How embryos scale vertebrae
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Neighbouring cells in the future vertebrae column of an embryo coordinate to turn specific genes on and off in turn, generating a wave of gene expression similar to the 鈥楽lide to unlock鈥 animation on a smart phone. To study this process, and determine its impact on how proportions of the future vertebrae are maintained, the researchers developed a new technique.
鈥淯sing this new assay, we were able to film this wave of gene expression in real time with high precision, and to identify whether this pattern could change according to the overall size,鈥 explains Alexander Aulehla who coordinated the study at EMBL Heidelberg. 鈥淭here is a clear link: when the embryo is smaller, the number of segments formed remains the same, but each segment is smaller and the expression waves are proportionally slower.鈥
The speed of the wave seems to be the essential characteristic to predict the size of the future vertebra: the faster the wave, the bigger the vertebrae. Similar expression waves have been observed in several vertebrates and also in insect species, so this communication pattern among embryonic cells seems to be widespread. However, scientists haven鈥檛 yet elucidated how the speed of the wave is controlled at a molecular level.
Paul Fran莽ois, an assistant professor of Physics at 成人VR视频, collaborated with the EMBL research team by writing a computer model of what happens in the tissue.听 鈥淲hat surprised me is that you can reproduce the complex behavior with a relatively simple, three-parameter mathematical model. This suggests mechanisms that maybe tested in the future to understand how embryonic cells coordinate with each other to ensure formation of properly sized vertebrae.鈥
Francois鈥檚 research focuses on the modeling of physical properties of gene networks and their evolution 鈥 a field that has emerged at the nexus of biology and physics in recent years, following sequencing of the human genome and rapid growth in scientists鈥 understanding of the processes inside cells.
To view the film of gene expression in an embryo: