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bioRxiv · 10.1101/450916

Organ-wide and ploidy-dependent regulations both contribute to cell size determination: evidence from a computational model of tomato fruit

Baldazzi, V.·Valsesia, P.·Genard, M.·Bertin, N.
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Abstract

The development of a new organ is the result of coordinated events of cell division and expansion, in strong interaction with each other. This paper presents a dynamic model of tomato fruit development that includes cells division, endoreduplication and expansion processes. The model is used to investigate the interaction among these developmental processes, in the perspective of a neo-cellular theory. In particular, different control schemes (either cell-autonomous or organ-controlled) are tested and results compared to observed data from two contrasted genotypes. The model shows that a pure cell-autonomous control fails to reproduce the observed cell size distribution, and an organ-wide control is required in order to get realistic cell sizes. The model also supports the role of endoreduplication as an important determinant of the final cell size and suggests a possible interaction through carbon allocation and metabolism.

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Baldazzi, V., Valsesia, P., Genard, M., Bertin, N.. 2018-10-24. Organ-wide and ploidy-dependent regulations both contribute to cell size determination: evidence from a computational model of tomato fruit. https://doi.org/10.1101/450916

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