Athanasios (Sakis) Theologis

Athanasios (Sakis) TheologisDuring his career at the PGEC, Sakis made major discoveries in the molecular mechanisms of hormone action. For example, he cloned the gene for ACC synthase. ACC catalyzes the first step in ethylene biosynthesis, and he used it to regulate ripening in tomato. In his most recent paper, a tour-de-force typical of Sakis' s work, he extensively characterized the ACC synthase family in Arabidopsis. He also showed that the hormone auxin rapidly stimulates transcription of certain genes, setting the stage for the explosion of research on auxin signaling, in his lab and in others. He had the vision, with Ron Davis and Joe Ecker, to organize a multinational group to sequence the genome of Arabidopsis thaliana, and specifically carried out a detailed analysis of Chromosome 1. 

Selected References: 

Sato, T., and Theologis, A. (1989) Cloning the messenger encoding 1-aminocyclopropane-1-carboxylate synthase, the key enzyme for ethylene biosynthesis in plants. Proc. Natl. Acad. Sci. USA 86: 6621Ð6625.

Oeller, P.W., Lu, M.W., Taylor, L.P., Pike, D.A. and Theologis, A. (1991) Reversible inhibition of tomato fruit senescence by antisense RNA. Science 254:437-439.

Abel, S., Nguyen, M.D., and Theologis, A. (1995) The PS-IAA4/5-like family of early aixin-inducible mRNAs in Arabidopsis thaliana. J. Mol. Biol. 251: 533-549.

Arabidopsis Genome Initiative. (2000) Analysis of the genome sequence of the flowering plant Arabidopsis thaliana. Nature, 408:796-815.

Theologis, A., Ecker, J. R., Palm, C. J. et al. (2000) Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana. Nature, 408:816-820.

Okushima, Y., Overvoorde, P. J., Arima, K., Alonso, J. M., Chan, A., Chang, C., Ecker, J. R., Hughes, B., Lui, A., Nguyen, D., Onodera, C., Quach, H., Smith, A., Yu, G., and Theologis A. (2005) Functional Genomic Analysis of the AUXIN RESPONSE FACTOR (ARF) Gene Family Members in Arabidopsis thaliana: Unique and Overlapping Functions of ARF7 and ARF19. Plant Cell 17: 444-463.

Tsuchisaka, A. Yu, G., Jin, H., Alonso, J.M., Ecker, J.R., Zhang, X., Gao, S. and Theologis, A. (2009) A Combinatorial Interplay Among the 1-Aminocyclopropane-1-Carboxylate Isoforms Regulates Ethylene Biosynthesis in Arabidopsis thaliana. Genetics 183: 979 - 1003.