3NFQ

Crystal structure of the conserved central domain of yeast Spn1/Iws1

Summary for 3NFQ

• Entry DOI: 10.2210/pdb3nfq/pdb
• Descriptor: Transcription factor IWS1 (2 entities in total)
• Functional Keywords: spn1, transcription, rna polymerase ii
• Biological source: Saccharomyces cerevisiae (yeast)
• Cellular location: Nucleus: Q06505
• Total number of polymer chains: 2
• Total formula weight: 39368.54

Authors

Stargell, L.A.,Luger, K. (deposition date: 2010-06-10, release date: 2010-10-13, Last modification date: 2024-10-30)

Primary citation

Pujari, V.,Radebaugh, C.A.,Chodaparambil, J.V.,Muthurajan, U.M.,Almeida, A.R.,Fischbeck, J.A.,Luger, K.,Stargell, L.A.
The Transcription Factor Spn1 Regulates Gene Expression via a Highly Conserved Novel Structural Motif.
J.Mol.Biol., 404:1-15, 2010

PubMed Abstract: Spn1/Iws1 plays essential roles in the regulation of gene expression by RNA polymerase II (RNAPII), and it is highly conserved in organisms ranging from yeast to humans. Spn1 physically and/or genetically interacts with RNAPII, TBP (TATA-binding protein), TFIIS (transcription factor IIS), and a number of chromatin remodeling factors (Swi/Snf and Spt6). The central domain of Spn1 (residues 141-305 out of 410) is necessary and sufficient for performing the essential functions of SPN1 in yeast cells. Here, we report the high-resolution (1.85 Å) crystal structure of the conserved central domain of Saccharomyces cerevisiae Spn1. The central domain is composed of eight α-helices in a right-handed superhelical arrangement and exhibits structural similarity to domain I of TFIIS. A unique structural feature of Spn1 is a highly conserved loop, which defines one side of a pronounced cavity. The loop and the other residues forming the cavity are highly conserved at the amino acid level among all Spn1 family members, suggesting that this is a signature motif for Spn1 orthologs. The locations and the molecular characterization of temperature-sensitive mutations in Spn1 indicate that the cavity is a key attribute of Spn1 that is critical for its regulatory functions during RNAPII-mediated transcriptional activity.

PubMed: 20875428
DOI: 10.1016/j.jmb.2010.09.040

Experimental method

X-RAY DIFFRACTION (1.85 Å)