Oleate activates PLD2 lipase and GEF activity by modulating membrane microdomain dynamics via S-acylation

Area of Science:

• Molecular Biology
• Cell Biology
• Biochemistry

Background:

• Phospholipase D2 (PLD2) is crucial for cellular signaling, membrane dynamics, and cancer progression.
• Oleate (OA) activates PLD2, enhancing triple-negative breast cancer (TNBC) cell migration, but mechanisms are unclear.

Purpose of the Study:

• To elucidate the molecular mechanisms by which OA modulates PLD2 activity and promotes TNBC cell migration.

Main Methods:

• Confocal microscopy
• Lipid raft isolation
• S-acylation assays
• Site-directed mutagenesis

Main Results:

• OA enhances PLD2 S-acylation at Cys223/Cys224, disrupting lipid raft localization and increasing colocalization with PIP2 microdomains.
• PLD2 acts as a guanine nucleotide exchange factor (GEF) for Cdc42, with activity regulated by OA-dependent S-acylation and lipid raft dynamics.
• Disruption of S-acylation sites or lipid rafts abolished PLD2-mediated Cdc42 activation and cell protrusion formation.

Conclusions:

• OA regulates PLD2 activity via S-acylation and membrane microdomain reorganization.
• This mechanism provides novel insights into PLD2 regulation in cell migration and signaling, particularly in TNBC.