title: HCF-1 self-association via an interdigitated Fn3 structure facilitates transcriptional regulatory complex formation.
abstract: Host-cell factor 1 (HCF-1) is an unusual transcriptional regulator that undergoes a process of proteolytic maturation to generate N- (HCF-1(N)) and C- (HCF-1(C)) terminal subunits noncovalently associated via self-association sequence elements. Here, we present the crystal structure of the self-association sequence 1 (SAS1) including the adjacent C-terminal HCF-1 nuclear localization signal (NLS). SAS1 elements from each of the HCF-1(N) and HCF-1(C) subunits form an interdigitated fibronectin type 3 (Fn3) tandem repeat structure. We show that the C-terminal NLS recruited by the interdigitated SAS1 structure is required for effective formation of a transcriptional regulatory complex: the herpes simplex virus VP16-induced complex. Thus, HCF-1(N)-HCF-1(C) association via an integrated Fn3 structure permits an NLS to facilitate formation of a transcriptional regulatory complex.
authors.affiliation: Department of Biological Sciences and Graduate School of Nanoscience and Technology, World Class University, Korea Advanced Institute of Science and Technology, Institute for the BioCentury, KAIST, Daejeon 305-701, Korea.
authors.forename: Jihye
authors.initials: J
authors.lastname: Park
authors.forename: Fabienne
authors.initials: F
authors.lastname: Lammers
authors.forename: Winship
authors.initials: W
authors.lastname: Herr
authors.forename: Ji-Joon
authors.initials: JJ
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D005786:Gene Expression Regulation; D051863:Host Cell Factor C1 / Q000737:chemistry / Q000502:physiology*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals; D020080:Tandem Repeat Sequences; D014158:Transcription, Genetic
chemical_list: C497692:HCFC1 protein, human; D051863:Host Cell Factor C1; D019913:Nuclear Localization Signals