title: Regulation of scleraxis function by interaction with the bHLH protein E47.
abstract: Scleraxis is a basic helix-loop-helix (bHLH) protein whose function has been postulated to be preconfigurative of sclerotomal mesenchymal patterning during early embryonic development by regulating expression of differentiation-specific genes, particularly those involved in chondrogenesis. To gain understanding of the molecular action of scleraxis we test the hypothesis that it heterodimerizes with another bHLH protein to activate gene expression. Transient coexpression of scleraxis and E47, a candidate bHLH protein, showed that scleraxis dimerizes with E47 in vivo and that this complex binds to a classic E-box DNA sequence better than either factor alone. Further, when expressed together, scleraxis and E47 synergistically enhanced transcription from a promoter containing multiple E-box binding sites.
authors.affiliation: Department of Orthopaedic Surgery, Thomas Jefferson University, 501 Curtis, 1015 Walnut, Philadelphia, Pennsylvania, 19107, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Carlberg
authors.forename: R S
authors.initials: RS
authors.lastname: Tuan
authors.forename: D J
authors.initials: DJ
authors.lastname: Hall
mesh_terms: D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D002460:Cell Line; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D019281:Dimerization; D018257:Helix-Loop-Helix Motifs; D006801:Humans; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism; D051820:TCF Transcription Factors; D058125:Transcription Factor 7-Like 1 Protein; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology*
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; D051820:TCF Transcription Factors; D058125:Transcription Factor 7-Like 1 Protein; D014157:Transcription Factors; C093504:SCX protein, human; C544912:TCF7L1 protein, human