How the cell’s “antenna” works better understood

The essential role of a protein in the functioning of the cell is better defined following work carried out in the laboratory of Dr. Frédéric Charron, at the Montreal Clinical Research Institute (IRCM), and at the University of California at Merced, United States.

This breakthrough allows us to better understand cellular defects that lead to the development of small cerebellums, which can cause global developmental delay, motor sequelae, intellectual deficit and language disorders.

Like a cell antenna

The human body has thousands of cell types, most of which have similar basic structures, such as the nucleus, which contains theDNA.

One such structure found in most cells is the primary cilium. recent years that it played an essential role in cell signaling”,”text”:”The cilium has long been considered a vestige of evolution [une structure anatomique qui a perdu ses fonctions originelles au cours de l’évolution]but we have realized in the last 20 years that it plays an essential role in cell signaling”}}”>The eyelash has long been considered a vestige of evolution. [une structure anatomique qui a perdu ses fonctions originelles au cours de l’évolution]but it has been realized in the last 20 years that it plays an essential role in cell signalingexplains Dr Frédéric Charron, from theIRCM.

The primary cilium is a protuberance of the cell that resembles an antenna. It also acts a bit like an antenna since it is used to detect signals present in the cell’s environment, some of which are responsible for stimulating cell proliferation.indicates Dr. Charron.

Our work shows that a protein called NUMB is essential for transmitting signals detected by the antenna.

When the antenna detects a signal, it must be transmitted to the cell to have an effect. What we found is the way in which the primary cilium is able to transmit certain signals thanks to NUMB, adds the researcher.

When the line is bad

Without this protein, the signal is detected by the cilium, but its information is not transmitted to the rest of the cell, which prevents it from having the usual effect. The problem [ne concerne pas] reception, but good […] signal transmission, specifies Dr Charron.

In the present work, the team from Dr. Charron’s laboratory was interested in a signal in particular, that of a protein which induces cell proliferation.

The proliferation signal is what makes a cell multiply. It will trigger the cell cycle, which allows the cell to replicate its DNA to then divide into two daughter cells which will in turn divide.

This process leads to cell multiplication, and NUMB plays an essential role.

However, without the transmission of the signal due to the absence of NUMB, the proliferation of certain brain cells does not occur.

In experiments carried out on mice, when we inactivate the gene which codes for the NUMB protein, we witness a very strong reduction in the capacity of the cells [des neurones] to multiply.

These are defects that impair the development of the brain and nervous system by leading to the formation of small cerebellums, a condition called cerebellar hypoplasiaindicates the scientist.

Researchers will try to better understand the role of NUMB in future work.

Unfortunately, for the moment, we do not know of molecules or drugs that could correct the absence of the protein.

What we would like to understand better is the impact of the mechanism that we have discovered on other diseases of brain development in order to possibly succeed in creating new therapies, notes Dr Charron.

The two main authors of this work published in the journal Nature Communications (New window) (in English) are Drs Patricia Yam, from theIRCM, and Xuecai Ge, from the University of California, Merced, USA.