5JMV

Crystal structure of mjKae1-pfuPcc1 complex

Summary for 5JMV

• Entry DOI: 10.2210/pdb5jmv/pdb
• Descriptor: Probable bifunctional tRNA threonylcarbamoyladenosine biosynthesis protein, Uncharacterized protein, ADENOSINE MONOPHOSPHATE, ... (4 entities in total)
• Functional Keywords: trna modification, transferase
• Biological source: Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440); More
• Cellular location: Cytoplasm : Q58530
• Total number of polymer chains: 8
• Total formula weight: 166194.10

Authors

Wan, L.,Sicheri, F. (deposition date: 2016-04-29, release date: 2016-07-06, Last modification date: 2023-09-27)

Primary citation

Wan, L.C.,Pillon, M.C.,Thevakumaran, N.,Sun, Y.,Chakrabartty, A.,Guarne, A.,Kurinov, I.,Durocher, D.,Sicheri, F.
Structural and functional characterization of KEOPS dimerization by Pcc1 and its role in t6A biosynthesis.
Nucleic Acids Res., 44:6971-6980, 2016

PubMed Abstract: KEOPS is an ancient protein complex required for the biosynthesis of N6-threonylcarbamoyladenosine (t(6)A), a universally conserved tRNA modification found on all ANN-codon recognizing tRNAs. KEOPS consist minimally of four essential subunits, namely the proteins Kae1, Bud32, Cgi121 and Pcc1, with yeast possessing the fifth essential subunit Gon7. Bud32, Cgi121, Pcc1 and Gon7 appear to have evolved to regulate the central t(6)A biosynthesis function of Kae1, but their precise function and mechanism of action remains unclear. Pcc1, in particular, binds directly to Kae1 and by virtue of its ability to form dimers in solution and in crystals, Pcc1 was inferred to function as a dimerization module for Kae1 and therefore KEOPS. We now present a 3.4 Å crystal structure of a dimeric Kae1-Pcc1 complex providing direct evidence that Pcc1 can bind and dimerize Kae1. Further biophysical analysis of a complete archaeal KEOPS complex reveals that Pcc1 facilitates KEOPS dimerization in vitro Interestingly, while Pcc1-mediated dimerization of KEOPS is required to support the growth of yeast, it is dispensable for t(6)A biosynthesis by archaeal KEOPS in vitro, raising the question of how precisely Pcc1-mediated dimerization impacts cellular biology.

PubMed: 27302132
DOI: 10.1093/nar/gkw542

Experimental method

X-RAY DIFFRACTION (3.38646964319 Å)