PDBsum entry 1sp2

Zinc finger

PDB id: 1sp2

Contents

Protein chain

31 a.a. *

Metals

_ZN

* Residue conservation analysis

PDB id:

1sp2

Name:

Zinc finger

Title:

Nmr structure of a zinc finger domain from transcription factor sp1f2, minimized average structure

Structure:

Sp1f2. Chain: a. Fragment: zinc finger DNA binding domain. Synonym: transcription factor sp1. Engineered: yes. Other_details: does not bind DNA specifically as a single zinc finger

Source:

Synthetic: yes. Homo sapiens. Human. Organism_taxid: 9606

NMR struc:

1 models

Authors:

V.A.Narayan,R.W.Kriwacki,J.P.Caradonna

Key ref:

V.A.Narayan et al. (1997). Structures of zinc finger domains from transcription factor Sp1. Insights into sequence-specific protein-DNA recognition. J Biol Chem, 272, 7801-7809. PubMed id: 9065444 DOI: 10.1074/jbc.272.12.7801

Date:

21-Nov-96 Release date: 21-Apr-97

Protein chain

P08047  (SP1_HUMAN) -  Transcription factor Sp1 from Homo sapiens

Seq: 785 a.a.

Struc: 31 a.a.

DOI no: 10.1074/jbc.272.12.7801

J Biol Chem 272:7801-7809 (1997)

PubMed id: 9065444

Structures of zinc finger domains from transcription factor Sp1. Insights into sequence-specific protein-DNA recognition.

V.A.Narayan, R.W.Kriwacki, J.P.Caradonna.

ABSTRACT

The carboxyl terminus of transcription factor Sp1 contains three contiguous Cys2-His2 zinc finger domains with the consensus sequence Cys-X2-4-Cys-X12-His-X3-His. We have used standard homonuclear two-dimensional NMR techniques to solve the solution structures of synthetic peptides corresponding to the last two zinc finger domains (Sp1f2 and Sp1f3, respectively) of Sp1. Our studies indicate a classical Cys2-His2 type fold for both the domains differing from each other primarily in the conformation of Cys-X2-Cys (beta-type I turn) and Cys-X4-Cys (beta-type II turn) elements. There are, however, no significant differences in the metal binding properties between the Cys-X4-Cys (Sp1f2) and Cys-X2-Cys (Sp1f3) subclasses of zinc fingers. The free solution structures of Sp1f2 and Sp1f3 are very similar to those of the analogous fingers of Zif268 bound to DNA. There is NMR spectral evidence suggesting that the Arg-Asp buttressing interaction observed in the Zif-268.DNA complex is also preserved in unbound Sp1f2 and Sp1f3. Modeling Sp1-DNA complex by overlaying the Sp1f2 and Sp1f3 structures on Zif268 fingers 1 and 2, respectively, predicts the role of key amino acid residues, the interference/protection data, and supports the model of Sp1-DNA interaction proposed earlier.

Selected figure(s)

Figure 8.
Fig. 8. Summary of proposed DNA contacts between Sp1f2 and Sp1f3 with their respective 3-base pair subsites. The proposed amino acid-DNA base contacts are shown by a solid line. The other probable^ amino acid-DNA base interactions within the framework are indicated^ by dotted lines. Note the antiparallel orientation of peptide^ and DNA and absence of any direct contacts with the other C-rich strand of DNA duplex (not shown).

Figure 9.
Fig. 9. A, stereo presentation of the superposition of Sp1f2·avg·min (see "Experimental Procedures") and Zif268 finger 1. Residues 3-27 (excluding the loop between the two Cys residues) of Sp1f2·min·avg (dark) were superimposed on the corresponding residues of Zif268^ finger 1 (light). B, stereo presentation of the superposition of Sp1f3·avg·min (see "Experimental Procedures") and Zif268 finger 2. Residues 3-25 (excluding Pro9) of Sp1f3·min·avg (dark) were superimposed on the corresponding residues of Zif268 finger 2 (light).

The above figures are reprinted by permission from the ASBMB: J Biol Chem (1997, 272, 7801-7809) copyright 1997.

Figures were selected by an automated process.