Cryo-EM structure of TMEM164 reveals distinct phospholipid remodeling mechanisms with anti-ferroptotic potential

Area of Science:

• Cell Biology
• Biochemistry
• Structural Biology

Background:

• Cell membrane phospholipids play crucial roles in cell regulation and structure.
• The precise mechanisms by which lipid remodeling influences cell fate are not fully understood.

Purpose of the Study:

• To elucidate the structure and function of TMEM164, an identified anti-ferroptotic factor.
• To investigate how TMEM164-mediated lipid remodeling affects ferroptosis.

Main Methods:

• Genome-wide CRISPR screening to identify TMEM164.
• Cryo-electron microscopy to determine TMEM164 structure.
• Biochemical assays and mutagenesis to validate catalytic residues and function.
• Virtual screening and rational design to identify TMEM164 inhibitors.

Main Results:

• Determined the cryo-electron microscopy structure of TMEM164, revealing a dimeric architecture with a metal ion catalytic center.
• Identified a phospholipid substrate in a polyunsaturated fatty acyl (PUFA)-C123 intermediate state.
• Demonstrated that TMEM164 loss or gain of function alters specific phospholipid levels (PUFA-ePE, C16/18:1-ePE), conferring resistance to ferroptosis.
• Validated key residues in the catalytic and chelation centers (C123, E106, Y177, H181).
• Identified Montelukast S-enantiomer as a high-affinity inhibitor of TMEM164.

Conclusions:

• TMEM164 functions as a membrane lipid remodeler that regulates cell fate by controlling ferroptosis.
• The study highlights the integration of multi-scale platforms for mechanistic and functional investigations.
• TMEM164 represents a potential therapeutic target for modulating ferroptosis.