title: Eos and pegasus, two members of the Ikaros family of proteins with distinct DNA binding activities.
abstract: Members of the Ikaros family of transcription factors, Ikaros, Aiolos, and Helios, are expressed in lymphocytes and have been implicated in controlling lymphoid development. These proteins contain two characteristic clusters of zinc fingers, an N-terminal domain important for DNA recognition, and a C-terminal domain that mediates homo- and heterotypic associations between family members. The conservation of these domains is such that all three proteins recognize related DNA sequences, and all are capable of dimerizing with other family members. Here we describe two additional Ikaros family proteins, Eos and Pegasus. Eos is most highly related to Helios and shares its DNA binding and protein association properties. Pegasus is related to other Ikaros proteins in its C-terminal dimerization domain but contains a divergent N-terminal zinc finger domain. Pegasus self-associates and binds to other family members but recognizes distinct DNA-binding sites. Eos and Pegasus repress the expression of reporter genes containing their recognition elements. Our results suggest that these proteins may associate with previously described Ikaros family proteins in lymphoid cells and play additional roles in other tissues.
authors.affiliation: Department of Biochemistry, G08, University of Sydney, Sydney, New South Wales 2006, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Perdomo
authors.forename: M
authors.initials: M
authors.lastname: Holmes
authors.forename: B
authors.initials: B
authors.lastname: Chong
authors.forename: M
authors.initials: M
authors.lastname: Crossley
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019281:Dimerization; D006801:Humans; D051740:Ikaros Transcription Factor; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D016335:Zinc Fingers
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C497239:IKZF1 protein, human; C111431:IKZF2 protein, human; C418108:IKZF5 protein, human; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D014157:Transcription Factors; C497238:Zfpn1a1 protein, mouse; C491746:Zfpn1a2 protein, mouse; C118760:Zfpn1a4 protein, mouse; D051740:Ikaros Transcription Factor