Sec14L6 is a phosphoinositide transporter that regulates phosphoinositide homeostasis and biogenesis of lipid droplets.

ABSTRACT: Lipid droplets (LDs) are evolutionarily conserved organelles essential for cellular metabolism. They form and grow at the endoplasmic reticulum (ER), requiring lipid transfer between these compartments, yet the underlying molecular mechanisms remain elusive. We identify Sec14L6, a unique Sec14 family member, as a lipid transporter regulating phosphoinositide (PIP) homeostasis and LD biogenesis, promoting adipogenic differentiation of mesenchymal stem cells. Sec14L6 directly binds the LD biogenesis factor ACSL3, which facilitates the association of Sec14L6 with LD surface. Furthermore, the ER membrane protein PGRMC1 recruits Sec14L6 to the ER. Targeted lipidomics revealed profound PIP dysregulation in Sec14L6-KO cells: LDs accumulated phosphoinositide-4-phosphate (PI4P) and PI(4,5)P₂, while

SUBMITTER: Zhou T 

PROVIDER: S-EPMC12658205 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature