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arXiv · 0704.3071

Converting genetic network oscillations into somite spatial pattern

K. I. Mazzitello·C. M. Arizmendi·H. G. E. Hentschel
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Abstract

In most vertebrate species, the body axis is generated by the formation of repeated transient structures called somites. This spatial periodicity in somitogenesis has been related to the temporally sustained oscillations in certain mRNAs and their associated gene products in the cells forming the presomatic mesoderm. The mechanism underlying these oscillations have been identified as due to the delays involved in the synthesis of mRNA and translation into protein molecules [J. Lewis, Current Biol. {\bf 13}, 1398 (2003)]. In addition, in the zebrafish embryo intercellular Notch signalling couples these oscillators and a longitudinal positional information signal in the form of an Fgf8 gradient exists that could be used to transform these coupled temporal oscillations into the observed spatial periodicity of somites. Here we consider a simple model based on this known biology and study its consequences for somitogenesis. Comparison is made with the known properties of somite formation in the zebrafish embryo . We also study the effects of localized Fgf8 perturbations on somite patterning.

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K. I. Mazzitello, C. M. Arizmendi, H. G. E. Hentschel. 2007-04-23. Converting genetic network oscillations into somite spatial pattern. https://doi.org/10.1103/physreve.78.021906

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