-磷酸（PI5P）（Sbrissa等，1999年，Sbrissa等，2002年）。PAS复合物存在于细胞质中，并被招募至膜上。