The FF domain is a 60 amino acid residue phosphopeptide-binding module
containing two conserved phenylalanine (FF) residues that give name to the
domain. While protein-interaction modules are commonly found in functionally
unrelated proteins, FF domains are primarily present in only three eukaryotic
the splicing factors FBP11 and Prp40,
the transcription factor CA150,
p190 RhoGTPase-related proteins.
FF domains are found singly or in multiple copies but the number of FF domains
in protein sequences ranges, in general, between two and six [1,2,3,4,5,6].
The FF domain is composed of three α-helices arranged in an orthogonal
bundle with a 3(10) helix in the loop between the second and third α
helices (see <PDB:1H40>). The two highly conserved phenylalanine residues are
in the middle of the first and third α helices, and form part of the
hydrophobic core of the protein [3,4,5,6.].
The profile we developed covers the entire FF domain.
June 2013 / First entry.
PROSITE method (with tools and information) covered by this documentation:
Bedford M.T., Leder P.
The FF domain: a novel motif that often accompanies WW domains.
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