Cellular phosphatidic acid sensor, ?-synuclein N-terminal domain, detects endogenous phosphatidic acid in macrophagic phagosomes and neuronal growth cones.

ABSTRACT: Phosphatidic acid (PA) is the simplest phospholipid and is involved in the regulation of various cellular events. Recently, we developed a new PA sensor, the N-terminal region of ?-synuclein (?-Syn-N). However, whether ?-Syn-N can sense physiologically produced, endogenous PA remains unclear. We first established an inactive PA sensor (?-Syn-N-KQ) as a negative control by replacing all eleven lysine residues with glutamine residues. Using confocal microscopy, we next verified that ?-Syn-N, but not ?-Syn-N-KQ, detected PA in macrophagic phagosomes in which PA is known to be enriched, further indicating that ?-Syn-N can be used as a reliable PA sensor in cells. Finally, because PA generated during neuronal differentiation is critical for neurite outgrowth, we investigated the subcellular distribution of PA using ?-Syn-N. We found that ?-Syn-N, but not ?-Syn-N-KQ, accumulated at the peripheral regions (close to the plasma membrane) of neuronal growth cones. Experiments using a phospholipase D (PLD) inhibitor strongly suggested that PA in the peripheral regions of the growth cone was primarily produced by PLD. Our findings provide a reliable sensor of endogenous PA and novel insights into the distribution of PA during neuronal differentiation.

SUBMITTER: Yamada H 

PROVIDER: S-EPMC7261706 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature