CCAAT binding transcription factor (CBF) refers to a class of regulatory proteins that bind to specific DNA sequences called the CCAAT box, which are commonly found in the promoter region of a multitude of genes. CBF plays a crucial role in gene expression regulation by interacting with other transcription factors and affecting the initiation of transcription.
CBF is a heterotrimeric protein complex composed of three subunits. The alpha subunit, also known as NF-YA, is responsible for DNA binding and recognition of the CCAAT box sequence. The beta subunit, or NF-YB, aids in stabilizing the complex, while the gamma subunit, or NF-YC, mediates the interaction between the alpha and beta subunits.
Once bound to the CCAAT box, CBF recruits other transcription factors and coactivators to form a larger transcriptional complex. This complex facilitates the binding of RNA polymerase II to the gene promoter, initiating transcription and eventually leading to the production of messenger RNA (mRNA) transcripts.
CBF plays a vital role in various biological processes, including cell cycle regulation, differentiation, and development. It controls the expression of numerous genes involved in essential functions such as metabolism, immune response, and cellular proliferation. Dysregulation or mutations in CBF or its target genes can lead to various diseases, including cancer, autoimmune disorders, and developmental abnormalities.
In summary, CCAAT binding transcription factor is a regulatory protein complex that binds to the CCAAT box in gene promoters, controlling gene expression by facilitating the initiation of transcription and coordinating the activity of multiple transcription factors.
