title: Basic Tilted Helix Bundle - a new protein fold in human FKBP25/FKBP3 and HectD1.
abstract: In this paper, we describe the structure of a N-terminal domain motif in nuclear-localized FKBP251-73, a member of the FKBP family, together with the structure of a sequence-related subdomain of the E3 ubiquitin ligase HectD1 that we show belongs to the same fold. This motif adopts a compact 5-helix bundle which we name the Basic Tilted Helix Bundle (BTHB) domain. A positively charged surface patch, structurally centered around the tilted helix H4, is present in both FKBP25 and HectD1 and is conserved in both proteins, suggesting a conserved functional role. We provide detailed comparative analysis of the structures of the two proteins and their sequence similarities, and analysis of the interaction of the proposed FKBP25 binding protein YY1. We suggest that the basic motif in BTHB is involved in the observed DNA binding of FKBP25, and that the function of this domain can be affected by regulatory YY1 binding and/or interactions with adjacent domains.
authors.affiliation: Department of Physics, Chemistry and Biology, Division of Chemistry, Linköping University, SE-58183 Linköping, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Helander
authors.affiliation: Department of Physics, Chemistry and Biology, Division of Chemistry, Linköping University, SE-58183 Linköping, Sweden.
authors.forename: Meri
authors.initials: M
authors.lastname: Montecchio
authors.affiliation: Northeast Structural Genomics Consortium and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.
authors.forename: Alexander
authors.initials: A
authors.lastname: Lemak
authors.affiliation: Northeast Structural Genomics Consortium and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.
authors.forename: Christophe
authors.initials: C
authors.lastname: Farès
authors.affiliation: Department of Physics, Chemistry and Biology, Division of Chemistry, Linköping University, SE-58183 Linköping, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Almlöf
authors.affiliation: Structural Genomics Consortium, Northeast Structural Genomics Consortium, Ontario, Canada.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Northeast Structural Genomics Consortium and Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada.
authors.forename: Adelinda
authors.initials: A
authors.lastname: Yee
authors.affiliation: Structural Genomics Consortium, Northeast Structural Genomics Consortium, Ontario, Canada.|Cancer Institute and Department of Medical Biophysics, University of Toronto, Ontario, Canada.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Arrowsmith
authors.affiliation: Structural Genomics Consortium, Northeast Structural Genomics Consortium, Ontario, Canada.
authors.forename: Sirano
authors.initials: S
authors.lastname: DhePaganon
authors.affiliation: Department of Physics, Chemistry and Biology, Division of Chemistry, Linköping University, SE-58183 Linköping, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Sunnerhagen
mesh_terms: D000595:Amino Acid Sequence; D006801:Humans; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D022021:Tacrolimus Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry*; D050986:YY1 Transcription Factor / Q000378:metabolism
chemical_list: D022021:Tacrolimus Binding Proteins; D044767:Ubiquitin-Protein Ligases; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; C074856:FKBP3 protein, human; C000588989:HECTD1 protein, human
keywords: FKBP25; FKBP3; HectD1; Immunophillins; NMR structure; Structural genomics; YY1