The CCAAT-enhancer binding proteins (C/EBP) are members of the basic region/leucine zipper (bZIP) transcription factors, that bind to the consensus CCAAT sequence in DNA. C/EBPα is expressed in two isoforms: p42 and p30 by ultilizing different translational start codons. The C/EBPα p30 isoform has little to no transactivating activity and acts as an inhibitor. C/EBPα regulates expression of various myeloid-specific genes and is required for myeloid differentiation. C/EBPα has been found to play a key role in adipogenesis, since inhibition of C/EBPα blocks adipocyte differentiation. C/EBPα also regulates cell cycle progression through interactions with cyclin-dependent kinases (CDK) and by inducing the expression of CDK inhibitor p21. Mutations in the C/EBPα gene are associated with the development of acute myeloid leukemia.