The aim of this project is to unravel the actors and also mechanisms behind the regulation of the cell cycle in the hyperthermophilic crenarchaeon Sulfolobus acidocaldarius. S. acidocaldarius is a model organism for hyperthermophilic archaea and the cell cycle of this organism has been well studied. Despite that, little is known about the regulatory mechanism and the proteins involved as well as signaling pathways.
From previous studies we know that the replication, transcription and translation machineries in Sulfolobus are similar or homologous to the eukaryotic counterparts. The transcription in Sulfolobus is performed by an RNA polymerase homologous to the eukaryotic RNA polymerase II but with bacterial-like transcription factors. However, proteins homologous to the eukaryotic cyclin dependent kinases are absent in archaea as well as bacterial cell cycle regulators.
Sulfolobus acidocaldarius is the only crenarchaeon that can be synchronized and is therefore suitable for cell cycle studies. In addition, there is now a large set of genetical tools available for this organism which make it possible to create knock-outs, mutations, overexpression etc.
To identify pathways for potential regulatory proteins and also the regulatory mechanisms we aim to use next generation sequencing such as RNA-sequencing, ChIP-sequencing, MS and SMRT-sequencing. The RNA-sequencing will be used for whole transcriptome mapping of knock-outs or mutants to elucidate the effect of a certain regulator or the effect of different growth conditions on the gene expression. The ChIP-sequencing will be used to map the regulon of a particular transcription factor. The SMRT-sequencing and MS will be used to investigate the DNA-methylation and protein phosphorylation and their potential impact on cell cycle regulation in Sulfolobus acidocaldarius.
The findings from this project will shed light on cell cycle and transcription regulatory mechanisms in Sulfolobus acidocaldarius and increase the understanding of the cell biology of the archaeal domain of life. Furthermore, given the similarities between Sulfolobus and the eukaryotes this study may also help to understand the basic mechanism of regulation in eukaryotes as well as evolution and the origin of the eykaryotic cell.