PRELID1 (PRELI domain containing 1) functions as a mitochondrial lipid transfer protein that regulates phospholipid transport and cellular stress responses. The protein forms a heterodimeric complex with TRIAP1 to facilitate phosphatidic acid (PA) transport across the mitochondrial intermembrane space, providing PA for cardiolipin synthesis in the inner membrane 1. PRELID1 contains both a PRELI/MSF1 domain and a LEA (late embryogenesis abundant) domain, with the LEA domain conferring protection against oxidative stress 2. Loss of PRELID1 function impairs cellular stress signaling, including unfolded protein response and mTORC1 signaling pathways, independent of its effects on cardiolipin synthesis 3. The protein undergoes proteolytic processing by the mitochondrial protease YME1L1, and defects in this processing are associated with metabolic disorders 4. In disease contexts, PRELID1 expression is dysregulated across multiple cancer types through alternative polyadenylation mechanisms, affecting mitochondrial ROS production and serving as a prognostic marker 5. High PRELID1 expression promotes epithelial-mesenchymal transition in gastric cancer cells via PI3K/AKT/mTOR pathway activation and correlates with poor patient outcomes 6. Additionally, PRELID1 has been identified as potentially causally related to blood pressure regulation through genome-wide Mendelian randomization studies 7.