Septin structure and filament assembly

Area of Science:

• Cell Biology
• Structural Biology
• Biochemistry

Background:

• Septins are apolar filaments, considered key cytoskeletal components alongside intermediate filaments, microtubules, and actin.
• Septin filaments assemble from multiple monomers, with human septins typically forming structures from three or four distinct subunits.
• The guanosine triphosphate (GTP)-binding domain is central to filament stability, but structural details of inter-domain interfaces remain incompletely understood.

Purpose of the Study:

• To review significant advancements in septin structural biology over the past decade.
• To elucidate the structural basis of septin filament self-assembly.
• To clarify existing misconceptions regarding septin structures and functions.

Main Methods:

• Compilation and analysis of determined septin structures.
• Focus on structural data derived primarily from human septins.
• Comparative analysis of structural interfaces within GTP-binding domains.

Main Results:

• Summarizes progress in understanding septin filament formation.
• Highlights key structural features of determined septin complexes.
• Identifies previously unremarked details in septin structures and filament organization.

Conclusions:

• Recent structural studies have significantly advanced the understanding of septin filament assembly.
• Detailed analysis of GTP-binding domain interfaces is crucial for comprehending septin polymerization.
• This review consolidates current knowledge and addresses misconceptions in the field.