A proposed model for the role of Ubc9 in AML with C/EBPα mutation. Model depicting how C/EBPαp30 enhances C/EBPαp42 sumoylation via up-regulation of Ubc9 and blocks the transcription and differentiation potential of C/EBPαp42, and how Ubc9 siRNA overcomes the C/EBPαp30-mediated block of transcription and differentiation potential of C/EBPαp42.