Identification and characterization of structural and regulatory cell-shape determinants in Haloferax volcanii

Schiller, H.; Kouassi, J.; Hong, Y.; Rados, T.; Kwak, J.; DiLucido, A.; Safer, D.; Marchfelder, A.; Pfeiffer, F.; Bisson-Filho, A.; Schulze, S.; Pohlschroder, M.

doi:10.1101/2023.03.05.531186

bioRxiv · 10.1101/2023.03.05.531186

Identification and characterization of structural and regulatory cell-shape determinants in Haloferax volcanii

Schiller, H.·Kouassi, J.·Hong, Y.·Rados, T.·Kwak, J.·DiLucido, A.·Safer, D.·Marchfelder, A.·Pfeiffer, F.·Bisson-Filho, A.·Schulze, S.·Pohlschroder, M.

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Abstract

Archaea play indispensable roles in global biogeochemical cycles, yet many critical cellular processes, including cell-shape determination, are poorly understood. Haloferax volcanii, a model haloarchaeon, forms rods and disks, depending on growth conditions. Here, we used a combination of iterative proteomics, genetics, and live-cell imaging to identify distinct mutants that only form rods or disks. We compared the proteomes of the mutants with wild-type cells across growth phases, thereby distinguishing between protein abundance changes specific to cell shape and those related to growth phases. The corresponding results indicated a diverse set of proteins, including transporters, transducers, signaling components, and transcriptional regulators, as important for cell-shape determination. We also identified structural proteins, including a previously unknown cytoskeletal element, the Hfx. volcanii actin homolog volactin, which plays a role in disk-shape morphogenesis. In summary, we gleaned important insights into archaeal cell-shape determination, with possible implications for understanding the evolution of cell morphology regulation across domains.

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Schiller, H., Kouassi, J., Hong, Y., Rados, T., Kwak, J., DiLucido, A., Safer, D., Marchfelder, A., Pfeiffer, F., Bisson-Filho, A., Schulze, S., Pohlschroder, M.. 2023-03-05. Identification and characterization of structural and regulatory cell-shape determinants in Haloferax volcanii. https://doi.org/10.1101/2023.03.05.531186

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