3. De Pénélope tissant sa toile à l’enzyme qui efface le temps

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Cette 3ème chronique démarre avec un récit de la mythologie grecque présent dans le poème « L’Odyssée » écrit par le poète Homère. Ce récit nous raconte comment la fidèle Pénélope parvient à repousser ses prétendants en attendant durant 20 ans le retour de son mari Ulysse. Elle a promis à ses soupirants de choisir l’un d’entre eux le jour où elle finira de tisser le linceul destiné au père d’Ulysse. Mais elle va défaire chaque nuit la toile qu’elle tisse le jour, parvenant par ce subterfuge à suspendre le temps. Puis cette chronique se poursuit par une étonnante histoire scientifique qui va nous conduire à la découverte d’une enzyme appelée la télomérase. Cette enzyme reconstruit dans certaines de nos cellules les parties terminales de nos chromosomes appelées les télomères, et que les générations cellulaires successives tendent normalement à raccourcir. Et nous verrons que la télomérase, comme Pénélope, permet de suspendre le temps.

Auteur : Yves Muller – Professeur Agrégé de classe exceptionnelle - Docteur en Neurosciences - Université de Montpellier

3. Biological Chronicles - From Penelope weaving her shroud to the enzyme that erases time

Our chronicle begins with an account of Greek mythology from "The Odyssey" written by the poet Homer. This story tells us how the faithful Penelope manages to hold off her suitors for twenty years while awaiting the return of her husband Ulysses. She promises her suitors that she will make her choice the day she finishes weaving the shroud for Ulysses' father. But each night she undoes the canvas woven during the day, thus managing to suspend time. Our chronicle continues with an astonishing scientific story which leads us to the discovery of an enzyme called telomerase. In certain cells, this enzyme rebuilds the terminal parts of our chromosomes called telomeres, which successive cell generations normally tend to shorten. And we will see that telomerase, like Penelope, makes it possible to suspend time.

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