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Functional Description
Septins are GTPases involved in cytokinesis that assemble early in the cell cycle as a patch at the incipient bud site and form a ring approximate 15 minutes before bud emergence, which transforms into an hour-glass shaped collar of cortical filaments that spans both sides of the mother-bud neck. This collar persists until just before cytokinesis, when it splits into two rings that occupy opposite sides of the neck. The septins at the bud neck serve as a structural scaffold that recruits different components involved in diverse processes at specific stages during the cell cycle. Many proteins bind asymmetrically to the septin collar. The septin assembly is regulated by protein kinases GIN4 and/or CLA4. May act by recruiting MYO1 and HOF1, a protein involved in septation, to the site of cleavage. Septins are also involved in cell morphogenesis, bud site selection, chitin deposition, cell cycle regulation, cell compartmentalization and spore wall formation.