PI(3)P and DFCP1 regulate the biogenesis of lipid droplets.

Ivan Lukmantara, Fang Chen, Hoi Yin Mak, Armella Zadoorian, Ximing Du, Fanqian Nicole Xiao, Dougall MacMurray Norris, Elvis Pandzic, Renee Whan, Qing Zhong, Hongyuan Yang

Molecular biology of the cell 2022 Nov 18

filter terms:

The biogenesis of lipid droplets (LDs), key organelles for cellular lipid storage and homeostasis, remains poorly understood. Seipin is essential to normal LD biogenesis but exactly how it regulates LD initiation remains to be elucidated. Our previous results suggested that seipin may bind anionic phospholipids such as PI(3)P. Here, we investigate whether PI(3)P is functionally linked to seipin and whether PI(3)P can also impact LD biogenesis. In seipin-deficient cells, there were enlarged PI(3)P puncta where its effector, DFCP1, also appeared to congregate. Reducing cellular PI(3)P partially rescued the defective LD initiation caused by seipin deficiency. Increasing PI(3)P impeded the lipidation of nascent LDs. We further demonstrated that DFCP1 localized to LDs and facilitated the efficient lipidation of nascent LDs. However, the normal function and localization of DFCP1 were disrupted when cellular PI(3)P homeostasis was perturbed. Our results thus identify PI(3)P as a novel regulator of LD initiation and suggest that PI(3)P may impact the biogenesis of LDs through DFCP1.

Citation

Ivan Lukmantara, Fang Chen, Hoi Yin Mak, Armella Zadoorian, Ximing Du, Fanqian Nicole Xiao, Dougall MacMurray Norris, Elvis Pandzic, Renee Whan, Qing Zhong, Hongyuan Yang. PI(3)P and DFCP1 regulate the biogenesis of lipid droplets. Molecular biology of the cell. 2022 Nov 18;33(14):ar131