Related Experiment Video
Updated: Jun 21, 2025

Live Cell Imaging to Assess the Dynamics of Metaphase Timing and Cell Fate Following Mitotic Spindle Perturbations
Published on: September 20, 2019
Kinase activity of histone chaperone APLF maintains steady state of centrosomes in mouse embryonic stem cells
Sruthy Manuraj Rajam1, Pallavi Chinnu Varghese2, Mayur Balkrishna Shirude1
1Rajiv Gandhi Centre for Biotechnology (RGCB), Regenerative Biology Program, Thycaud PO, Poojappura, Thiruvananthapuram, Kerala 695014, India; Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India.
Abstract:
Our recent studies revealed the role of mouse Aprataxin PNK-like Factor (APLF) in development. Nevertheless, the comprehensive characterization of mouse APLF remains entirely unexplored. Based on domain deletion studies, here we report that mouse APLF's Acidic Domain and Fork Head Associated (FHA) domain can chaperone histones and repair DNA like the respective human orthologs. Immunofluorescence studies in mouse embryonic stem cells showed APLF co-localized with γ-tubulin within and around the centrosomes and govern the number and integrity of centrosomes via PLK4 phosphorylation. Enzymatic analysis established mouse APLF as a kinase. Docking studies identified three putative ATP binding sites within the FHA domain. Site-directed mutagenesis showed that R37 residue within the FHA domain is indispensable for the kinase activity of APLF thereby regulating the centrosome number. These findings might assist us comprehend APLF in different pathological and developmental conditions and reveal non-canonical kinase activity of proteins harbouring FHA domains that might impact multiple cellular processes.
Related Concept Videos
Histone Variants at the Centromere
Separation of Sister Chromatids
At the onset of anaphase, separase, a proteolytic enzyme, is...
Anaphase Promoting Complex
The Spindle Assembly Checkpoint
Many proteins function together to control the spindle assembly checkpoint. Mutations affecting these proteins may allow cells to proceed into anaphase prematurely, resulting in the...
Maintenance of the ES Cell State
Disassembly of Intermediate Filaments
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...

