The Benefits of Cotranslational Assembly: A Structural Perspective

The faithful assembly of protein complexes in space and time is a hallmark of cellular homeostasis. Complex assembly might be seeded already during translation, if interacting subunits are recruited to the nascent chain. Here, we review recent discoveries suggesting that such cotranslational assembly is a prominent feature throughout the proteome. It might contribute to the efficiency and efficacy of assembly and occurs in coordination rather than competition with chaperones. We discuss how cotranslational assembly structurally contributes to the organizational order of assembly pathways and their surveillance. Taken together, these novel insights suggest that cotranslational assembly is intimately linked with the regulation of protein abundance, stability, and activity, offering an attractive explanation for many cellular phenomena.