Fission yeast cells divide precisely at their middle. Once the cell reaches a critical size, the scaffolding protein anillin/Mid1p accumulates at the cell’s equator, where it anchors to the plasma membrane to form “nodes”, the precursors for actomyosin contractile ring (ACR) assembly (Upper Figure 4). These nodes then coalesce and recruit the necessary contractile ring machinery. Following its assembly, the ring constricts, as its name implies, driving ingression of the plasma membrane while simultaneously directing the deposition of septum material. This newly synthesized cell wall is ultimately remodeled to generate the two daughter cells (Lower Figure 4).
Figure 4: Finding the Middle and Building the Wall: Cytokinesis in Fission Yeast.
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