PDBsum entry 3oux

Protein binding

PDB id: 3oux

Contents

Protein chains

503 a.a. *

47 a.a. *

Waters ×97

* Residue conservation analysis

PDB id:

3oux

Name:

Protein binding

Title:

Structure of beta-catenin with phosphorylated lef-1

Structure:

Catenin beta-1. Chain: a. Synonym: beta-catenin. Engineered: yes. Lymphoid enhancer-binding factor 1. Chain: b. Synonym: lef-1. Engineered: yes

Source:

Mus musculus. Mouse. Organism_taxid: 10090. Gene: ctnnb1, catnb. Expressed in: escherichia coli. Expression_system_taxid: 562. Gene: lef1, lef-1.

Resolution:

2.40Å R-factor: 0.199 R-free: 0.264

Authors:

W.I.Weis,J.Sun

Key ref:

J.Sun and W.I.Weis (2011). Biochemical and structural characterization of β-catenin interactions with nonphosphorylated and CK2-phosphorylated Lef-1. J Mol Biol, 405, 519-530. PubMed id: 21075118

Date:

15-Sep-10 Release date: 24-Nov-10

Protein chain

Q02248  (CTNB1_MOUSE) -  Catenin beta-1 from Mus musculus

Seq: 781 a.a.

Struc: 503 a.a.

Protein chain

P27782  (LEF1_MOUSE) -  Lymphoid enhancer-binding factor 1 from Mus musculus

Seq: 397 a.a.

Struc: 47 a.a.

J Mol Biol 405:519-530 (2011)

PubMed id: 21075118

Biochemical and structural characterization of β-catenin interactions with nonphosphorylated and CK2-phosphorylated Lef-1.

J.Sun, W.I.Weis.

ABSTRACT

In the Wnt/β-catenin signaling pathway, β-catenin activates target genes through its interactions with the T-cell factor/lymphoid enhancer-binding factor (TCF/Lef) family of transcription factors. The crystal structures of complexes between the β-catenin armadillo domain and the Lef-1 N-terminal domain show that the overall conformation and many of the interactions are similar to other published structures of TCFs bound to β-catenin. However, a second salt bridge in other TCF-β-catenin structures is absent in the structure of β-catenin-Lef-1 complex, indicating that this feature is not obligatory for β-catenin binding. Casein kinase II (CK2) has been shown to act as a positive regulator of Wnt signaling, and Lef-1 is a substrate of CK2. In vitro phosphorylation of purified Lef-1 was used to examine the effect of CK2 on the interaction of Lef-1 with β-catenin. Mass spectrometry data show that CK2 phosphorylation of Lef-1 N-terminal domain results in a single phosphorylation site at Ser40. Isothermal titration calorimetry revealed that β-catenin binds to nonphosphorylated or CK2-phosphorylated Lef-1 with the same affinity, which is consistent with the absence of phospho-Ser40 interactions in the crystal structure of phosphorylated Lef-1 N-terminal domain bound to β-catenin. These data indicate that the effect of CK2 on the Wnt/β-catenin pathway does not appear to be at the level of the Lef-1-β-catenin interaction.