L'homéostasie est régulée par la dégradation dépendante de l'ubiquitine et la séquestration dans des condensats cytoplasmiques

Des chercheurs du LRSV ont publié en mai dans IScience un article dont les données suggèrent que le partitionnement nucléocytoplasmique, la condensation et la dégradation dépendante de l'ubiquitine régulent les niveaux de LFY dans le noyau pour contrôler son activité.

The transcription factor LFY is crucial for flower development by activating floral genes. It accumulates in cytoplasmic condensates, where UFO interacts with it for degradation. Perturbing these condensates relocates LFY to the nucleus, activating floral genes, revealing regulation of LFY activity.

"In details, the transcription factor LEAFY (LFY) plays crucial roles in flower development by activating floral homeotic genes. Activation of LFY targets requires the combined action of LFY and the E3 ubiquitin ligase UFO, although the precise underlying mechanism remains unclear. Here, we show that LFY accumulates in biomolecular condensates within the cytoplasm, while recombinant LFY forms condensates with similar properties in vitro. UFO interacts with LFY within these condensates and marks it for degradation. LFY levels in the nucleus are buffered against changes in total LFY levels induced by proteasome inhibition, UFO overexpression, or mutation of lysine residues in a disordered region of LFY. Perturbation of cytoplasmic LFY condensates by 1,6-hexanediol treatment induces the relocalization of LFY to the nucleus and the subsequent activation of the LFY target AP3 in flowers. Our data suggest that nucleocytoplasmic partitioning, condensation, and ubiquitin-dependent degradation regulate LFY levels in the nucleus to control its activity."

Voir aussi

Dolde, U., Muzzopappa, F., Delesalle, C., Neveu, J., Erdel, F., and Vert, G
iScience. 2023 May 15;26(6):106880. https://pubmed.ncbi.nlm.nih.gov/37260753/
Homeostasis is regulated via ubiquitin-dependent degradation and sequestration in cytoplasmic condensates

Contact : Julie NEVEU julie.neveu1@univ-tlse3.fr