CREB1, also known as cAMP responsive element binding protein 1, is a protein that in humans is encoded by the CREB1 gene. It is mapped to 2q33.3. This protein binds the cAMP response element, a DNA nucleotide sequence present in many viral and cellular promoters. The binding of CREB1 stimulates transcription. This protein is a CREB transcription factor that is a member of the leucine zipper family of DNA-binding proteins. This protein binds as a homodimer to the cAMP-responsive element, an octameric palindrome. The protein is phosphorylated by several protein kinases, and induces transcription of genes in response to hormonal stimulation of the cAMP pathway.