Descrizione del progetto
Svelare il ruolo dello stress nell’evoluzione della poliploidia
Nonostante l’esistenza di diverse specie poliploidi, le duplicazioni dell’intero genoma non sono evidenti nel loro genoma. Si è quindi giunti alla conclusione che le duplicazioni dell’intero genoma abbiano contribuito alla comparsa di specie poliploidi, ma che si siano verificate in periodi specifici durante l’evoluzione, in presenza di condizioni stressanti o di cambiamenti ambientali. Il progetto DOUBLE-TROUBLE, finanziato dall’UE, intende scoprire perché l’ambiente condiziona la poliploidia e sta ipotizzando che le specie poliploidi possiedano un vantaggio in termini di sopravvivenza o forma fisica rispetto alle specie non poliploidi. Alcuni scienziati si occuperanno di eseguire esperimenti rivoluzionari che, abbinati alla modellizzazione, codificheranno le potenzialità adattative dei poliploidi in condizioni di stress o durante periodi caratterizzati da cambiamenti climatici.
Obiettivo
Thousands of species are polyploid. However, the long-term establishment of organisms that have undergone ancient whole genome duplications (WGDs) has been exceedingly rare and when we analyse the genomes of plants and animals, we can, at most, find evidence for a very limited number of WGDs that survived on the longer term. The paucity of (established) ancient genome duplications and the existence of so many species that are currently polyploid provides a fascinating paradox. There is growing evidence that the majority of ancient WGDs were established at specific times in evolution, for instance during periods of environmental change and periods of mass-extinction. The reason for this ‘stress’-polyploidy relationship has been the subject of considerable speculation and several hypotheses have been put forward to explain this observation: (a) stressful conditions promote polyploid formation; (b) polyploidisation causes a niche shift allowing polyploids to grow in conditions that are unsuitable for their non-polyploid ancestors; and (c) polyploids have an increased evolvability and consequently adapt faster to a changing environment. Here, we want to unravel the mechanistic underpinnings of why and how polyploids can outcompete non-polyploids. We will address these questions by replaying the ‘genome duplication tape of life’ in two different model systems, namely Chlamydomonas and Spirodela. We will run long-term evolutionary (and resequencing) experiments. We will complement these experiments with in-silico experiments based on so-called digital organisms running on artificial genomes. Complementary modelling approaches will also be employed to study the effects of polyploidy from an eco-evolutionary dynamics perspective. By integrating the results obtained from these in vivo and in silico experiments, we will obtain important novel insights in the adaptive potential of polyploids under stressful conditions or during times of environmental and/or climate change.
Campo scientifico
Parole chiave
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-ADG - Advanced GrantIstituzione ospitante
9052 ZWIJNAARDE - GENT
Belgio