Sphingolipid synthesis maintains nuclear membrane integrity and genome stability during cell division

Area of Science:

• Cell Biology
• Molecular Biology
• Genetics

Background:

• Precise regulation of lipid synthesis is vital for cell division and organelle biogenesis.
• Coordination between lipid synthesis and cell cycle progression remains poorly understood.

Purpose of the Study:

• To investigate the role of de novo sphingolipid synthesis in nuclear membrane biogenesis during cell division.
• To determine the consequences of inhibiting sphingolipid synthesis on nuclear morphology and genomic stability.

Main Methods:

• Utilized yeast and human cell models.
• Inhibited serine palmitoyltransferase (SPT) to block de novo sphingolipid synthesis.
• Assessed nuclear membrane integrity, cell cycle progression, and genomic stability.

Main Results:

• De novo sphingolipid synthesis during S and G2 phases is essential for nuclear membrane expansion.
• Sphingolipid precursors (long-chain bases) localize to the nucleus and are part of nuclear membranes.
• SPT inhibition caused nuclear membrane collapse and loss of viability in yeast.
• In human cells, SPT inhibition led to abnormal nuclear morphology and genomic instability, including micronuclei and multipolar mitosis.

Conclusions:

• De novo sphingolipid synthesis is critical for maintaining nuclear integrity during cell division.
• Dysregulation of sphingolipid synthesis can drive disease-associated phenotypes like aberrant nuclear morphology and genomic instability.