We use model gene networks in yeast cells to study a) the dynamics of basic transcriptional regulation, b) the molecular base of epigenetic inheritance of transcriptional states, and c) the mechanism(s) underlying age-related changes in cellular function and gene expression.

Current projects include studies on:

a1) Global transcriptional co-activators and co-repressors (SAGA, Tup1/Ssn6) and their functional interactions with components of the basic transcriptional machinery (General transcription factors, Mediator complex).
a2) Chromatin mediated transcriptional regulation; chromatin remodeling activities (Swi/Snf, SWR-C) and histone variants (H2A.Z) disposition.

b1) Molecular mechanism(s) underlying epigenetic transmission of cellular memory; Identification of cytoplasmicaly inherited factors (signal transducers and/or regulators of DNA-binding transcriptional regulators) controlling transcriptional states in progeny cells.
b2) Principles on epigenetic inheritance of telomere silencing, used as a model for testing the concept of "self propagating chromatin structure".

c1) Protein quality control machinery: sHsps, Hsp70, Hsp104 and the mechanism(s) of asymmetric segregation of damaged cellular proteins in aged cells.
c2) Age related decline of protein quality control and the molecular base of reduced ability of senescent cells to cope with external challenges.

Selected Publications

Zacharioudakis I. , Gligoris T., Tzamarias D. (2008) A yeast catabolic enzyme controls transcriptional memory. Current Biol. 17: 2041-6.

Gligoris T, Thireos G, Tzamarias D. (2007) The Tup1 corepressor directs H2A.Z deposition at a specific promoter nucleosome marking the GAL1 gene for rapid activation. Mol Cell Biol. 11: 4198-205.

Topalidou, I., Papamichos-Chronakis, M., Thireos, G., Tzamarias D. (2004) Spt3 and Mot1 cooperate in nucleosome remodeling independently of TBP recruitment. EMBO J. 23: 1943-1948.

Papamichos-Chronakis, M., Gligoris, T., Tzamarias D. (2004) The Snf1 kinase controls glucose repression in yeast by modulating interactions between the Mig1 repressor and the Cyc8-Tup1 co-repressor. EMBO Rep. 5: 368-372.

Papamichos-Chronakis, M., Petrakis, T., Ktistaki, E., Tzamarias D. (2002) Cti6, a PHD domain protein bridges the Cyc8-Tup1 corepressor and the SAGA coactivator to overcome repression at GAL1. Molecular Cell 9: 1297-1305.