Division of Genetics, Brigham and Women's Hospital, Boston, MA 02115, USA.
Cell. 2011 Oct 14;147(2):459-74. doi: 10.1016/j.cell.2011.09.019. Epub 2011 Sep 29.
Cullin-RING ligases (CRLs) represent the largest E3 ubiquitin ligase family in eukaryotes, and the identification of their substrates is critical to understanding regulation of the proteome. Using genetic and pharmacologic Cullin inactivation coupled with genetic (GPS) and proteomic (QUAINT) assays, we have identified hundreds of proteins whose stabilities or ubiquitylation status are regulated by CRLs. Together, these approaches yielded many known CRL substrates as well as a multitude of previously unknown putative substrates. We demonstrate that one substrate, NUSAP1, is an SCF(Cyclin F) substrate during S and G2 phases of the cell cycle and is also degraded in response to DNA damage. This collection of regulated substrates is highly enriched for nodes in protein interaction networks, representing critical connections between regulatory pathways. This demonstrates the broad role of CRL ubiquitylation in all aspects of cellular biology and provides a set of proteins likely to be key indicators of cellular physiology.
Cullin-RING 连接酶 (CRLs) 是真核生物中最大的 E3 泛素连接酶家族，其底物的鉴定对于理解蛋白质组的调控至关重要。我们使用遗传和药理学 Cullin 失活以及遗传 (GPS) 和蛋白质组学 (QUAINT) 测定法，鉴定了数百种蛋白质，其稳定性或泛素化状态受 CRL 调节。这些方法一起产生了许多已知的 CRL 底物以及大量以前未知的假定底物。我们证明，一种底物 NUSAP1 是细胞周期 S 和 G2 期 SCF(Cyclin F) 的底物，并且还响应 DNA 损伤而降解。受调控的这些底物在蛋白质相互作用网络的节点中高度富集，代表了调控途径之间的关键连接。这表明 CRL 泛素化在细胞生物学的各个方面都发挥着广泛的作用，并提供了一组可能是细胞生理学关键指标的蛋白质。
