Proteolytic Mechanisms in Cellular Protein Regulation

In eukaryotic and prokaryotic cells alike, controlled protein degradation underpins a vast array of physiological processes, ranging from quality control to signal transduction. Central to this is proteostasis, the coordinated action of proteolytic systems that maintain protein folding, dismantle damaged polypeptides and regulate levels of key factors. The ubiquitin–proteasome system orchestrates targeted turnover of short-lived and regulatory proteins, whereas autophagy channels larger assemblies and organelles to lysosomal compartments for breakdown. Parallel pathways employ specialised proteases—such as AAA+ unfoldases and mitochondrial matrix proteases—to remodel or degrade substrates in a highly regulated fashion. Proteolytic activation of zymogens, notably by caspases, modulates programmed cell death and inflammation, while signal peptide peptidases and endopeptidases fine-tune protein sorting and receptor signalling. Crosstalk among these pathways allows cells to adapt dynamically to stress, adjust metabolic flux and govern the cell cycle. Dysregulation of proteolytic networks is implicated in a spectrum of diseases, including neurodegeneration, cancer and infection, driving efforts to exploit proteolytic targets for therapeutic intervention.

Research from Nature Portfolio

Recent studies have yielded high-resolution insights into allosteric control and therapeutic targeting of proteases. A novel small molecule, ZK53, was shown to bind selectively to mitochondrial ClpP, exploiting π-π stacking interactions within its hydrophobic pocket to enhance proteolytic activity and disrupt oxidative phosphorylation in lung squamous carcinoma cells, thereby inducing cell-cycle arrest in vivo. Complementary work on acyldepsipeptides and AAA+ chaperone interactions has elucidated how small-molecule activators and protein cofactors allosterically stabilise distinct ClpP conformations, revealing the dynamic interplay between pore opening and catalytic site activation. These findings collectively advance our understanding of ClpP regulation and open avenues for precision modulation of protease function.

Proteolytic Mechanisms in Cellular Protein Regulation publication trend

The graph below shows the total number of articles in proteolytic mechanisms in cellular protein regulation across all publications each year (not limited to Nature Index journals).

Technical terms

Proteostasis: The maintenance of cellular protein balance through coordinated synthesis, folding, trafficking and degradation.

Ubiquitin–proteasome system: A pathway in which target proteins are tagged with ubiquitin chains and degraded by a multi-subunit proteasome complex.

AAA+ proteases: ATP-dependent molecular machines that unfold substrates and translocate them into a proteolytic chamber for degradation.

Autophagy: A lysosome-mediated process that engulfs and degrades large protein aggregates and organelles.

BacPROTACs: Bifunctional molecules designed to recruit bacterial proteases for the targeted degradation of specific proteins.

References

1. Clp-targeting BacPROTACs impair mycobacterial proteostasis and survival. Cell (2023).
2. Selective activator of human ClpP triggers cell cycle arrest to inhibit lung squamous cell carcinoma. Nature Communications (2023).
3. AAA+ chaperones and acyldepsipeptides activate the ClpP protease via conformational control. Nature Communications (2015).
4. Lon protease 1-mediated metabolic reprogramming promotes the progression of prostate cancer. Cell Death & Disease (2025).