In molecular biology, the CFC domain (Cripto_Frl-1_Cryptic domain) is a protein domain found at the

C-terminus The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...

of a number of

proteins Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

including Cripto (or teratocarcinoma-derived growth factor). It is structurally similar to the C-terminal extracellular portions of

Jagged 1 Jagged1 (''JAG1'') is one of five cell surface proteins (Ligand (biochemistry), ligands) that interact with four receptors in the mammalian Notch signaling pathway. The Notch Signaling Pathway is a highly conserved pathway that functions to establi ...

and

Jagged 2 Jagged-2 is a protein that in humans is encoded by the ''JAG2'' gene. Function The Notch signaling pathway is an intercellular signaling mechanism that is essential for proper embryonic development. Members of the Notch gene family encode trans ...

. CFC is approx 40-residues long, compacted by three internal disulphide bridges, and binds

Alk4 Activin receptor type-1B is a protein that in humans is encoded by the ''ACVR1B'' gene. ACVR1B or ALK-4 acts as a transducer of activin or activin-like ligands (e.g., inhibin) signals. Activin binds to either ACVR2A or ACVR2B and then forms a co ...

via a hydrophobic patch. CFC is structurally

homologous Homology may refer to: Sciences Biology *Homology (biology), any characteristic of biological organisms that is derived from a common ancestor *Sequence homology, biological homology between DNA, RNA, or protein sequences * Homologous chrom ...

to the VWFC-like domain. The CFC domain appears to play a crucial role in the tumourigenic activity of Cripto proteins, as it is through the CFC domain that Cripto interferes with the onco-suppressive activity of

Activins Activin and inhibin are two closely related protein complexes that have almost directly opposite biological effects. Identified in 1986, activin enhances FSH biosynthesis and secretion, and participates in the regulation of the menstrual cy ...

, either by blocking the Activin receptor ALK4 or by antagonising proteins of the TGF-beta family.

References

{{InterPro content, IPR019011 Protein domains