2025/07/24 by Xiuqi Chen, Vincent J. Hilser, Christian Kaiser · 1 voice
Biochemistry, Genetics and Molecular Biology · #RNA and protein synthesis mechanisms #Protein Structure and Dynamics #Bacterial Genetics and Biotechnology
paper · pdf · doi:10.1038/s41467-025-61398-6
openalex publication_date 2025/07/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
Cytosolic proteins begin to fold co-translationally as soon as they emerge from the ribosome during translation. These early co-translational steps are crucial for overall folding and are guided by an intricate network of interactions with molecular chaperones. Because cellular co-translational folding is challenging to detect, its timing and progression remain largely elusive. To quantitatively define co-translational folding in live cells, we developed a high-throughput method that we term “Arrest Peptide Profiling” (AP Profiling). Combining AP Profiling with single-molecule experiments, we delineate co-translational folding for a set of GTPase domains with similar structures, defining how topology shapes folding pathways. Genetic ablation of nascent chain-binding chaperones results in discrete and localized folding changes, highlighting how functional redundancy among chaperones is achieved by distinct engagement with the nascent protein. Our work provides a window into cellular folding pathways of structurally intricate proteins and paves the way for systematic studies of nascent protein folding at exceptional resolution and throughput. Protein folding is facilitated by cellular machinery, but studying folding in the cellular context is challenging. Here, the authors developed Arrest Peptide Profiling to map co-translational folding and chaperone interactions in living cells.