Observing the dinosaur specimen skeleton, you may be fascinated by the beautiful repeating structure of the spine.
Where does this exact regularity come from?While the developmental processes that form the body of an animal are very precisely controlled, each cell is full of fluctuations (noise).Nevertheless, it was a big mystery for biology how the body was made accurately, says a research group of Associate Professor Naoki Honda and Associate Professor Takateru Matsui of Nara Institute of Science and Technology.
This time, the research group focused on the formation of repeating structures called somites, which are the basis of the spine.In previous studies, genes that are activated at regular time intervals play the role of "body clock", and a molecule called ERK is inactivated in accordance with this rhythm to create uniform somites. It was known that if the clock did not work, the segment would be uneven, but the mechanism by which the clock guarantees the reproducibility of the segment was unknown.
In this study, we investigated the effects of noise and the behavior of ERK activity using a mathematical model that simulates somitogenesis with a computer.As a result, in the absence of a clock, the effects of noise propagate through cell-to-cell communication, resulting in loss of cell-wide coordination and ERK inactivation at irregular timings, while the clock ticks. It was found that the noise propagation was shut out to enhance the coordination of the cells, and that the inactivation of ERK occurred accurately at regular intervals.Furthermore, we succeeded in demonstrating the validity of this mathematical model using zebrafish embryos.
This achievement, which revealed that the rhythm of the clock has the effect of canceling noise and controls the formation of somitogenesis by coordinating cells like a conductor, is the prevention of developmental diseases in humans (such as spinal rib abnormalities). And may lead to treatment.
Paper information:[PLoS Computational Biology] Noise-resistant developmental reproducibility in vertebrate somite formation
