Description du projet
Le rôle de l’élimination programmée de l’ADN dans l’évolution et le développement
Chez certains organismes, les génomes des cellules de lignée germinale et des cellules somatiques diffèrent considérablement. L’élimination programmée de l’ADN est considérée comme responsable de cette observation, car elle supprime les gènes et les éléments répétitifs au cours de la différenciation des cellules somatiques. Le projet GermlineChrom, financé par l’UE, se concentrera sur le chromosome restreint à la lignée germinale présent dans la lignée germinale de certaines espèces d’oiseaux, comme le diamant mandarin, et supposé contenir du matériel génétique inutile ou nuisible pour les cellules somatiques. Les chercheurs étudieront et fourniront des informations fondamentales sur le rôle de l’élimination programmée de l’ADN, son évolution et son mécanisme d’héritage chez le diamant mandarin.
Objectif
Many multicellular organisms have a division between germline and soma. It has been long-standing dogma that all these cells have the same genome as they develop from a single cell. However, programmed DNA elimination can remove DNA during germline–soma differentiation and thereby lead to dramatic differences in genome organization between tissues. The evolution and function of programmed DNA elimination remains mysterious due to technological limitations and lack of an evolutionary framework. However, a role of this phenomenon in minimizing germline–soma genetic conflict has been suggested. This conflict arises when developmental gene expression is beneficial for the germline but deleterious for the soma.
The aim of this proposal is to test whether programmed DNA elimination allows germline-specific expression of developmental genes to minimize germline–soma conflict. Using the germline-restricted chromosome (GRC) of the zebra finch as a unique study system, I have recently pioneered high-throughput genomics to overcome previous limitations. Combining my novel approach with transcriptomics, proteomics, cytogenetics, and developmental and functional genomics will provide unprecedented insights into the evolution and function of germline–soma genome differences.
First, I will establish the so far first GRC study system by generating a zebra finch GRC reference assembly. Second, I will test how the GRC is inherited and maintained in zebra finch populations. Third, I will elucidate the long-term evolutionary history of GRCs across songbirds to reveal genes that are most conserved and thus candidates for GRC function. Fourth, I will trace GRC expression and elimination across zebra finch development, and functionally validate candidate genes. Altogether, I will establish an evolutionary framework which will significantly advance our understanding of programmed DNA elimination during germline–soma differentiation, a phenomenon likely widespread across the Tree of Life.
Champ scientifique
Mots‑clés
Programme(s)
Régime de financement
ERC-COG - Consolidator GrantInstitution d’accueil
53113 Bonn
Allemagne