Descrizione del progetto
Coordinare la sintesi e il ripiegamento proteico nei metazoi
Per funzionare, le proteine si piegano in forme 3D complesse. Poiché le proteine spesso iniziano a piegarsi durante la traduzione dell’acido ribonucleico messaggero (mRNA), la scelta del codone e la fornitura di acido ribonucleico transfer (tRNA) possono favorire questo processo modulando la velocità di traduzione. Gli scienziati non sanno come i metazoi sfruttino questo meccanismo per garantire l’omeostasi delle proteine. Il progetto TransTempoFold, finanziato dall’UE, stabilirà in che modo i pool di tRNA e le reti regolatrici per la biogenesi delle proteine e l’omeostasi sono adattati ai proteomi specializzati in diversi tipi cellulari. Esso si concentrerà su cellule staminali e linee di progenie differenziate e svilupperà un metodo per modulare i pool di tRNA cellulare in vivo. Il progetto definirà in che modo vengono stabiliti e mantenuti i diversi proteomi cellulari dei metazoi e rivelerà i motivi per cui alcune cellule tollerano meglio le proteine mal ripiegate rispetto ad altre.
Obiettivo
Proteins function only after folding into complex three-dimensional shapes. Loss of protein conformation is detrimental for cellular health, and a hallmark of aging and diverse human diseases. To ensure proteome integrity, cells rely on an intricate interplay between protein synthesis, folding, and quality control. Since proteins often begin to fold during mRNA translation, codon choice and tRNA supply can promote this process by modulating translation speed. How metazoans exploit this mechanism to ensure protein homeostasis over a wide range of cells and tissues, or why some cell types are more vulnerable to translation defects and proteome damage remains unknown. Here, I will define how tRNA pools and the regulatory networks for protein biogenesis and homeostasis are tailored to specialized proteomes in different cell types. I propose a multiscale systems approach centred around: i) stem cells and differentiated progeny lines as a powerful model system, and ii) a novel method to modulate cellular tRNA pools in vivo. Isogenic lines of a range of normal cellular states will be created through the differentiation of human pluripotent stem cells into neuronal and cardiac lineages. In these lineages, I will first quantitate tRNA expression and abundance, and dissect their impact on translation dynamics with ribosome profiling. Second, I will use systematic depletion of individual tRNAs to explore how different cell types respond to imbalanced tRNA pools, and define how mRNA sequence and protein structure patterns program protein folding. Third, I will use loss-of-function screens to uncover evolutionarily conserved regulators of proteome integrity as a function of cell identity. This project will define how diverse metazoan cell proteomes are established and maintained, and reveal why some cells tolerate misfolded proteins better than others.
Campo scientifico
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-STG - Starting GrantIstituzione ospitante
80539 Munchen
Germania