A proposed mechanism for the interaction of the segmentation clock and the determination front in somitogenesis.
BACKGROUND
Recent discoveries in the field of somitogenesis have confirmed, for the most part, the feasibility of the clock and wavefront model. There are good candidates for both the clock (various genes expressed cyclically in the tail bud of vertebrate embryos have been discovered) and the wavefront (there are at least three different substances, whose expression levels vary along the presomitic mesoderm [PSM], that have important effects on the formation of somites). Nevertheless, the mechanisms through which the wavefront interacts with the clock to arrest the oscillations and induce somite formation have not yet been fully elucidated.


RESULTS
In this work, we propose a gene regulatory network which is consistent with all known experimental facts in embryonic mice, and whose dynamic behaviour provides a potential explanation for the periodic aggregation of PSM cells into blocks: the first step leading to the formation of somites.


CONCLUSIONS
To our knowledge, this is the first proposed mechanism that fully explains how a block of PSM cells can stop oscillating simultaneously, and how this process is repeated periodically, via the interaction of the segmentation clock and the determination front.
Santillán
Moisés
M
Campus Monterrey, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (IPN), Apodaca, Nuevo León, México.
Mackey
Michael C
MC
D000818:Animals; D001683:Biological Clocks / Q000235:genetics*; D004622:Embryo, Mammalian; D047108:Embryonic Development; D004627:Embryonic Induction; D053263:Gene Regulatory Networks; D051379:Mice; D038081:Organogenesis; D019170:Somites / Q000196:embryology*