PDBsum entry 3esl

Cell cycle

PDB id: 3esl

Contents

Protein chains

195 a.a. *

Ligands

NHE ×2

Waters ×237

* Residue conservation analysis

PDB id:

3esl

Name:

Cell cycle

Title:

Crystal structure of the conserved n-terminal domain of the mitotic checkpoint component bub1

Structure:

Checkpoint serine/threonine-protein kinase bub1. Chain: a, b. Fragment: conserved n-terminal domain (residues 29-230). Engineered: yes

Source:

Saccharomyces cerevisiae. Brewer's yeast,lager beer yeast,yeast. Organism_taxid: 4932. Strain: yjm789. Gene: bub1, g7542, ygr188c. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.74Å R-factor: 0.190 R-free: 0.216

Authors:

V.M.Bolanos-Garcia,D.Y.Chirgadze,T.L.Blundell

Key ref:

V.M.Bolanos-Garcia et al. (2009). The Crystal Structure of the N-Terminal Region of BUB1 Provides Insight into the Mechanism of BUB1 Recruitment to Kinetochores. Structure, 17, 105-116. PubMed id: 19141287 DOI: 10.1016/j.str.2008.10.015

Date:

06-Oct-08 Release date: 17-Feb-09

Protein chains

A6ZUJ9  (A6ZUJ9_YEAS7) -  Budding uninhibited by benzimidazole-related protein from Saccharomyces cerevisiae (strain YJM789)

Seq: 1021 a.a.

Struc: 195 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1016/j.str.2008.10.015

Structure 17:105-116 (2009)

PubMed id: 19141287

The Crystal Structure of the N-Terminal Region of BUB1 Provides Insight into the Mechanism of BUB1 Recruitment to Kinetochores.

V.M.Bolanos-Garcia, T.Kiyomitsu, S.D'Arcy, D.Y.Chirgadze, J.G.Grossmann, D.Matak-Vinkovic, A.R.Venkitaraman, M.Yanagida, C.V.Robinson, T.L.Blundell.

ABSTRACT

The interaction of the central mitotic checkpoint component BUB1 with the mitotic kinetochore protein Blinkin is required for the kinetochore localization and function of BUB1 in the mitotic spindle assembly checkpoint, the regulatory mechanism of the cell cycle that ensures the even distribution of chromosomes during the transition from metaphase to anaphase. Here, we report the 1.74 A resolution crystal structure of the N-terminal region of BUB1. The structure is organized as a tandem arrangement of three divergent units of the tetratricopeptide motif. Functional assays in vivo of native and site-specific mutants identify the residues of human BUB1 important for the interaction with Blinkin and define one region of potential therapeutic interest. The structure provides insight into the molecular basis of Blinkin-specific recognition by BUB1 and, on a broader perspective, of the mechanism that mediates kinetochore localization of BUB1 in checkpoint-activated cells.

Selected figure(s)

Figure 3.
Figure 3. Overall Structure of the N-Terminal Domain of BUB1
(A) The two molecules observed in the crystal asymmetric unit associate to form a dimer with noncrystallographic two-fold symmetry.
(B) The structure viewed 90° rotated along the minor axis.
(C) Electron density for α helices H5, H6, H7, and H9 and the connecting loop (after density modification) contoured at 1.4 σ. The final, refined model is shown using a ball-and-stick representation. The α helices, loops, and side chains are clearly visible in the initial map. Water molecules are shown as red spheres.
(D) Ribbon diagram showing that this domain consists of ten α helices with a core arrangement of a triple repeat of the TPR motif (TPR1 orange; TPR2 magenta; TPR3 cyan).
(E,F) Superposition of the three TPRs of Sc-BUB1[(29-230)]. Each molecule representation was generated with Pymol (DeLano, 2002).

Figure 5.
Figure 5. Analysis of the Hs-BUB1-Blinkin Interaction
(A) Yeast two-hybrid analysis of diverse Hs-BUB1 mutants. The effect of the mutant P23G could not be established as it showed self-activation.
(B) Projection of residues important for binding Blinkin onto the protein surface (salmon color). Residues whose mutation did not compromise the binding with Blinkin are shown in blue.
(C) Mapping of Hs-BUB1 mutations associated with cancer. Residues absent in the deletion mutant Δ76–141 are shown in green and residues E36D, A130S, and H151D in brown.

The above figures are reprinted from an Open Access publication published by Cell Press: Structure (2009, 17, 105-116) copyright 2009.

Figures were selected by the author.