Comprendre la structure du Complexe Synaptonémal chez Arabidopsis thaliana

Understand the structure of the Synaptonemal Complex in Arabidopsis thaliana

• Auteur / Autrice : Youngkyoung Lee
• Direction : Mathilde Grelon
• Type : Projet de thèse
• Discipline(s) : Biologie
• Date : Inscription en doctorat le 28/02/2025
• Etablissement(s) : université Paris-Saclay
• Ecole(s) doctorale(s) : École doctorale Sciences du Végétal : du gène à l'écosystème
• Partenaire(s) de recherche : Laboratoire : IJPB - Institut Jean-Pierre Bourgin-Sciences du Végétal
• Partenaire(s) de recherche : Equipe de recherche : Pôle Génomes
• Partenaire(s) de recherche : Référent : Faculté des sciences d'Orsay

Mots clés

Mots clés libres

Chromosomes

Arabidopsis thaliana

Recombinaison

Méiose

Arabidopsis thaliana

Chromosomes

Meiosis

Recombination

Résumé

Meiosis is a specialized cell division crucial for producing haploid gametes in sexually reproducing organisms. Proper chromosome segregation during meiosis relies on the formation of crossovers (COs) between homologous chromosomes. The progressive designation and maturation of CO precursors occur within a proteinaceous structure known as the synaptonemal complex (SC). While the SC's global structure is conserved, its composition varies among eukaryotes. In Arabidopsis thaliana, the study of the SC is ongoing, and key components, including ZYP1, SCEP1, and SCEP2, have been identified. The project has three main objectives: firstly, to characterize the spatial organization of the SC proteins in A. thaliana; secondly, to study the dynamics of SC polymerization; and thirdly, to identify additional components of the plant SC. Using advanced cytology techniques, the spatial organization of SCEP1, SCEP2, and ZYP1 will be investigated, with a specific focus on their relationships and interactions with other meiotic chromosome components. Live imaging with a SCEP1::GFP fusion will be employed to examine synapsis establishment and progression in living anthers of either wild-type plants or mutants affected in SC formation. To gain a better understanding of the SC composition, a comprehensive analysis of the interaction network between SC proteins and other meiotic proteins will be conducted using Alphafold2 and yeast two-hybrid experiments. Additionally, the forward genetic screen that initially isolated SCEP1 and SCEP2 will be continued. This project combines genetics, cutting edge microscopy techniques, and interaction network analysis to deepen our understanding of the spatial organization, dynamics, and composition of the SC in A. thaliana.