The organization of the archaeal cell

Introduction

Archaea are microbes that form one of the three domains of life. While sharing similarities with both Bacteria and Eukarya, archaea possess unique features such as atypical lipid membranes, the archaellum motility apparatus, and exclusive metabolic pathways like methanogenesis.

Recent Advances in Archaeal Research

Studies over the last decade have substantially expanded the archaeal tree of life, revealing the tremendous diversity, widespread distribution, and vital ecological roles mediated by these organisms, as well as their crucial evolutionary placement as close relatives of eukaryotes. Despite these major advances regarding archaeal diversity, ecology, and evolution, our knowledge of archaeal cell biology remains limited, particularly due to the scarcity of model systems and suitable genetic and imaging tools.

Project Overview: ARCHCELLORG

In ARCHCELLORG, we propose to explore recent methodological advances, including the ability to perform live cell imaging on the model archaeon Haloferax volcanii, combined with genetics, physiology, biochemistry, and structural approaches, to unravel the mechanisms governing three fundamental aspects of archaeal cellular organization:

1. Cell division
2. Polarity
3. Shape regulation

Aim 1: Cell Division

In Aim 1, we will elucidate the molecular composition of the archaeal division machinery and the mechanisms involved in its organization and placement at the division plane.

Aim 2: Cell Polarity

In Aim 2, we will identify the main regulators of cell polarity and characterize their modes of action.

Aim 3: Shape Regulation

In Aim 3, we will investigate regulators of shape transition and define the mechanisms by which they coordinate shape changes and motility.

Conclusion

Elucidating these processes will not only contribute to furthering our understanding of archaeal cell organization but will likely also provide valuable insights into the evolution of cellular life on Earth, including the processes that led to the emergence of eukaryotes.