ICC 2021

Eleni Petsalaki

Eleni Petsalaki, Speaker at Oncology Conference
University of Crete, Greece
Title : A novel mechanism that promotes mitotic spindle formation in cancer cells


During cell division, the mitotic spindle consists mainly of microtubules (MTs) and is essential for accurate distribution of the genetic material to the two daughter cells. Errors in spindle formation can lead to incorrect separation of chromosomes that is associated with tumorigenesis or developmental disorders; however, the molecular mechanisms of mitotic spindle assembly are incompletely understood.
In the present study, we show that Chk1, a kinase involved in the cellular response to DNA damage, is essential for optimal density and effective polymerization of spindle MTs in human cells. Chk1 localizes to the centrosomes (the main centers of MT-organization in animal cells) in mitosis by confocal microscopy. Chk1 phosphorylates purified β-tubulin in kinase reactions in vitro at several conserved residues which were identified by mass ,spectrometry. Furthermore, reduced microtubule density in Chk1-deficient cells associates with formation of disorganized spindles. We propose that Chk1 phosphorylates β-tubulin to promote optimal spindle MT polymerization and spindle assembly.
In conclusion, these findings describe a novel mechanism that could protect against tumorigenesis, through regulating mitotic spindle formation.


Dr Eleni Petsalaki is a Post-Doctoral Research Scientist in Dr George Zachos’ lab at the University of Crete, in Greece. She completed her PhD in 2014 in Molecular Biology and Biomedicine at the Department of Biology in Crete. Her main research interest is to understand mechanisms of mitotic cell division in human cells, such as the mitotic spindle and abscission checkpoints. She has published 14 papers in leading scientific journals (13 first name publications) such as the Journal of Cell Biology (5), Nature Communications (1), Journal of Cell Science (2) and others, and her work has received >200 citations.