PDBsum entry 4xah

Protein binding

PDB id: 4xah

Contents

Protein chains

177 a.a.

Waters ×383

PDB id:

4xah

Name:

Protein binding

Title:

X-ray crystal structure of s. Cerevisiae cgi121

Structure:

Ekc/keops complex subunit cgi121. Chain: a, b. Synonym: cgi-121 homolog. Engineered: yes

Source:

Saccharomyces cerevisiae (strain atcc 204508 / s288c). Baker's yeast. Organism_taxid: 559292. Gene: cgi121, yml036w. Expressed in: escherichia coli 'bl21-gold(de3)plyss ag'. Expression_system_taxid: 866768

Resolution:

2.50Å R-factor: 0.188 R-free: 0.237

Authors:

W.Zhang,M.Graille,B.Collinet,H.Van Tilbeurgh

Key ref:

W.Zhang et al. (2015). Crystal structures of the Gon7/Pcc1 and Bud32/Cgi121 complexes provide a model for the complete yeast KEOPS complex. Nucleic Acids Res, 43, 3358-3372. PubMed id: 25735745 DOI: 10.1093/nar/gkv155

Date:

14-Dec-14 Release date: 18-Mar-15

Protein chains

Q03705  (CG121_YEAST) -  EKC/KEOPS complex subunit CGI121 from Saccharomyces cerevisiae (strain ATCC 204508 / S288c)

Seq: 181 a.a.

Struc: 177 a.a.*

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

DOI no: 10.1093/nar/gkv155

Nucleic Acids Res 43:3358-3372 (2015)

PubMed id: 25735745

Crystal structures of the Gon7/Pcc1 and Bud32/Cgi121 complexes provide a model for the complete yeast KEOPS complex.

W.Zhang, B.Collinet, M.Graille, M.C.Daugeron, N.Lazar, D.Libri, D.Durand, H.van Tilbeurgh.

ABSTRACT

The yeast KEOPS protein complex comprising Kae1, Bud32, Cgi121, Pcc1 and Gon7 is responsible for the essential tRNA threonylcarbamoyladenosine (t(6)A) modification. Deletion of genes coding for the KEOPS subunits also affects telomere elongation and transcriptional regulation. In the present work, the crystal structure of Bud32/Cgi121 in complex with ADP revealed that ADP is bound in the catalytic site of Bud32 in a canonical manner characteristic of Protein Kinase A (PKA) family proteins. We found that Gon7 forms a stable heterodimer with Pcc1 and report the crystal structure of the Pcc1-Gon7 heterodimer. Gon7 interacts with the same Pcc1 region engaged in the archaeal Pcc1 homodimer. We further show that yeast KEOPS, unlike its archaeal counterpart, exists as a heteropentamer in which Gon7, Pcc1, Kae1, Bud32 and Cgi121 also adopt a linear arrangement. We constructed a model of yeast KEOPS that provides structural insight into the role of Gon7. The model also revealed the presence of a highly positively charged crater surrounding the entrance of Kae1 that likely binds tRNA.