Related Experiment Video
Updated: May 27, 2026

Purification and Quality Control of Recombinant Septin Complexes for Cell-Free Reconstitution
Published on: June 23, 2022
SEPT9 occupies the terminal positions in septin octamers and mediates polymerization-dependent functions in
Moshe S Kim1, Carol D Froese, Mathew P Estey
1Program in Cell Biology, Hospital for Sick Children, University of Toronto, Toronto, Ontario M5G 1X8, Canada.
Abstract:
Septins are filamentous guanosine triphosphatase-binding proteins that are required for cytokinesis in a wide range of organisms from yeast to man. Several septins, including SEPT9, have been found to be altered in cancers, but their roles in malignancy and cytokinesis remain unclear. It is known that they assemble into rod-shaped oligomeric complexes that join end-on-end to form filaments, but whether SEPT9 incorporates into these complexes and how it does so are unanswered questions. We used tandem affinity purification of mammalian septin complexes to show that SEPT9 occupies a terminal position in an octameric septin complex. A mutant SEPT9, which cannot self-associate, disrupted septin filament formation and resulted in late abscission defects during cytokinesis but did not affect septin-dependent steps earlier in mitosis. These data suggest that mammalian SEPT9 holds a terminal position in the septin octamers, mediating abscission-specific polymerization during cytokinesis.
More Related Videos
Related Concept Videos
Septins
Role of Septins
Cellular Functions of Septins
Recent studies have revealed the multifaceted roles of septins in various cellular processes such as cytokinesis, ciliogenesis, and neurogenesis. Septins act as scaffolds and...
The Contractile Ring
A small GTPase, RhoA, controls the function and assembly of the contractile ring. RhoA belongs to the Ras superfamily of proteins. The activation of formins by RhoA promotes...
Tail-anchoring of Proteins in the ER Membrane
Separation of Sister Chromatids
At the onset of anaphase, separase, a proteolytic enzyme, is...
Role of Microtubules in Cell Wall Deposition

