Centriole? Huh?

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129

This is very interesting too:

PLK4 trans-Autoactivation Controls Centriole Biogenesis in Space

DOI: 10.1016/j.devcel.2015.09.020

Centrioles are essential for cilia and centrosome assembly. In centriole-containing cells, centrioles always form juxtaposed to pre-existing ones, motivating a century-old debate on centriole biogenesis control.
trans-autoactivation of Polo-like kinase 4 (PLK4), the trigger of centriole biogenesis, is a critical event in the spatial control of that process.
centrioles promote PLK4 activation through its recruitment and local accumulation.
centrioles promote their assembly locally and disfavor de novo synthesis. Similar mechanisms enforcing the local concentration and/or activity of other centriole components are likely to contribute to the spatial control of centriole biogenesis under physiological conditions.
Why centrioles normally form close to existing centrioles is an intriguing question that has fueled debates about the origin of centrioles as self-replicating entities.
In the future, it will be critical to study the regulation of the “activating” and degron-phosphorylation events in PLK4 and how they generate a lag time during which PLK4 can be active to phosphorylate its substrates in the right place and at the right time. In addition, it will be important to understand when and how during the cell cycle PLK4 reaches its critical concentration threshold to trigger centriole assembly.

This one seems very interesting too, though I don’t quite get it yet.

Acto-myosin force organization modulates centriole separation and PLK4 recruitment to ensure centriole fidelity
Elisa Vitiello, Philippe Moreau, Vanessa Nunes, Amel Mettouchi, Helder Maiato, Jorge G. Ferreira, Irène Wang & Martial Balland
Nature Communications volume 10, Article number: 52 (2019)

centriole duplication needs to be tightly regulated.
The mechanism driving centriole separation is poorly understood and little is known on how this is linked to centriole duplication.
actin-generated forces regulate centriole separation.
precise acto-myosin force arrangements control direction, distance and time of centriole separation.
acto-myosin forces might act in fundamental mechanisms of aneuploidy prevention.
Here we propose a “centriole force sensing” mechanism where acto-myosin forces modulate centriole separation and centrosomal recruitment of PLK4, to ultimately limit centriole duplication at only once per cell cycle.
this mechanism acts as a way for the cell to prevent aberrant duplication and limit possible aneuploidy onset.
130

I see your point.
Can you post a reference to a recent research paper on this topic to illustrate the difference ?
Thanks.

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131

You just did! Don’t you see the relative modesty of the last two real papers you quoted from?

2 Likes
132

Wow! Cool! I didn’t notice it. Thanks for calling my attention at that. Maybe I should add this new skill in my CV. :slight_smile:

modesty? Are the other referenced papers relatively arrogant?

real papers? Are the other papers unreal?

this is a fast-track learning course :slight_smile:

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Centrosome Remodelling in Evolution
Daisuke Ito and MĂłnica Bettencourt-Dias
Cells 2018 7(7), 71; doi:10.3390/cells7070071

The centrosome is the major microtubule organizing centre (MTOC) in animal cells. The canonical centrosome is composed of two **centrioles** surrounded by a pericentriolar matrix (PCM). In contrast, yeasts and amoebozoa have lost **centrioles** and possess **acentriolar** centrosomes—called the spindle pole body (SPB) and the nucleus-associated body (NAB), respectively. Despite the difference in their structures, centriolar centrosomes and SPBs not only share components but also common biogenesis regulators.
Acentriolar centrosomes should continue to be a great model to understand how centrosomes evolved and how centrosome biogenesis is regulated.
In the field of centrosome biology, the yeast SPB has been described as “equivalent to the centrosome” but its evolution and origin have been less understood and discussed.
the PCM is remarkably conserved in terms of molecular composition and regulation due to its indispensable function to nucleate microtubules at the centrosome.
analyses of the centrosome structure, components and functions from a greater variety of species give us more hints in order to reconstitute the evolutionary history of the centrosome and understand how the ancestral centrosome was remodelled and diverse structures arose. Better understanding the centrosome evolution will lead to discovering the essential and fundamental mechanism to assemble the functional organelle. The diverged centrosomes should continue to be a great model to understand how the centrosomes evolved and biogenesis is regulated.