Surf's up for ER stress.

Area of Science:

• Cellular Biology
• Molecular Biology
• Chronobiology

Background:

• The unfolded protein response (UPR) is a critical cellular pathway that mitigates stress caused by misfolded proteins in the endoplasmic reticulum.
• Dysregulation of the UPR is implicated in various diseases, including metabolic disorders, neurodegenerative diseases, and cancer.
• The temporal dynamics of the UPR have not been fully understood, suggesting a potential role for internal cellular timing mechanisms.

Purpose of the Study:

• To investigate the existence and function of a biological clock regulating the unfolded protein response.
• To elucidate the molecular components and mechanisms underlying this novel clock.
• To determine the impact of this clock on cellular homeostasis and disease pathogenesis.

Main Methods:

• Utilized CRISPR-Cas9 screening in mammalian cell lines to identify novel regulators of the UPR.
• Performed time-course experiments measuring UPR markers and clock gene expression.
• Employed biochemical assays and genetic manipulation to validate the interaction between clock components and UPR signaling pathways.

Main Results:

• Identified a novel set of clock genes that directly regulate key effectors of the unfolded protein response.
• Demonstrated that this biological clock imposes a rhythmic pattern on UPR activation and resolution.
• Showcased that disruption of this clock leads to aberrant UPR signaling and increased cellular susceptibility to stress.

Conclusions:

• A previously unrecognized biological clock mechanism governs the unfolded protein response.
• This clock plays a crucial role in maintaining cellular homeostasis by temporally coordinating the UPR.
• Targeting this clock presents a potential therapeutic strategy for diseases associated with UPR dysfunction.