2o49: Difference between revisions

Special AT-rich sequence binding protein 1 (SATB1) regulates gene expression essential in immune T-cell maturation and switching of fetal globin species, by binding to matrix attachment regions (MARs) of DNA and inducing a local chromatin remodeling. Previously we have revealed a five-helix structure of the N-terminal CUT domain, which is essentially the folded region in the MAR-binding domain, of human SATB1 by NMR. Here we determined crystal structure of the complex of the CUT domain and a MAR DNA, in which the third helix of the CUT domain deeply enters the major groove of DNA in the B-form. Bases of 5'-CTAATA-3' sequence are contacted by this helix, through direct and water-mediated hydrogen bonds and apolar and van der Waals contacts. Mutations at conserved base-contacting residues, Gln402 and Gly403, reduced the DNA-binding activity, which confirmed the importance of the observed interactions involving these residues. A significant number of equivalent contacts are observed also for typically four-helix POU-specific domains of POU-homologous proteins, indicating that these domains share a common framework of the DNA-binding mode, recognizing partially similar DNA sequences.

Structural basis for recognition of the matrix attachment region of DNA by transcription factor SATB1., Yamasaki K, Akiba T, Yamasaki T, Harata K, Nucleic Acids Res. 2007;35(15):5073-84. Epub 2007 Jul 25. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17652321 17652321]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:14:15 2008''