Cyclin-dependent kinase 1–Cyclin B complex (CDK1–CCNB) (CDK1–CCNB)

The Cyclin-dependent kinase 1–Cyclin B complex, historically known as the Maturation-Promoting Factor (MPF), is a master regulator of the eukaryotic cell cycle, specifically governing the transition from G2 phase into mitosis (StatPearls, PMID: 30855847). The complex consists of the catalytic subunit CDK1 and its regulatory partner, Cyclin B (primarily Cyclin B1), which together phosphorylate a wide array of substrates necessary for nuclear envelope breakdown, spindle assembly, and chromosome condensation (UniProt, P06493; UniProt, P14635). In many human cancers, the CDK1–Cyclin B complex is frequently overexpressed or hyperactivated, driving uncontrolled cell division and contributing to genomic instability (PubMed, 26003166). Consequently, it has been a significant target for oncology drug development, with several small-molecule inhibitors like Dinaciclib and Alvocidib designed to compete with ATP binding at the CDK1 active site (PubChem, CID 46926350). While early pan-CDK inhibitors faced challenges due to narrow therapeutic windows and off-target toxicities such as neutropenia, newer generations of inhibitors are being evaluated in combination therapies to improve efficacy (PubMed, 30634354). Monitoring biomarkers such as Cyclin B1 expression and phospho-histone H3 levels is often employed to assess the pharmacodynamic impact of these therapeutic agents in clinical settings (PubMed, 22496214).

Other names

Maturation-promoting factorMPFM-phase promoting factorCDC2–Cyclin B complexCDK1–CCNB1 complex

ATP-competitive inhibition of the CDK1 catalytic subunit, preventing the phosphorylation of mitotic substrates and inducing cell cycle arrest at the G2/M phase.