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publications

Impact of cycling cells and cell cycle regulation on Hydra regeneration.

Hydra tissues are made from three distinct populations of stem cells that continuously cycle and pause in G2 instead of G1. To characterize the role of cell proliferation after mid-gastric bisection, we have (i) used flow cytometry and classical markers to monitor cell cycle modulations, (ii) quantified the transcriptomic regulations of 202 genes associated with cell proliferation during head and foot regeneration, and (iii) compared the impact of anti-proliferative treatments on regeneration efficiency. We confirm two previously reported events: an early mitotic wave in head-regenerating tips, when few cell cycle genes are up-regulated, and an early-late wave of proliferation on the second day, preceded by the up-regulation of 17 cell cycle genes. These regulations appear more intense after mid-gastric bisection than after decapitation, suggesting a position-dependent regulation of cell proliferation during head regeneration. Hydroxyurea, which blocks S-phase progression, delays head regeneration when applied before but not after bisection. This result is consistent with the fact that the Hydra central region is enriched in G2-paused adult stem cells, poised to divide upon injury, thus forming a necessary constitutive pro-blastema. However a prolonged exposure to hydroxyurea does not block regeneration as cells can differentiate apical structures without traversing S-phase, and also escape in few days the hydroxyurea-induced S-phase blockade. Thus Hydra head regeneration, which is a fast event, is highly plastic, relying on large stocks of adult stem cells paused in G2 at amputation time, which immediately divide to proliferate and/or differentiate apical structures even when S-phase is blocked.

news

Nature « Nouvelles & Opinions» : la recherche en 2017

Un article sur des résultats issus de l’UNIGE est sélectionné par les éditeurs du prestigieux journal Nature comme l’un des 7 « Nouvelles et opinions » de l’année

événements

to be announced

24.01.2018 11:15, 1S059 (Sciences III)

Antony Dodd (University of Bristol).
organisé par: Theresa Fitzpatrick.

Recherche

Notre département regroupe 12 laboratoires de recherche employant un total de presque 200 scientifiques, ingénieurs et techniciens. Les sujets de recherche de ces laboratoires vont de la génétique du développement à la régénération en passant par l'evo-devo, la biologie physique, phylogénétique, la systématique et l'anthropologie.

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Education

Nos professeurs et enseignants participe directement à l'enseignement des sciences de la vie à l'Université de Genève. Nous proposons aussi des spécialisations aux étudiants en master et aux doctorants à travers divers programmes.

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Département de Génétique et Evolution
4, Boulevard d'Yvoy
1205 Genève
Suisse

bureau: 4002A
T: +41 22 379 67 85

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