Faustova, Ilona, juhendajaÖrd, Mihkel, juhendajaStrelchenko, Stepan2023-06-192023-06-192023https://hdl.handle.net/10062/90741Cyclin dependent kinases (CDKs) regulate the cell cycle by phosphorylating downstream proteins in an ordered manner. In yeast S. cerevisiae, Cdk1 regulates the cell cycle progression from G1 to M phase. Cdk1 phosphorylation can have various effects on the proteins, for example, they can be activated or targeted for degradation. The latter was used in this work to design a regulatory network for controlled protein expression that could be used in cell factories. For this, Far1-based diphosphodegron tags that are degraded in response to phosphorylation by Cdk1, were used to differentially regulate the levels of the transcriptional repressor TetR. Furthermore, as cell factories require dynamic control of protein levels over the cultivation process, the effect of cell culture density on cell cycle and the degron tags was studied. The work shows that Far1-based degron tags can be used as modular tags to regulate exogenous proteins by switching them on or off in an OD-dependent manner using the endogenous Cdk1 machinery. Finally, it was shown that more complex patterns of regulation can be achieved by inducing expression of cyclins at high OD.engembargoedAccessAttribution-NonCommercial-NoDerivatives 4.0 Internationalcell cyclephosphorylationsynthetic biologyprotein degradationThesis