Descripción del proyecto
Estudio de la regulación genética en plantas
La regulación de la expresión génica en eucariotas es fundamental para la supervivencia, la diferenciación y el desarrollo celular. La regulación en la etapa de síntesis de proteínas es crucial e implica la diana de rapamicina (TOR), una proteína cinasa que inhibe la función de las proteínas represoras de la traducción. Para lograrlo, la ruta de señalización TOR integra la información sobre la disponibilidad de nutrientes y energía, así como la concentración de hormonas y factores de crecimiento. El proyecto TOR in acTIon, financiado con fondos europeo, se propone comprender cómo emplean las plantas la TOR para regular la síntesis de proteínas. El objetivo principal es identificar los factores de regulación que funcionan bajo el control de la TOR en el inicio de la traducción y descifrar la función de la fitohormona auxina, un coordinador fundamental del crecimiento vegetal.
Objetivo
Translation is a critical step in the regulation of gene expression in eukaryotes. Most of the control occurs at the level of translation initiation, which is a rate-limiting step in protein synthesis. In mammals, cap-dependent translation initiation is under the regulation of the target of rapamycin (TOR) protein kinase, which suppresses the function of translation repressor proteins, the eIF4E-binding proteins (4E-BPs) that sequester the cap-binding factor eIF4E at the 5′-end of mRNA. The TOR signaling pathway integrates nutrient and energy sufficiency, hormones and growth factors to regulate protein synthesis in mammals and plants. How TOR signals environmental changes to regulate mRNA translation and ribosome production in plants is at present unknown. This project aims to define the role of the plant TOR kinase in translation regulation and to understand how plants have rewired the TOR signalling pathway for their specific translational programs. We have discovered putative plant translation repressor (TR) proteins that harbour eIF4E binding sites and TOR phosphorylation sites, and will study translation initiation mechanisms and their control by TOR in the shoot apical meristem—a specialized tissue containing a stem cell niche responsible for building the shoot. The main objective of proposed research is to uncover regulatory factors that function under the control of TOR in translation initiation and to identify their targets among meristematic mRNAs. A search for cellular mRNAs whose initiation is regulated by TOR and/or TR proteins will be performed using a global ribosomal profiling approach. The plant hormone auxin is an upstream effector of TOR and impacts stem cell niche activity. Thus, we shall study whether TOR mediates signaling from auxin to control TR activity and translation initiation. Finally, we will test whether TOR couples amino acid sensing to regulation of translation initiation.
Ámbito científico
Programa(s)
Régimen de financiación
MSCA-IF-EF-ST - Standard EFCoordinador
75794 Paris
Francia