This domain family is found in eukaryotes, and is typically between 192 and 219 amino acids in length. The family is found in association with Pfam:PF05076. There is a conserved HGRHFT sequence motif. This family is the C terminal domain of the Suppressor of Fused protein (Su(fu)). Su(fu) is a repressor of the Gli and Ci transcription factors of the Hedgehog signalling cascade. It functions by binding these proteins and preventing their translocation to the nucleus. The C terminal domain is only found in eukaryotic Su(fu) proteins; it is not present in bacterial homologues. The C terminal domain binds to the N terminal of Gli/Ci while the N terminal of Su(fu) binds to the C terminal of Gli/Ci. This dual binding mechanism is likely an evolutionary advancement in this signalling cascade which is not present in bacterial homologues.

1: Suppressor of fused regulates Gli activity through a dual binding mechanism. Merchant M, Vajdos FF, Ultsch M, Maun HR, Wendt U, Cannon J, Desmarais W, Lazarus RA, de Vos AM, de Sauvage FJ; Mol Cell Biol. 2004;24:8627-8641. PMID:15367681