PDBsum entry 3m5b

Transcription

PDB id: 3m5b

Contents

Protein chains

109 a.a. *

Waters ×154

* Residue conservation analysis

PDB id:

3m5b

Name:

Transcription

Title:

Crystal structure of the btb domain from fazf/zbtb32

Structure:

Zinc finger and btb domain-containing protein 32. Chain: a, b. Fragment: btb domain from fazf/zbtb32. Synonym: fanconi anemia zinc finger protein, testis zinc finger protein, fancc-interacting protein. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: fazf, tzfp, zbtb32. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.00Å R-factor: 0.189 R-free: 0.244

Authors:

P.J.Stogios,N.C.Pomroy,G.G.Prive

Key ref:

P.J.Stogios et al. (2010). Insights into strand exchange in BTB domain dimers from the crystal structures of FAZF and Miz1. J Mol Biol, 400, 983-997. PubMed id: 20493880

Date:

12-Mar-10 Release date: 09-Jun-10

Protein chains

Q9Y2Y4  (ZBT32_HUMAN) -  Zinc finger and BTB domain-containing protein 32 from Homo sapiens

Seq: 487 a.a.

Struc: 109 a.a.

J Mol Biol 400:983-997 (2010)

PubMed id: 20493880

Insights into strand exchange in BTB domain dimers from the crystal structures of FAZF and Miz1.

P.J.Stogios, J.A.Cuesta-Seijo, L.Chen, N.C.Pomroy, G.G.Privé.

ABSTRACT

The BTB domain is a widely distributed protein-protein interaction motif that is often found at the N-terminus of zinc-finger transcription factors. Previous crystal structures of BTB domains have revealed tightly interwound homodimers, with the N-terminus from one chain forming a two stranded antiparallel beta-sheet with a strand from the other chain. We have solved the crystal structures of the BTB domains from FAZF and Miz1 to resolutions of 2.0 A and 2.6 A, respectively. Unlike previous examples of BTB domain structures, the FAZF BTB domain is a non-swapped dimer with each N-terminal beta-strand associated with its own chain. As a result, the dimerization interface in the FAZF BTB domain is about half as large as in the domain-swapped dimers. The Miz1 BTB domain resembles a typical swapped BTB dimer, although it has a shorter N-terminus that is not able to form the interchain sheet. Using cysteine crosslinking, we confirmed that the PLZF BTB dimer is strand-exchanged in solution while the FAZF BTB dimer is not. A phylogenic tree of the BTB fold based on both sequence and structural features shows that the common ancestor of the BTB domain in the BTB-ZF proteins was a domain-swapped dimer. The differences in the N-termini seen in the FAZF and Miz1 BTB domains appear to be more recent developments in the structural evolution of the domain.