Poster abstracts

Poster number 10 submitted by Medha Raina

Association of a multi-synthetase complex with translating ribosomes in the archaeon Thermococcus kodakarensis

Medha Raina (Microbiology, The Ohio State University), Sara Elgamal (Microbiology, The Ohio State University), Thomas J. Santangelo (Microbiology, The Ohio State University), Michael Ibba (Microbiology, The Ohio State University)

Abstract:
In archaea and eukaryotes aminoacyl-tRNA synthetases (aaRSs) associate in multi-synthetase complexes (MSCs), however the role of such MSCs in translation is unknown. MSC function was investigated in vivo in the archaeon Thermococcus kodakarensis, wherein six aaRSs were affinity co-purified together with several other factors involved in protein synthesis, suggesting that MSCs may interact directly with translating ribosomes. In support of this hypothesis, the aminoacyl-tRNA synthetase (aaRS) activities of the MSC were enriched in isolated T. kodakarensis polysome fractions. These data indicate that components of the archaeal protein synthesis machinery associate into macromolecular assemblies in vivo and provide the potential to increase translation efficiency by limiting substrate diffusion away from the ribosome, thus facilitating rapid recycling of tRNAs.

References:
1) Kaminska, M., Havrylenko, S., Decottignies, P., Le Marechal, P., Negrutskii, B. and Mirande, M. (2009). Dynamic organization of aminoacyl-tRNA synthetase complexes in the cytoplasm of human cells. J. Biol. Chem. 284, 13746-13754.

2) Negrutskii BS & Deutscher MP (1991) Channeling of aminoacyl-tRNA for protein synthesis in vivo. Proceedings of the National Academy of Sciences of the United States of America 88(11):4991-4995.

3) Praetorius-Ibba, M., Hausmann, C.D., Paras, M., Rogers, T.E. and Ibba, M. (2007).Functional association between three archaeal aminoacyl-tRNA synthetases. J. Biol.Chem. 282, 3680-3687.

Keywords: Aminoacyl-tRNA synthetase, archaea, translation