Biological complexity: control of cell skeletal structure (Introduction)

by David Turell , Thursday, February 20, 2020, 23:23 (1527 days ago) @ David Turell

One of the jobs of centrosomes and its parts, centrioles:

https://phys.org/news/2020-02-scaffold-center-cellular-skeleton.html

"All animal cells have an organelle called a centrosome, which is essential to the organization of their cell skeleton. The centrosome plays fundamental roles, especially during cell division, where it allows equal sharing of genetic information between two daughter cells. When the cells stop dividing, the centrioles, cylindrical structures composed of microtubules at the base of the centrosome, migrate to the plasma membrane and allow the formation of primary and mobile cilia, which are used respectively for the transfer of information and the genesis of movement. While performing these crucial biological functions, centrioles are therefore subjected to many physical forces, which they must resist. Scientists from the University of Geneva (UNIGE) have discovered an internal structure at the center of these nano-cylinders, a real cellular scaffolding that maintains the physical integrity of this organelle. This study, published in the journal Science Advances, will provide a better understanding of the functions of the centriole and the pathologies associated with its dysfunction. (my bold)

" The centrioles, cylindrical nano-structures, form the centrosome, the main microtubule organizing center of the cell skeleton, and the cilia, real cellular antennas. Defects in the assembly or functioning of the centriole can lead to pathologies in humans, such as ciliopathies—retinal disorders that can cause loss of vision.

"Centrioles, formed by microtubules, are components of the cell skeleton. "They have a canonical organization defined by nine triplets of microtubules that must be maintained as a structural unit in order to resist the various forces they face during their cellular functions," explains Paul Guichard, Professor in the Department of Cell Biology of the Faculty of Science at UNIGE.

"The group of Paul Guichard and Virginie Hamel, a researcher at the Department of Cell Biology and co-leader of the study, discovered an internal scaffolding for this organelle using high-powered electron microscopes, ..."This study allowed to analyze centrioles of four different species and to demonstrate that this inner scaffold is present systematically," reports Maeva Le Guennec, a UNIGE researcher.

"We then investigated which centriolar proteins were located in this new structure," says Virginie Hamel. To do this, the UNIGE researchers used an innovative super-resolution method, called expansion microscopy, which makes it possible to inflate cells without deforming them in order to observe their internal organization. Thus, they were able to identify four proteins that are located at the level of this inner scaffold."

Comment: Cells are highly complex protein structures with builtin processes to maintain proper shape and function. By the way, the centrosome and centrioles are part of the Albrecht-Buehler discussion about cell intelligence. A=B does not agree with most researchers theories:

"Yet, the vast majority of today's biologists devote their efforts to prove the opposite, namely that specific molecular interactions create the cellular functions"

http://www.basic.northwestern.edu/g-buehler/FRAME.HTM

This study discussion is structure, but the controls must originate in the genome instructions. Note the bold in first paragraph above. I wonder what A-B thinks now since his research dates from 25-50 years ago.