Luminal acetylation of microtubules is not essential for Plasmodium berghei and Toxoplasma gondii survival
Authors:Thrishla Kumar1,a, Katharina Röver2,a, Johannes F. Stortz3,a, Annika M. Binder2,a, Benjamin Spreng2, Madlen Konert2, Markus Meissner1, Friedrich Frischknecht2,4 and Elena Jimenez-Ruiz1,*
doi: 10.15698/mic2025.12.863
Volume 12, pp. 299 to 313, published 17/12/2025.
1 Experimental Parasitology, Veterinary Medicine Faculty, Ludwig-Maximilians-Universität Munich, Germany. 2 Parasitology, Center for Infectious Diseases, Medical Faculty, Heidelberg University, Im Neuenheimer Feld 344, 69120 Heidelberg, Germany. 3 Centre for Parasitology, University of Glasgow, United Kingdom. 4 German Center for Infectious Diseases, partner site Heidelberg.
a Equal contribution.
Keywords:
microtubule acetylation, K40 acetylation, tubulin modifications, apicomplexan parasites, parasite cytoskeleton
Corresponding Author(s):
Conflict of interest statement:
The authors declare no conflict of interest.
Please cite this article as:
Thrishla Kumar, Katharina Röver, Johannes F. Stortz, Annika M. Binder, Benjamin Spreng, Madlen Konert, Markus Meissner, Friedrich Frischknecht, Elena Jimenez-Ruiz (2025). Luminal acetylation of microtubules is not essential for Plasmodium berghei and Toxoplasma gondii survival. Microbial Cell 12: 299–313. doi: 10.15698/mic2025.12.863
© 2025 Kumar et al. This is an open-access article released under the terms of the Creative Commons Attribution (CC BY) license, which allows the unrestricted use, distribution, and reproduction in any medium, provided the original author and source are acknowledged.
Abstract:
Post-translational modifications of microtubules regulate their stability and dynamics. Acetylation of α tubulin at lysine 40 (K40) by α-acetyltransferase (TAT) occurs on the luminal side of microtubules, stabilizes their structure, and plays essential roles in various cellular processes across eukaryotes. Apicomplexan parasites include the malaria-causing Plasmodium species and Toxoplasma gondii, both of which possess unusually stable subpellicular microtubules, a set of cytoskeletal filaments underlying the parasite’s inner membrane complex. Interestingly, while Toxoplasma gondii and human-infecting Plasmodium species retain both K40 and αTAT, rodent-infecting Plasmodium species have lost αTAT, and K40 has been replaced by glutamine (Q40), a residue that can mimic acetylated lysine. Here, we investigate the role of microtubule acetylation in apicomplexan parasites by generating and characterizing genetic mutants in Plasmodium berghei and Toxoplasma gondii. In Plasmodium
berghei, introduction of a Q40K mutation in α1 tubulin did not affect parasite development or infectivity, suggesting that the absence of K40 acetylation is not detrimental. In Toxoplasma gondii, we confirmed that αTAT is responsible for microtubule acetylation but, contrary to previous reports, its deletion had no impact on parasite growth in vitro. Together, these results indicate that luminal K40 acetylation is not essential for microtubule function in either species, pointing to functional redundancy and highlighting the plasticity of cytoskeletal regulation in apicomplexan parasites.