Restriction point
From Biocrawler, the free encyclopedia.
The restriction point is a G1 phase checkpoint in animal cells. Cells that progress through this point are committed to enter S phase, where DNA synthesis and replication will occur. If a cell is not ready, or external conditions are not appropriate for the S phase, then the cell may enter G0 phase, a quiescent stage. Lack of growth factors causes some cells to arrest at the restriction point.
Yeast cells contain a similar checkpoint, the start point.
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