Nuclear transcription factor Y subunit A (IPR001289)

Short name: NFYA

Overlapping homologous superfamilies


Family relationships



Diverse DNA binding proteins are known to bind the CCAAT box, a common cis- acting element found in the promoter and enhancer regions of a large number of genes in eukaryotes. Amongst these proteins is one known as the CCAAT-binding factor (CBF) or nuclear transcription factor Y (NF-Y) [PMID: 1549471]. CBF is a heteromeric transcription factor that consists of two different components both needed for DNA-binding.

The HAP protein complex of yeast binds to the upstream activation site of cytochrome C iso-1 gene (CYC1) as well as other genes involved in mitochondrial electron transport and activates their expression. It also recognises the sequence CCAAT and is structurally and evolutionary related to CBF.

The first subunit of CBF is known as CBF-A or NF-YB in vertebrates, and HAP3 in budding yeast. The second subunit is known as CBF-B or NF-YA in vertebrates and HAP2 in budding yeast. It is a protein of 265 to 350 amino-acid residues which contains a highly conserved region of about 60 residues. This region, called the 'essential core' [PMID: 1899284], seems to consist of two subdomains: an N-terminal subunit-association domain and a C-terminal DNA recognition domain.

This entry represents the NF-YA subunit.

GO terms

Biological Process

GO:0006355 regulation of transcription, DNA-templated

Molecular Function

GO:0003700 DNA-binding transcription factor activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles