PLK4 trans-Autoactivation Controls Centriole Biogenesis in Space

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Centrioles are vital for cilia and centrosome formation.
• The spatial regulation of centriole biogenesis has been a long-standing question in cell biology.

Purpose of the Study:

• To investigate the mechanism controlling the spatial localization of centriole biogenesis.
• To elucidate the role of Polo-like kinase 4 (PLK4) in this process.

Main Methods:

• Investigated the trans-autoactivation of PLK4.
• Studied the recruitment and local accumulation of PLK4 by existing centrioles.
• Examined the effect of concentrating PLK4 in peroxisomes.
• Analyzed the impact of varying PLK4 overexpression levels on centriole biogenesis.

Main Results:

• Centrioles promote PLK4 activation through recruitment and local accumulation.
• Reduced PLK4 activity upon centriole removal can be rescued by targeting PLK4 to peroxisomes.
• Mild PLK4 overexpression leads to amplification at existing centrioles.
• High PLK4 levels induce both existing and de novo centriole formation.

Conclusions:

• Centrioles spatially regulate their own biogenesis by promoting local PLK4 activation.
• This mechanism favors the formation of new centrioles adjacent to existing ones.
• Similar spatial control mechanisms likely apply to other centriole components.