TRIB1 is a component of the COP1 ubiquitin ligase complex and plays a pivotal role in leukemogenesis and differentiation blockade by promoting proteolysis of CCAAT/enhancer binding proteins (C/EBPα and C/EBPβ), which are crucial inducers of differentiation in AML. The gene discussed is COP1; the disease is acute myeloid leukemia.