Novel zinc finger motif in the basal transcriptional machinery : three-dimensional NMR studies of the nucleic acid binding domain of transcriptional elongation factor TFIIS

• Main Authors: Gozani, Shai N., Weiss, Michael A., Qian, Xiuqi, Yoon, Ho Sup, Jeon, Choon Ju, Agarwal, Kan
• Other Authors: School of Biological Sciences
• Format: Article
• Language: English
• Published: 2012
• Subjects: DRNTU::Science::Biological sciences::Biochemistry
• Online Access: https://hdl.handle.net/10356/94285; http://hdl.handle.net/10220/7481
• Institution: Nanyang Technological University

Transcriptional elongation provides a key control point in the regulation of eukaryotic gene expression. Here we describe homonuclear and lSN-heteronuclear 3D NMR studies of the nucleic acid binding domain of human transcriptional elongation factor TFIIS. This domain contains a Cys4 ZnZ+- binding site with no homology to previously characterized Cys4, Cysa, or Cysz-His2 Zn fingers. Complete lH and I5N NMR resonance assignment of a 50-residue TFIIS peptideZnz+ complex is obtained. Its solution structure, as determined by distance geometry/simulated annealing (DG/SA) calculations, exhibits a novel three-stranded antiparallel p-sheet (designated the Zn ribbon). Analogous sequence motifs occur in a wide class of proteins involved in RNA or DNA transactions, including human basal transcriptional initiation factor TFIIE. A three-dimensional model of the TFIIE Cys4 domain is obtained by DG-based homology modeling. The role of the TFIIS Zn ribbon in the control of eukaryotic transcriptional elongation is discussed.