在对DNA损伤和复制阻滞作出反应时，通过控制关键的细胞周期调节器，细胞周期进程停止。该基因编码的蛋白质是一种细胞周期检查点调节因子和假定的肿瘤抑制因子。它包含一个叉头相关蛋白相互作用域，在对DNA损伤作出反应时对激活至关重要，并在对复制阻滞和DNA损伤作出反应时迅速磷酸化。当被激活时，编码蛋白被认为能抑制CDC25C磷酸酶，防止进入有丝分裂，并已被证明能稳定肿瘤抑制蛋白p53，导致细胞周期在g1停滞。此外，这种蛋白与BRCA1相互作用并磷酸化，使BRCA1在DNA损伤后恢复生存。这种基因的突变与李夫琅梅尼综合征有关，李夫琅梅尼综合征是一种高度渗透性的家族性癌症表型，通常与TP53的遗传突变有关。而且，这种基因的突变被认为是导致肉瘤、乳腺癌和脑肿瘤的一种倾向。这种核蛋白是丝氨酸/苏氨酸蛋白激酶CDS1亚家族的成员。一些转录变体编码不同的亚型已被发现的这个基因。
In response to DNA damage and replication blocks, cell cycle progression is halted through the control of critical cell cycle regulators. The protein encoded by this gene is a cell cycle checkpoint regulator and putative tumor suppressor. It contains a forkhead-associated protein interaction domain essential for activation in response to DNA damage and is rapidly phosphorylated in response to replication blocks and DNA damage. When activated, the encoded protein is known to inhibit CDC25C phosphatase, preventing entry into mitosis, and has been shown to stabilize the tumor suppressor protein p53, leading to cell cycle arrest in G1. In addition, this protein interacts with and phosphorylates BRCA1, allowing BRCA1 to restore survival after DNA damage. Mutations in this gene have been linked with Li-Fraumeni syndrome, a highly penetrant familial cancer phenotype usually associated with inherited mutations in TP53. Also, mutations in this gene are thought to confer a predisposition to sarcomas, breast cancer, and brain tumors. This nuclear protein is a member of the CDS1 subfamily of serine/threonine protein kinases. Several transcript variants encoding different isoforms have been found for this gene.